注塑模具电铸镍壳毕业论文中英文对照资料外文翻译文献
塑料注塑模具中英文对照外文翻译文献
外文翻译及原文(文档含英文原文和中文翻译)【原文一】CONCURRENT DESIGN OF PLASTICS INJECTION MOULDS AbstractThe plastic product manufacturing industry has been growing rapidly in recent years. One of the most popular processes for making plastic parts is injection moulding. The design of injection mould is critically important to product quality and efficient product processing.Mould-making companies, who wish to maintain the competitive edge, desire to shorten both design and manufacturing leading times of the by applying a systematic mould design process. The mould industry is an important support industry during the product development process, serving as an important link between the product designer and manufacturer. Product development has changed from the traditional serial process of design, followed by manufacture, to a more organized concurrent process where design and manufacture are considered at a very early stage of design. The concept of concurrent engineering (CE) is no longer new and yet it is still applicable and relevant in today’s manuf acturing environment. Team working spirit, management involvement, total design process and integration of IT tools are still the essence of CE. The application of The CE process to the design of an injection process involves the simultaneous consideration of plastic part design, mould design and injection moulding machine selection, production scheduling and cost as early as possible in the design stage.This paper presents the basic structure of an injection mould design. The basis of this system arises from an analysis of the injection mould design process for mould design companies. This injection mould design system covers both the mould design process and mould knowledge management. Finally the principle of concurrent engineering process is outlined and then its principle is applied to the design of a plastic injection mould.Keywords :Plastic injection mould design, Concurrent engineering, Computer aided engineering, Moulding conditions, Plastic injection moulding, Flow simulation1.IntroductionInjection moulds are always expensive to make, unfortunately without a mould it can not be possible ho have a moulded product. Every mould maker has his/her own approach to design a mould and there are many different ways of designing and building a mould. Surely one of the most critical parameters to be considered in the design stage of the mould is the number of cavities, methods of injection, types of runners, methods of gating, methods of ejection, capacity and features of the injection moulding machines. Mould cost, mould quality and cost of mould product are inseparableIn today’s completive environment, computer aided mould filling simulation packages can accurately predict the fill patterns of any part. This allows for quick simulations of gate placements and helps finding the optimal location. Engineers can perform moulding trials on the computer before the part design is completed. Process engineers can systematically predict a design and process window, and can obtain information about the cumulative effect of the process variables that influence part performance, cost, and appearance.2.Injection MouldingInjection moulding is one of the most effective ways to bring out the best in plastics. It is universally used to make complex, finished parts, often in a single step, economically, precisely and with little waste. Mass production of plastic parts mostly utilizes moulds. The manufacturing process and involving moulds must be designed after passing through the appearance evaluation and the structure optimization of the product design. Designers face a hugenumber of options when they create injection-moulded components. Concurrent engineering requires an engineer to consider the manufacturing process of the designed product in the development phase. A good design of the product is unable to go to the market if its manufacturing process is impossible or too expensive. Integration of process simulation, rapid prototyping and manufacturing can reduce the risk associated with moving from CAD to CAM and further enhance the validity of the product development.3. Importance of Computer Aided Injection Mould DesignThe injection moulding design task can be highly complex. Computer Aided Engineering (CAE) analysis tools provide enormous advantages of enabling design engineers to consider virtually and part, mould and injection parameters without the real use of any manufacturing and time. The possibility of trying alternative designs or concepts on the computer screen gives the engineers the opportunity to eliminate potential problems before beginning the real production. Moreover, in virtual environment, designers can quickly and easily asses the sensitivity of specific moulding parameters on the quality and manufacturability of the final product. All theseCAE tools enable all these analysis to be completed in a meter of days or even hours, rather than weeks or months needed for the real experimental trial and error cycles. As CAE is used in the early design of part, mould and moulding parameters, the cost savings are substantial not only because of best functioning part and time savings but also the shortens the time needed to launch the product to the market.The need to meet set tolerances of plastic part ties in to all aspects of the moulding process, including part size and shape, resin chemical structure, the fillers used, mould cavity layout, gating, mould cooling and the release mechanisms used. Given this complexity, designers often use computer design tools, such as finite element analysis (FEA) and mould filling analysis (MFA), to reduce development time and cost. FEA determines strain, stress and deflection in a part by dividing the structure into small elements where these parameters can be well defined. MFA evaluates gate position and size to optimize resin flow. It also defines placement of weld lines, areas of excessive stress, and how wall and rib thickness affect flow. Other finite element design tools include mould cooling analysis for temperature distribution, and cycle time and shrinkage analysis for dimensional control and prediction of frozen stress and warpage.The CAE analysis of compression moulded parts is shown in Figure 1. The analysis cycle starts with the creation of a CAD model and a finite element mesh of the mould cavity. After the injection conditions are specified, mould filling, fiber orientation, curing and thermal history, shrinkage and warpage can be simulated. The material properties calculated by the simulation can be used to model the structural behaviour of the part. If required, part design, gate location and processing conditions can be modified in the computer until an acceptable part is obtained. After the analysis is finished an optimized part can be produced with reduced weldline (known also knitline), optimized strength, controlled temperatures and curing, minimized shrinkage and warpage.Machining of the moulds was formerly done manually, with a toolmaker checking each cut. This process became more automated with the growth and widespread use of computer numerically controlled or CNC machining centres. Setup time has also been significantly reduced through the use of special software capable of generating cutter paths directly from a CAD data file. Spindle speeds as high as 100,000 rpm provide further advances in high speed machining. Cutting materials have demonstrated phenomenal performance without the use of any cutting/coolant fluid whatsoever. As a result, the process of machining complex cores and cavities has been accelerated. It is good news that the time it takes to generate a mould is constantly being reduced. The bad news, on the other hand, is that even with all these advances, designing and manufacturing of the mould can still take a long time and can be extremely expensive.Figure 1 CAE analysis of injection moulded partsMany company executives now realize how vital it is to deploy new products to market rapidly. New products are the key to corporate prosperity. They drive corporate revenues, market shares, bottom lines and share prices. A company able to launch good quality products with reasonable prices ahead of their competition not only realizes 100% of the market before rival products arrive but also tends to maintain a dominant position for a few years even after competitive products have finally been announced (Smith, 1991). For most products, these two advantages are dramatic. Rapid product development is now a key aspect of competitive success. Figure 2 shows that only 3–7% of the product mix from the average industrial or electronics company is less than 5 years old. For companies in the top quartile, the number increases to 15–25%. For world-class firms, it is 60–80% (Thompson, 1996). The best companies continuously develop new products. AtHewlett-Packard, over 80% of the profits result from products less than 2 years old! (Neel, 1997)Figure 2. Importance of new product (Jacobs, 2000)With the advances in computer technology and artificial intelligence, efforts have been directed to reduce the cost and lead time in the design and manufacture of an injection mould. Injection mould design has been the main area of interest since it is a complex process involving several sub-designs related to various components of the mould, each requiring expert knowledge and experience. Lee et. al. (1997) proposed a systematic methodology and knowledge base for injection mould design in a concurrent engineering environment.4.Concurrent Engineering in Mould DesignConcurrent Engineering (CE) is a systematic approach to integrated product development process. It represents team values of co-operation, trust and sharing in such a manner that decision making is by consensus, involving all per spectives in parallel, from the very beginning of the productlife-cycle (Evans, 1998). Essentially, CE provides a collaborative, co-operative, collective and simultaneous engineering working environment. A concurrent engineering approach is based on five key elements:1. process2. multidisciplinary team3. integrated design model4. facility5. software infrastructureFigure 3 Methodologies in plastic injection mould design, a) Serial engineering b) Concurrent engineeringIn the plastics and mould industry, CE is very important due to the high cost tooling and long lead times. Typically, CE is utilized by manufacturing prototype tooling early in the design phase to analyze and adjust the design. Production tooling is manufactured as the final step. The manufacturing process and involving moulds must be designed after passing through the appearance evaluation and the structure optimization of the product design. CE requires an engineer to consider the manufacturing process of the designed product in the development phase.A good design of the product is unable to go to the market if its manufacturing process is impossible. Integration of process simulation and rapid prototyping and manufacturing can reduce the risk associated with moving from CAD to CAM and further enhance the validity of the product development.For years, designers have been restricted in what they can produce as they generally have todesign for manufacture (DFM) – that is, adjust their design intent to enable the component (or assembly) to be manufactured using a particular process or processes. In addition, if a mould is used to produce an item, there are therefore automatically inherent restrictions to the design imposed at the very beginning. Taking injection moulding as an example, in order to process a component successfully, at a minimum, the following design elements need to be taken into account:1. . geometry;. draft angles,. Non re-entrants shapes,. near constant wall thickness,. complexity,. split line location, and. surface finish,2. material choice;3. rationalisation of components (reducing assemblies);4. cost.In injection moulding, the manufacture of the mould to produce the injection-moulded components is usually the longest part of the product development process. When utilising rapid modelling, the CAD takes the longer time and therefore becomes the bottleneck.The process design and injection moulding of plastics involves rather complicated and time consuming activities including part design, mould design, injection moulding machine selection, production scheduling, tooling and cost estimation. Traditionally all these activities are done by part designers and mould making personnel in a sequential manner after completing injection moulded plastic part design. Obviously these sequential stages could lead to long product development time. However with the implementation of concurrent engineering process in the all parameters effecting product design, mould design, machine selection, production scheduling,tooling and processing cost are considered as early as possible in the design of the plastic part. When used effectively, CAE methods provide enormous cost and time savings for the part design and manufacturing. These tools allow engineers to virtually test how the part will be processed and how it performs during its normal operating life. The material supplier, designer, moulder and manufacturer should apply these tools concurrently early in the design stage of the plastic parts in order to exploit the cost benefit of CAE. CAE makes it possible to replace traditional, sequential decision-making procedures with a concurrent design process, in which all parties can interact and share information, Figure 3. For plastic injection moulding, CAE and related design data provide an integrated environment that facilitates concurrent engineering for the design and manufacture of the part and mould, as well as material selection and simulation of optimal process control parameters.Qualitative expense comparison associated with the part design changes is shown in Figure 4 , showing the fact that when design changes are done at an early stages on the computer screen, the cost associated with is an order of 10.000 times lower than that if the part is in production. These modifications in plastic parts could arise fr om mould modifications, such as gate location, thickness changes, production delays, quality costs, machine setup times, or design change in plastic parts.Figure 4 Cost of design changes during part product development cycle (Rios et.al, 2001)At the early design stage, part designers and moulders have to finalise part design based on their experiences with similar parts. However as the parts become more complex, it gets rather difficult to predict processing and part performance without the use of CAE tools. Thus for even relatively complex parts, the use of CAE tools to prevent the late and expensive design changesand problems that can arise during and after injection. For the successful implementation of concurrent engineering, there must be buy-in from everyone involved.5.Case StudyFigure 5 shows the initial CAD design of plastics part used for the sprinkler irrigation hydrant leg. One of the essential features of the part is that the part has to remain flat after injection; any warping during the injection causes operating problems.Another important feature the plastic part has to have is a high bending stiffness. A number of feeders in different orientation were added to the part as shown in Figure 5b. These feeders should be designed in a way that it has to contribute the weight of the part as minimum aspossible.Before the design of the mould, the flow analysis of the plastic part was carried out with Moldflow software to enable the selection of the best gate location Figure 6a. The figure indicates that the best point for the gate location is the middle feeder at the centre of the part. As the distortion and warpage of the part after injection was vital from the functionality point of view and it has to be kept at a minimum level, the same software was also utilised to yiled the warpage analysis. Figure 5 b shows the results implying the fact that the warpage well after injection remains within the predefined dimensional tolerances.6. ConclusionsIn the plastic injection moulding, the CAD model of the plastic part obtained from commercial 3D programs could be used for the part performance and injection process analyses. With the aid ofCEA technology and the use of concurrent engineering methodology, not only the injection mould can be designed and manufactured in a very short of period of time with a minimised cost but also all potential problems which may arise from part design, mould design and processing parameters could be eliminated at the very beginning of the mould design. These two tools help part designers and mould makers to develop a good product with a better delivery and faster tooling with less time and money.References1. Smith P, Reinertsen D, The time-to-market race, In: Developing Products in Half the Time. New York, Van Nostrand Reinhold, pp. 3–13, 19912.Thompson J, The total product development organization. Proceedings of the SecondAsia–Pacific Rapid Product Development Conference, Brisbane, 19963.Neel R, Don’t stop after the prototype, Seventh International Conference on Rapid Prototyping, San Francisco, 19974.Jacobs PF, “Chapter 3: Rapid Product Development” in Rapid Tooling: Technologies and Industrial Applications , Ed. Peter D. Hilton; Paul F. Jacobs, Marcel Decker, 20005.Lee R-S, Chen, Y-M, and Lee, C-Z, “Development of a concurrent mould design system: a knowledge based approach”, Computer Integrated Manufacturing Systems, 10(4), 287-307, 19976.Evans B., “Simultaneous Engineering”, Mechanical Engi neering , V ol.110, No.2, pp.38-39, 19987.Rios A, Gramann, PJ and Davis B, “Computer Aided Engineering in Compression Molding”, Composites Fabricators Association Annual Conference , Tampa Bay, 2001【译文一】塑料注塑模具并行设计塑料制品制造业近年迅速成长。
塑料模具毕业设计中英文对照资料外文翻译文献
中英文对照资料外文翻译文献一个描述电铸镍壳在注塑模具的应用的技术研究摘要：在过去几年中快速成型技术及快速模具已被广泛开发利用. 在本文中,使用电芯作为核心程序对塑料注射模具分析. 通过差分系统快速成型制造外壳模型. 主要目的是分析电铸镍壳力学特征、研究相关金相组织,硬度,内部压力等不同方面，由这些特征参数以生产电铸设备的外壳. 最后一个核心是检验注塑模具.关键词：电镀；电铸；微观结构；镍1. 引言现代工业遇到很大的挑战，其中最重要的是怎么样提供更好的产品给消费者,更多种类和更新换代问题. 因此,现代工业必定产生更多的竞争性. 毫无疑问,结合时间变量和质量变量并不容易,因为他们经常彼此互为条件; 先进的生产系统将允许该组合以更加有效可行的方式进行，例如,如果是观测注塑系统的转变、我们得出的结论是,事实上一个新产品在市场上具有较好的质量它需要越来越少的时间快速模具制造技术是在这一领域, 中可以改善设计和制造注入部分的技术进步. 快速模具制造技术基本上是一个中小型系列的收集程序，在很短的时间内在可接受的精度水平基础上让我们获得模具的塑料部件。
其应用不仅在更加广阔而且生产也不断增多。
本文包括了很广泛的研究路线,在这些研究路线中我们可以尝试去学习，定义，分析，测试，提出在工业水平方面的可行性，从核心的注塑模具制造获取电铸镍壳，同时作为一个初始模型的原型在一个FDM设备上的快速成型。
不得不说的是,先进的电铸技术应用在无数的行业，但这一研究工作调查到什么程度,并根据这些参数,使用这种技术生产快速模具在技术上是可行的. 都产生一个准确的，系统化使用的方法以及建议的工作方法.2 制造过程的注塑模具薄镍外壳的核心是电铸,获得一个充满epoxic金属树脂的一体化的核心板块模具(图1)允许直接制造注射型多用标本，因为它们确定了新英格兰大学英文国际表卓华组织3167标准。
这样做的目的是确定力学性能的材料收集代表行业。
该阶段取得的核心[4]，根据这一方法研究了这项工作,有如下:a,用CAD系统设计的理想对象b模型制造的快速成型设备(频分多路系统). 所用材料将是一个ABS塑料c一个制造的电铸镍壳，已事先涂有导电涂料(必须有导电).d无外壳模型e核心的生产是背面外壳环氧树脂的抗高温与具有制冷的铜管管道.有两个腔的注塑模具、其中一个是电核心和其他直接加工的移动版. 因此,在同一工艺条件下，同时注入两个标准技术制造，获得相同的工作。
模具设计及制作专业毕业设计外文翻译-中英文对照
IntroductionAlthough the Greek philosopher Democritus had postulated the existence of atoms in the first century BC and Dalton’s atomic theory of 1807 laid the basis for the existence of atoms before the turn of the twentieth century. Indeed, at that time an influential school of German physicists led by Ernst Mach considered the atomic model to be merely a useful picture with no basis in reality.1.1 THE EXISTENCE OF ATOMSThe situation was dramatically changed by an explosion of experimental investigation over the fifteen years between 1897 and 1912. in the 1870s, technical improvements in the construction of vacuum pumps had made possible the investigation of electrical phenomenon in evacuated tubes and the discovery of invisible rays which traveled between an electrically negative electrode (cathode) and an electrically positive electrode (anode) in such a tube.These rays came to be known as cathode rays. At first there was considerable controversy over their nature, but a series of experiments carried out by J.J. Thomson in 1897 demonstrated conclusively that the cathode rays consisted of a stream of negatively charged particles, presumably emitted by atoms in the cathode (Fig. 1.1).Thomson’s measurements of the deflection of the rays by electric and magnetic fields enabled the speed of the particles to be measured and also the ratio of the charge of a particle to its mass. By the turn of the century, the charge-mass radio of these particles, which came to be called electrons, could be measured to quite high precision.However, to give absolute values of the charge and mass, experiments of a different type were required. The most successful were investigations where macroscopic particles such as oil droplets were charged in some way and their motion in electric fields observed. A relatively straightforward measurement of the mass of the oil droplets enabled the charge of the charge of the electron to be measured. The famous experiments carried out by Millikan between 1909 and 1916 gave a value for this charge as 1.592±.002×10-19 coulomb, less than 1 percent lower than that accepted today. This, combined with Thomson’s results, gave a value for the electron’s mass of approximately 9×10-31 kg.Fig. 1.1Schematic diagram of J.J. Thomson’s cathode ray tube Electrons emitted by the cathode are accelerated through the anode. The beam of electrons hits the phosphorescent screen, producing a luminous spot.The measurement of electric charge made possible a direct measurement of atomic masses. Back in 1830, Faraday had carried out experiments on electrolysis. He had used his results to suggest that if matter were atomic, then electricity should also be atomic, but the converse is also true.The flow of electric current between two metallic plates in an electrolyte results in a measurable in increase in the mass of one electrode. The mass of metal deposited per unit charge flowing can be measured. Assuming that the motion of atoms between electrodes in due to the fact that each atom in the electrolyte carries a specified number of excess electrons, the mass of a single atom can be calculated.The investigation of cathode ray tubes produced another important line of experimentation. In 1895 Röntgen had discovered that cathode rays impinging on glass or metal produced a new type of ray –the X-ray. These rays were shown to have wave-like properties and in 1899 their wavelength was estimated by the Dutch physicists Haga and Wind to be of the order of 10-10m, using diffraction at a v-shaped slit. In 1906 Marx demonstrated that the speed of the waves was equal to that of light to within experimental error, and it became generally accepted that X-rays were electromagnetic radiation like light, but with much shorter wavelengths. In 1912 Laue in Germany and Bragg in England demonstrated the diffraction of X-rays by the regular pattern of atoms in a crystal lattice. These diffraction patterns gave the first direct evidence of the existence of atoms and of their sizes. An example is shown in Fig. 1.2.Fig. 1.2Laue diffraction pattern caused by the diffraction of X-rays by the regular lattice of atoms in rock salt.In 1897, Rutherford had found that pieces of the naturally occurring element uranium emitted two types of ray which were termed α rays and βrays. Both could be deflected by electric and magnetic fields and were therefore presumed to consist of charge particles. The βparticles were found to have the same charge and mass as cathode ray electrons, so were assumed to be electrons. The αrays, on the other hand, were considerably more massive. Measurements of their charge and mass suggested that they consisted of helium atoms from which two electrons had been removed. This was confirmed by Rutherford and Royds in 1909, who fired α rays into a sealed and evacuated vessel and showed that helium accumulated in it. The evidence was conclusive that an α particle consisted of a helium atom from which two electrons had been removed.This experiment also confirmed suggestions about the physical meaning of the atomic number Z. This number had been introduced to define the order of elements in the periodic table. Hydrogen had Z=1, helium Z=2and so on. The identification of α particles with helium atoms suggested that Z defined the number of electrons in a particular atom.By 1912, therefore, direct evidence existed on the mass of individual atoms and the size of these atoms. Even more interestingly, the electron appeared to be a constituent of atom, suggesting some internal structure.1.2 THE SIZE OF ATOMSTurning from the historical development of the subject, it is worthwhile to sum up the measurement of atomic masses and dimensions.As mentioned above, direct measurement of atomic masses can be made using electrolysis. A typical electrolysis cell might consist of two copper electrodes immersed in a bath of copper sulphate (Fig. 1.3). A potential difference between the electrodes causes a current to flow an the deposition of copper on the cathode.Fig. 1.3 Electrolytic cell. The anode and cathode are immersed in an electrolyte such as copper sulphate solution. Positively charged copper ions are attracted to the cathode and are deposited there.Several assumptions have to be made. First, it is assumed that in solution the copper sulphate crystals split up, giving free atoms of copper and that these free atoms have an excess positive charge.Second, using chemical knowledge that copper is reasonable extrapolation from the chemical valence theory, if it is assumed that chemical bonds result from the exchange of electrons, and that the lightest atom, hydrogen, has only a single electron to exchange. A copper atom in this state is referred to as being doubly ionized, Cu++. A final assumption is that all copper ions attracted to the cathode stick to it and gain further electrons to become electrically neutral again. The experiment then consists of driving a known quantity of electricity through the cell and measuring the increase in mass of the cathode. Experiments can be carried out with different elements and results confirm the atomic theory and the theory of valence. Most interesting for our discuss is the calculation of the mass of an atom of hydrogen, the lightest element. This turns out to be 1.67×10-27 kg, approximately 1800 times that of an electron.Knowing atomic masses, and the density of materials, it is straightforward to obtain values for atomic dimensions. The only problem is that unless the atoms in a sample of material are arranged in a regular pattern, the answer is not very meaningful. For crystalline substances, X-ray diffraction enable the arrangement of atoms to be discovered. The dimensions of the crystal structure can then be calculated.Fig. 1.4 A single cell of the simple cubic lattice of sodium chloride. The lattice is held together by the attraction between the positively charged sodium ion and the negatively charged chlorine ion.For example, crystals of rock salt (sodium chloride, NaCl) are found to have a cubic structure, with sodium and chlorine ions on alternate corners (Fig. 1.4). If M is the kilogram molecular weight of NaCl and ρ the density of the crystal, the volume of one kg-molecule is/V M ρ=There are 2N atoms is one kg-molecule, where N is Avogadro ’s number. Therefore the distance between the centres of atoms, d is given by:3/(2)d M N ρ=For sodium chloride, this works out as 2.8×10-10m and similar results are obtained for other crystals.Of course, such calculations only tell us the distance between the centres of the atoms and hence the maximum possible size for an atom. To go further, it is necessary to investigate the structure of the atom itself.2.3 THE NUCLEAR MODEL OF THE ATOMFig. 2.2 Classical models of the atom. (a) Thomson’s model. Small, negatively charged electrons are held in a dense, positively charged body.(b) Rutherford’s model. The vast majority of the mass and all the positive charge are concentrated in a relatively tiny nucleus, surrounded by electrons. In both pictures the size of the electrons and of the nucleus are exaggerated. The nucleus should be at least 1000 times smaller and the electrons many times smaller again.In order to explain the result, Rutherford proposed a new model in which all the positive charge and most of the mass of the atom resided in a central nucleus, surrounded by electrons orbiting in free space. The size of the nucleus would be small compared with the size of the atom (Fig.2.2(b)). This model would give a qualitative explanation for Geiger and Marsden’s results as most of the αparticles would pass through the atom without encountering any matter, but a very few would collide with the massive nucleus. However, much more importantly, this model gives a precise quantitative agreement between theory and experiment.Because of the seminal nature of this model, it is worthwhile looking at Rutherford’s analysis in detail. Only classical of physics is required .Fig 2.3Path of αparticle (charge +2e) in the field of the nucleus (charge +Ze). The nucleus is at the origin and is very much more massive than the α particle. The force F is due to electrostatic repulsion.The analysis of the scattering experiment falls into two parts. First, it it necessary to obtain an expression for the deflection of a single αparticle as a function of its kinetic energy and its trajectory relative to the nucleus. The particle and the nucleus are assumed to be very small, and the nucleus is assumed to have a positive charge Ze where e is the electronic charge and Z the atomic number. The α particle has a charge of +2e and the force between it and the nucleus is given by Coulomb’s law. Figure 2.3 shows through situation, with the nucleus situated at the origin. The α particle starts far enough away from the nucleus for the interaction force to be negligible and travels parallel to the χ-axis. An important parameter of the motion is the impact parameter, b, which defines the minimum distance between the nucleus and the particle if the particle were mot deflected.Electrostatic repulsion means that the particle is deflected through an angle Θ and it is obvious that the smaller the value of b, the greater is the value of Θ.It is now possible to work out a value for Θ in terms of b and the kinetic energy of the particle T. Since the mass of the nucleus is much greater than that of the α particle, the kinetic energy and hence the speed of the particle before and after deflection remains the same. However the particle ’s direction of motion has changed and the law of conservation of momentum gives an expression for the absolute value of the change in momentum (Fig.2.4)()212sin /2p p p m υ∆=-=Θ （2.1）Where m is the mass of the particle, and υ its speed.From Newton ’s second law,this change of momentum must be equal to the force acting on the particle, integrated over the whole time that the particle is in the field of the nucleus. Therefore,02sin(/2)p m Fdt υ∞∆=Θ=⎰ （2.2） Figure 2.3shows the direction of F a particular position of the particle, defined by through angle φ, as shown, by symmetry, it can be seen that the integral in (2.2) is given by00cos I Fdt F dt ϕ∞∞==⎰⎰ (since the integral of the component parallel to the χ-axis, F sin φ, must be zero, by symmetry ).Fig 2.4 Change in momentum of an α particle during interaction with through nucleus.A change of variables for integration enables (2.2) to be rewritten:()()/2()/22sin /2cos (/)m F dt d d ππυϕϕϕ-Θ--ΘΘ=⎰ （2.3）(see Fig 2.3 for the changed limits of integration).Finally, (dt/d φ) is equal to 1/ω where ω is the angular speed of the particle about the origin. Since the force acting on the particle is radial, the angular momentum of the particle is the same for any value of φ, and ω must be given by the equation2mr m b ωυ=Therefore2(/)/dt d r b ϕυ=Coulomb ’s law gives2202/4F Ze r πε=so that substituting in (2.3) and integrating through right hand side gives an expression for Θ in terms of υ and b220cot(/2)(2/)m Ze b πευΘ= （2.4）or, in terms of the kinetic energy T of the particle20cot(/2)(4/)T Ze b πεΘ= （2.5）This gives an equation for the scattering angle in terms of the kinetic energy and impact parameter of the particle and of the charge on the nucleus, Ze.介绍虽然希腊哲学家德谟克利特曾推测了在公元前一世纪原子的存在和道尔顿的原子理论1807年奠定了原子的存在,在20世纪之交以前。
模具 塑料注射成型 外文翻译 外文文献 英文文献
模具塑料注射成型外文翻译外文文献英文文献XXXThere are many different processing methods used to convert plastic pellets。
powders。
and liquids into final products。
Plastic materials XXX。
thermoplastic materials XXX。
XXX require other methods。
It is XXX.XXX。
It is also the oldest method。
Suddenly。
XXX account for 30% of all XXX suitable for mass n。
when raw materials XXX in a single step of n。
In most cases。
n machiningis not required for such products。
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模具外文翻译外文文献英文文献注塑模
模具外文翻译外文文献英文文献注塑模The Injection Molding1、The injection moldingInjection molding is principally used for the production of the thermoplastic parts,although some progress has been made in developing a method for injection molding some thermosetting materials.The problem of injection a method plastic into a mold cavity from a reservoir of melted material has been extremely difficult to solve for thermosetting plastic which cure and harden under such conditions within a few minutes.The principle of injection molding is quite similar to that of die-casting.The process consists of feeding a plastic compound in powered or granular form from a hopper through metering and melting stages and then injecting it into a mold.After a brief cooling period,the mold is opened and the solidified part ejected.Injection-molding machine operation.The advantage of injection molding are：（ⅰ）a high molding speed adapter for mass production is possible；（ⅱ）there is a wide choice of thermoplastic materials providing a variety of useful properties；（ⅲ）it is possible to mold threads,undercuts,side holes,and large thin section.2、The injection-molding machineSeveral methods are used to force or inject the melted plastic into the mold.The most commonly used system in the larger machines is the in-line reciprocating screw,as shown in Figure 2-1.The screw acts as a combination injection and plasticizing unit.As the plastic is fed to the rotating screw,it passes through three zones as shown：feed,compression,and metering.After the feed zone,the screw-flight depth is gradually reduced,force theplastic to compress.The work is converted to heat by conduction from the barrel surface.As the chamber in front of the screw becomes filled,it forces the screw back,tripping a limit switch that activates a hydraulic cylinder that forces the screw forward and injects the fluid plastic into the closed mold.An antiflowback valve presents plastic under pressure from escaping back into the screw flight.The clamping force that a machine is capable of exerting is part of the size designation and is measured in tons.A rule-of-thumb can be used to determine the tonnage required for a particular job.It is based on two tons of clamp force per square inch of projected area.If the flow pattern is difficult and the parts are thin,this may have to go to three or four tons.Many reciprocating-screw machines are capable of handing thermosetting plastic materials.Previously these materials were handled by compression or transfer molding.Thermosetting materials cure or polymerize in the mold and are ejected hot in the range of 375°C～410°C.T hermosetting parts must be allowed to cool in the mold in order or remove them without distortion. Thus thermosetting cycles can be faster.Of course the mold must be heated rather than chilled,as with thermoplastics.3、Basic Underfeed MouldA simple mould of this type is shown in Figure3-1,and the description of the design and the opening sequence follows.The mould consists of three basic parts,namely：the moving half,the floating cavity plate and the feed plate respectively.The moving half consists of The moving mould plate assembly,support block,backing plate,ejector assembly and the pin ejection system.Thus the moving half in this design is identical with the moving half of basic moulds.The floating cavity plate,which may be of the integer or insert-bolster design,is located on substantial guide pillars（not shown）fitted in the feed plate.These guide pillars must be of sufficient length to support the floating cavity plate over its full movement and still project to perform the function of alignment between the cavity and core when the mould is being closed.Guide bushes are fitted into the moving mould plate and the floating cavity plate respectively.The maximum movement of the floating cavity plate is controlled by stop or similar device.The moving mould plate is suitably bored to provide a clearance for the stop bolt assembly.The stop bolts must be long enough to provide sufficient space between the feed plate and the floating cavity plate for easy removal of the feed system.The minimum space provide for should be 65mm just sufficient for an operator to remove the feed system by hand if necessary.The desire operating sequence is for the first daylight to occur between the floating cavity plate.This ensures the sprue is pulled from the sprue bush immediately the mouldis opened.T o achieve this sequence,springs may be incorporated between the feed plate and the floating cavity plate.The springs should be strong enough to give an initial impetus to the floating cavity plate to ensure it moves away with the moving half.It is normal practice to mount the springs on the guide pillars（Figure3-2）and accommodate them in suitable pocket in the cavity plate.The major part of the feed system（runner and sprue）is accommodated in the feed plate to facilitate automatic operation,the runner should be of a trapezoidal form so that once it is pulled from the feed plate is can easily beextracted.Note that if a round runner is used,half the runner is formed in the floating cavity plate,where it would remain,and be prevented from falling or being wiped clear when the mould is opened.Now that we have considered the mould assembly in the some detail,we look at the cycle of operation for this type of mould.The impressions are filled via the feed system（Figure3-1（a））and after a suitable dwell period,the machine platens commence to open.A force is immediately exerted by the compression springs,which cause the floating cavity plate to move away with the moving half as previously discussed.The sprue is pulled from the sprue bush by the sprue puller.After the floating cavity plate has moved a predetermined distance,it is arrested by the stop bolts.The moving half continues to move back and the moldings,having shrunk on to the cores,are withdrawn from the cavities.The pin gate breaks at its junction with the runner（Figure3-1（b））.The sprue puller,being attached to the moving half,is pulled through the floating cavity plate and thereby release the feed system which is then free to fall between the floating cavity plate and the feed plate.The moving half continues to move back until the ejector system is operated and the moldings are ejected （Figure3-1（c））.When the mould is closed,the respective plates are returned to their molding position and the cycle is repeated.4、Feed SystemIt is necessary to provide a flow-way in the injection mould to connect the nozzle（of the injection machine）to each impression.This flow-way is termed the feed system.Normally thefeed system comprises a sprue,runner and gate.These terms applyequally to the flow-way itself,and to the molded material which is remove from the flow-way itself in the process of extracted the molding.A typical feed system for a four-impression,two plate-type mould is shown in Figure4-1.It is seen that the material passes through the sprue,main runner,branch runner and gate before entering the impression.As the temperature of molten plastic is lowered which going through the sprue and runner,the viscosity will rise;however,the viscosity is lowered by shear heat generated when going through the gate to fill the cavity.It is desirable to keep the distance that the material has to travel down to a minimum to reduce pressure and heat losses.It is for this reason that careful consideration must be given to the impression layout gate’s design.4.1.SprueA sprue is a channel through which to transfer molten plastic injected from the nozzle of the injector into the mold.It is a part of sprue bush,which is a separate part from the mold.4.2.RunnerA runner is a channel that guides molten plastic into the cavity of a mold.4.3.GateA gate is an entrance through which molten plastic enters the cavity.The gate has the following function：restricts the flow and the direction of molten plastic；simplifies cutting of a runner and moldings to simplify finishing of parts；quickly cools and solidifies to avoid backflow after molten plastic has filled up in the cavity.4.4.Cold slug wellThe purpose of the cold slug well,shown opposite the sprue,is theoretically to receive the material that has chilled at the front of nozzle during the cooling and ejection phase.Perhaps of greater importance is the fact that it provides position means whereby the sprue bush for ejection purposes.The sprue,the runner and the gate will be discarded after a part is complete.However,the runner and the gate are important items that affect the quality or the cost of parts.5、EjectionA molding is formed in mould by injecting a plastic melt,under pressure,into animpression via a feed system.It must therefore be removed manually.Furthermore,all thermoplastic materials contract as they solidify,which means that the molding will shrink on to the core which forms it.This shrinkage makes the molding difficult to remove. Facilities are provided on the injection machine for automatic actuation of an ejector system,and this is situated behind the moving platen.Because of this,the mould’s ejector system will be most effectively operated if placed in the moving half of the mould,i.e. the half attached to the moving platen.We have stated previously that we need to eject the molding from the core and it therefore follows that the core,too,will most satisfactorily be located in the moving half.The ejector system in a mould will be discussed under three headings,namely：（ⅰ）the ejector grid;（ⅱ）the ejector plate assembly; and（ⅲ）the method of ejection.5.1、Ejector gridThe ejector grid（Figure5-1）is that part of the mould which supports the mould plate and provides a space into which theejector plate assembly can be fitted and operated.The grid normally consists of a back plate on to which is mounted a number of conveniently shaped “support blocks”.The ejector plate assembly is that part of the mould to which the ejector element is attached.The assembly is contained in a pocket,formed by the ejector grid,directly behind the mould plate.The assembly（Figure5-2）consists of an ejector plate,a retaining plate and an ejector rod.One end of this latter member is threaded and it is screwed into the ejector plate.In this particular design the ejector rod function not only as an actuating member but also as a method of guiding the assembly.Note that the parallel portion of the ejector rod passes through an ejector rod bush fitted in the back plate of the mould.5.2、Ejection techniquesWhen a molding cools,it contracts by an amount depending on the material being processed.For a molding which has no internal form,for example,a solid rectangular block,the molding will shrink away from the cavity walls,thereby permitting a simple ejection technique to be adopted.However,when the molding has internal form,the molding,as it cools,will shrink onto the core and some positive type of ejection is necessary.The designer has several ejection techniques from which to choose，but in general,the choice will be restricted depending upon the shape of the molding.The basic ejection techniques are as follows：（ⅰ）pin ejection（ⅱ）sleeve ejection（ⅲ）stripper plate ejection and（Ⅳ）air ejection.Figure 2-1aFigure 2-1bFigure 3-1Figure 3-2Figure 4-1aFigure 4-1bFigure 5-1Figure 5-2注塑模1、注塑模尽管成型某些热固性材料的方法取得了一定的进步，但注塑模主要（还是）用来生产热塑性塑件。
注塑模具设计与制造外文文献翻译
2 Injection molding machineFrom Plastics Wiki, free encyclopediaInjection molding machines consist of two basic parts, an injection unit and a clamping unit. Injection molding machines differ in both injection unit and clamping unit. The name of the injection molding machine is generally based on the type of injection unit used.2.1Types of injection molding machinesMachines are classified primarily by the type of driving systems they use: hydraulic, electric, or hybrid.2.1.1HydraulicHydraulic presses have historically been the only option available to molders until Nissei Plastic Industrial Co., LTD introduced the first all-electric injection molding machine in 1983. The electric press, also known as Electric Machine Technology (EMT), reduces operation costs by cutting energy consumption and also addresses some of the environmental concerns surrounding the hydraulic press.2.1.2ElectricElectric presses have been shown to be quieter, faster, and have a higher accuracy, however the machines are more expensive.2.1.3HybridHybrid injection molding machines take advantage of the best features of both hydraulic and electric systems. Hydraulic machines are the predominant type in most of the world, with the exception of Japan.2.2Injection unitThe injection unit melts the polymer resin and injects the polymer melt into the mold. The unit may be: ram fed or screw fed.The ram fed injection molding machine uses a hydraulically operated plunger to push the plastic through a heated region. The high viscosity melt is then spread into a thin layer by a "torpedo" to allow for better contact with the heated surfaces. The melt converges at a nozzle and is injected into the mold.Reciprocating screw A combination melting, softening, and injection unit in an injection molding machine. Another term for the injection screw. Reciprocating screws are capable of turning as they move back and forth.The reciprocating screw is used to compress, melt, and convey the material. The reciprocating screw consists of three zones (illustrated below):•feeding zone•compressing zone•metering zoneWhile the outside diameter of the screw remains constant, the depth of the flights on the reciprocating screw decreases from the feed zone to the beginning of the metering zone. These flights compress the material against the inside diameter of the barrel, which creates viscous (shear) heat. This shear heat is mainly responsible for melting the material. The heater bands outside the barrel help maintain the material in the molten state. Typically, a molding machine can have three or more heater bands or zones with different temperature settings.Injection molding reciprocating screw An extruder-type screw rotates within a cylinder, which is typically driven by a hydraulic drive mechanism. Plastic material is moved through the heated cylinder via the screw flights and the material becomes fluid. The injection nozzle is blocked by the previous shot, and this action causes the screw to pump itself backward through the cylinder. (During this step, material is plasticated and accumulated for the next shot.) When the mold clamp has locked, the injection phase takes place. At this time, the screw advances, acting as a ram. Simultaneously, the non-return valve closes off the escape passages in the screw and the screw serves as a solid plunger, moving the plastic ahead into the mold. When the injection stroke and holding cycle is completed, the screw is energized to return and the non-return valve opens, allowing plastic to flow forward from the cylinder again, thus repeating the cycle.2.2.1Feed hopperThe container holding a supply molding material to be fed to the screw. The hopper located over the barrel and the feed throat connects them.2.2.2Injection ramThe ram or screw that applies pressure on the molten plastic material to force it into the mold cavities.2.2.3Injection screwThe reciprocating-screw machine is the most common. This design uses the same barrel for melting and injection of plastic.The alternative unit involves the use of separate barrels for plasticizing and injecting the polymer. This type is called a screw-preplasticizer machine or two-stage machine. Plastic pellets are fed from a hopper into the first stage, which uses a screw to drive the polymer forward and melt it. This barrel feeds a second barrel, which uses a plunger to inject the melt into the mold. Older machines used one plunger-driven barrel to melt and inject the plastic. These machines are referred to as plunger-type injection molding machines.2.2.4BarrelBarrel is a major part that melts resins transmitted from hopper through screws and structured in a way that can heat up resins to the proper temperature. A band heater, which can control temper atures in five sections, is attached outside the barrel. Melted resins are supplied to the mold passing through barrel head, shot-off nozzle, and one-touch nozzle.2.2.5Injection cylinderHydraulic motor located inside bearing box, which is connected to injection cylinder load, rotates screw, and the melted resins are measures at the nose of screw. There are many types of injection cylinders that supply necessary power to inject resins according to the characteristics of resins and product types at appropriate speed and pressure. This model employs the double cylinder type. Injection cylinder is composed of cylinder body, piston, and piston load.2.3Clamping unitThe clamping unit holds the mold together, opens and closes it automatically, and ejects the finished part. The mechanism may be of several designs, either mechanical, hydraulic or hydromechanical.Toggle clamps - a type clamping unit include various designs. An actuator moves the crosshead forward, extending the toggle links to push the moving platen toward a closed position. At the beginning of the movement, mechanical advantage is low and speed is high; but near the end of the stroke, the reverse is true. Thus, toggle clamps provide both high speed and high force at different points in the cycle when they are desirable. They are actuated either by hydraulic cylinders or ball screws driven by electric motors. Toggle-clamp units seem most suited to relatively low-tonnage machines.Two clamping designs: (a) one possible toggle clamp design (1) open and (2) closed; and (b) hydraulic clamping (1) open and (2) closed. Tie rods used to guide movuing platens not shown.Hydraulic clamps are used on higher-tonnage injection molding machines, typically in the range 1300 to 8900 kN (150 to 1000 tons). These units are also more flexible than toggle clamps in terms of setting the tonnage at given positions during the stroke.Hydraulic Clamping System is using the direct hydraulic clamp of which the tolerance is still and below 1 %, of course, better than the toggle system. In addition, the Low Pressure Protection Device is higher than the toggle system for 10 times so that the protection for the precision and expensive mold is very good. The clamping force is focus on the central for evenly distribution that can make the adjustment of the mold flatness in automatically. Hydromechanical clamps -clamping units are designed for large tonnages, usually above 8900 kN (1000 tons); they operate by (1) using hydraulic cylinders to rapidly move the mold toward closing position, (2) locking the position by mechanical means, and (3) using high pressure hydraulic cylinders to finally close the mold and build tonnage.2.3.1Injection moldThere are two main types of injection molds: cold runner (two plate and three plate designs) and hot runner– the more common of the runnerless molds.2.3.2Injection platensSteel plates on a molding machine to which the mold is attached. Generally, two platens are used; one being stationary and the other moveable, actuated hydraulically to open and close the mold. It actually provide place to mount the mould. It contains threaded holes on which mould can be mounted using clamps.2.3.3Clamping cylinderA device that actuates the chuck through the aid of pneumatic or hydraulic energy.2.3.4Tie BarTie bars support clamping power, and 4 tie bars are located between the fixing platen and the support platen.3 Injection mouldFrom Wikipedia, the free encyclopediaMold A hollow form or cavity into which molten plastic is forced to give the shape of the required component. The term generally refers to the whole assembly of parts that make up the section of the molding equipment in which the parts are formed. Also called a tool or die. Moulds separate into at least two halves (called the core and the cavity) to permit the part to be extracted; in general the shape of a part must be such that it will not be locked into the mould. For example, sides of objects typically cannot be parallel with the direction of draw (the direction in which the core and cavity separate from each other). They are angled slightly; examination of most household objects made from plastic will show this aspect of design, known as draft. Parts that are "bucket-like" tend to shrink onto the core while cooling and, after the cavity is pulled away, are typically ejected using pins. Parts can be easily welded together after moulding to allow for a hollow part (like a water jug or doll's head) that couldn't physically be designed as one mould.More complex parts are formed using more complex moulds, which may require moveable sections, called slides, which are inserted into the mould to form particular features that cannot be formed using only a core and a cavity, but are then withdrawn to allow the part to be released. Some moulds even allow previously moulded parts to be re-inserted to allow a new plastic layer to form around the first part. This system can allow for production of fully tyred wheels.Traditionally, moulds have been very expensive to manufacture; therefore, they were usually only used in mass production where thousands of parts are being produced.Molds require: Engineering and design, special materials, machinery and highly skilled personnel to manufacture, assemble and test them.Cold-runner moldCold-runner mold Developed to provide for injection of thermoset material either directly into the cavity or through a small sub-runner and gate into the cavity. It may be compared to the hot-runner molds with the exception that the manifold section is cooled rather than heated to maintain softened but uncured material. The cavity and core plates are electrically heated to normal molding temperature and insulated from the cooler manifold section.3.1.1Types of Cold Runner MoldsThere are two major types of cold runner molds: two plate and three plate.3.1.2Two plate moldA two plate cold runner mold is the simplest type of mold. It is called a two plate mold because there is one parting plane, and the mold splits into two halves. The runner system must be located on this parting plane; thus the part can only be gated on its perimeter.3.1.3Three plate moldA three plate mold differs from a two plate in that it has two parting planes, and the mold splits into three sections every time the part is ejected. Since the mold has two parting planes, the runner system can be located on one, and the part on the other. Three plate molds are used because of their flexibility in gating location. A part can be gated virtually anywhere along its surface.3.1.4AdvantagesThe mold design is very simple, and much cheaper than a hot runner system. The mold requires less maintenance and less skill to set up and operate. Color changes are also very easy, since all of the plastic in the mold is ejected with each cycle.3.1.5DisadvantagesThe obvious disadvantage of this system is the waste plastic generated. The runners are either disposed of, or reground and reprocessed with the original material. This adds a step in the manufacturing process. Also, regrind will increase variation in the injection molding process, and could decrease the plastic's mechanical properties.3.1.6Hot runner moldHot-runner mold -injection mold in which the runners are kept hot and insulated from the chilled cavities. Plastic freezeoff occurs at gate of cavity; runners are in a separate plate so they are not, as is the case usually, ejected with the piece.Hot runner molds are two plate molds with a heated runner system inside one half of the mold.A hot runner system is divided into two parts: the manifold and the drops. The manifold has channels that convey the plastic on a single plane, parallel to the parting line, to a point abovethe cavity. The drops, situated perpendicular to the manifold, convey the plastic from the manifold to the part.3.1.7Types of Hot Runner MoldsThere are many variations of hot runner systems. Generally, hot runner systems are designated by how the plastic is heated. There are internally and externally heated drops and manifolds.3.1.8Externally heated hot runnersExternally heated hot runner channels have the lowest pressure drop of any runner system (because there is no heater obstructing flow and all the plastic is molten), and they are better for color changes none of the plastic in the runner system freezes. There are no places for material to hang up and degrade, so externally heated systems are good for thermally sensitive materials.3.1.9Internally heated hot runnersInternally heated runner systems require higher molding pressures, and color changes are very difficult. There are many places for material to hang up and degrade, so thermally sensitive materials should not be used. Internally heated drops offer better gate tip control. Internally heated systems also better separate runner heat from the mold because an insulating frozen layer is formed against the steel wall on the inside of the flow channels.3.1.10 insulated hot runnersA special type of hot runner system is an insulated runner. An insulated runner is not heated; the runner channels are extremely thick and stay molten during constant cycling. This system is very inexpensive, and offers the flexible gating advantages of other hot runners and the elimination of gates without the added cost of the manifold and drops of a heated hot runner system. Color changes are very easy. Unfortunately, these runner systems offer no control, and only commodity plastics like PP and PE can be used. If the mold stops cycling for some reason, the runner system will freeze and the mold has to be split to remove it. Insulated runners are usually used to make low tolerance parts like cups and frisbees.3.1.11 DisadvantagesHot-runner mold is much more expensive than a cold runner, it requires costly maintenance, and requires more skill to operate. Color changes with hot runner molds can be difficult, since it is virtually impossible to remove all of the plastic from an internal runner system.3.1.12 AdvantagesThey can completely eliminate runner scrap, so there are no runners to sort from the parts, and no runners to throw away or regrind and remix into the original material. Hot runners are popular in high production parts, especially with a lot of cavities.Advantages Hot Runner System Over a Cold Runner System include:•no runners to disconnect from the molded parts•no runners to remove or regrind, thus no need for process/ robotics to remove them•having no runners reduces the possibility of contamination•lower injection pressures•lower clamping pressure•consistent heat at processing temperature within the cavity•cooling time is actually shorter (as there is no need for thicker, longer-cycle runners)•shot size is reduced by runner weight•cleaner molding process (no regrinding necessary)•nozzle freeze and sprue sticking issues eliminated中文翻译注塑模具设计与制造2 注射机选自《维基百科》注射机由两个基本部分组成，注射装置和夹紧装置。
在注塑模应用方面,外形电铸镍的技术注释外文翻译、中英文翻译、外文文献翻译
南京理工大学泰州科技学院毕业设计(论文)外文资料翻译系部：机械工程系专业：机械工程及自动化姓名：王锋学号： 05010230外文出处：中国机械资讯网附件： 1.外文资料翻译译文；2.外文原文。
指导教师评语：译文基本符合翻译原文,个别词汇不符合语境。
语句较为通顺，条理比较清楚，专业用语翻译基本恰当，符合中文语法，整体翻译质量较好。
签名：年月日附件1：外文资料翻译译文在注塑模应用方面，外形电铸镍的技术注释摘要在过去几年，快速成型技术及快速模具在发达国家已广泛应用。
在这篇文章中,作为一种范例，分析电芯塑料注射模具。
通过快速成型，利用差分系统得到镍壳模型。
主要目的是分析镍壳力学特征，学习不同方面的金相组织、硬度、内压，失败的可能性。
以这些特色的有关参数生产镍壳电设备，终于得到了一个注塑模具核心部分。
关键词：电镀；电制；显微组织；镍文章概要1. 引言2. 注塑模具制造过程3.电铸壳获取：设备4. 获得硬度5. 金相组织6. 内压7.测试的注塑模具8. 结论1．引言现代工业遇到的最重要的挑战之一是在很短的时间内向消费者提供更好的产品。
因此,现代工业必须有更强的竞争性和适应更合理的生产成本。
毫无疑问，结合时间和质量并不容易,因为他们经常互相变换。
生产系统的科技进步，在方式将可更有效和可行的促进组合,例如,如果是演化的观测系统和注塑技术、我们得出的结论是事实上可以用很少的时间和高质量把新产品推向市场。
在模具制造领域中，先进的快速模具制造技术有可能改善设计和制造过程注入部分。
快速模具制造技术基本上是由程序集中组成，在短短的时间里，以可接受的精度水平使我们获取小型系列的塑料模具零件。
其应用领域不仅包括制作塑胶件注，而且他们研制并创造了最高产量。
本文包括在广泛试图研究确定分析测试和建议的科研第一线，在产业层次形成从注塑模具获取镍壳核心的可能性，同时用差分模型快速成型设备取得了初步的模型。
也将不得不说，无数业内人士事前并没有应用任何新电铸技术，但很大程度上，在快速模具的生产技术上使用这种试图调查研究工作.，运用所有准确，制度化的方式方法并提出了工作。
文献翻译原文-一个描述电铸镍壳在注塑模具的应用的技术研究
编号：毕业设计(论文)外文翻译（原文）学院：国防生学院专业：机械设计制造及其自动化学生姓名：学号：指导教师单位：姓名：职称：2014年 3 月9 日technical note on the characterization of electroformed nickel shells for their application to injection molds——a Universidad de Las Palmas de Gran Canaria, Departamento de Ingenieria Mecanica, SpainAbstractThe techniques of rapid prototyping and rapid tooling have been widely developed during the last years. In this article, electroforming as a procedure to make cores for plastics injection molds is analysed. Shells are obtained from models manufactured through rapid prototyping using the FDM system. The main objective is to analyze the mechanical features of electroformed nickel shells, studying different aspects related to their metallographic structure, hardness, internal stresses and possible failures, by relating these features to the parameters of production of the shells with an electroforming equipment. Finally a core was tested in an injection mold. Keywords: Electroplating; Electroforming; Microstructure; Nickel1. IntroductionOne of the most important challenges with which modern industry comes across is to offer the consumer better products with outstanding variety and time variability (new designs). For this reason, modern industry must be more and more competitive and it has to produce with acceptable costs. There is no doubt that combining the time variable and the quality variable is not easy because they frequently condition one another; the technological advances in the productive systems are going to permit that combination to be more efficient and feasible in a way that, for example, if it is observed the evolution of the systems and techniques of plastics injection, we arrive at the conclusion that, in fact, it takes less and less time to put a new product on the market and with higher levels of quality. The manufacturing technology of rapid tooling is, in this field, one of those technological advances that makes possible the improvements in the processes of designing and manufacturing injected parts. Rapid tooling techniques are basically composed of a collection of procedures that are going to allow us to obtain a mold of plastic parts, in small or medium series, in a short period of time and with acceptable accuracy levels. Their application is not only included in the field of making plastic injected pieces [1], [2] and [3], however, it is true that it is where they have developed more and where they find the highest output. This paper is included within a wider research line where it attempts to study, define, analyze, test and propose, at an industrial level, the possibility of creating cores forinjection molds starting from obtaining electroformed nickel shells, taking as an initial model a prototype made in a FDM rapid prototyping equipment.It also would have to say beforehand that the electroforming technique is not something new because its applications in the industry are countless [3], but this research work has tried to investigate to what extent and under which parameters the use of this technique in the production of rapid molds is technically feasible. All made in an accurate and systematized way of use and proposing a working method.2. Manufacturing process of an injection moldThe core is formed by a thin nickel shell that is obtained through the electroforming process, and that is filled with an epoxic resin with metallic charge during the integration in the core plate [4] This mold (Fig. 1) permits the direct manufacturing by injection of a type a multiple use specimen, as they are defined by the UNE-EN ISO 3167 standard. The purpose of this specimen is to determine the mechanical properties of a collection of materials representative industry, injected in these tools and its coMParison with the properties obtained by conventional tools.Fig. 1. Manufactured injection mold with electroformed core.The stages to obtain a core [4], according to the methodology researched in this work, are the following:(a) Design in CAD system of the desired object.(b) Model manufacturing in a rapid prototyping equipment (FDM system). The material used will be an ABS plastic.(c) Manufacturing of a nickel electroformed shell starting from the previous model that has been coated with a conductive paint beforehand (it must have electrical conductivity).(d) Removal of the shell from the model.(e) Production of the core by filling the back of the shell with epoxy resin resistant to high temperatures and with the refrigerating ducts made with copper tubes.The injection mold had two cavities, one of them was the electroformed core and the other was directly machined in the moving platen. Thus, it was obtained, with the same tool and in the same process conditions, to inject simultaneously two specimens in cavities manufactured with different technologies.3. Obtaining an electroformed shell: the equipmentElectrodeposition [5] and [6] is an electrochemical process in which a chemical change has its origin within an electrolyte when passing an electric current through it. The electrolytic bath is formed by metal salts with two submerged electrodes, an anode (nickel) and a cathode (model), through which it is made to pass an intensity coming from a DC current. When the current flows through the circuit, the metal ions present in the solution are transformed into atoms that are settled on the cathode creating a more or less uniform deposit layer.The plating bath used in this work is formed by nickel sulfamate [7] and [8] at a concentration of 400 ml/l, nickel chloride (10 g/l), boric acid (50 g/l), Allbrite SLA (30 cc/l) and Allbrite 703 (2 cc/l). The selection of this composition is mainly due to the type of application we intend, that is to say, injection molds, even when the injection is made with fibreglass. Nickel sulfamate allows us to obtain an acceptable level of internal stresses in the shell (the tests gave results, for different process conditions, not superior to 50 MPa and for optimum conditions around 2 MPa). Nevertheless, such level of internal pressure is also a consequence of using as an additive Allbrite SLA, which is a stress reducer constituted by derivatives of toluenesulfonamide and by formaldehyde in aqueous solution. Such additive also favours the increase of the resistance of the shell when permitting a smaller grain. Allbrite 703 is an aqueous solution of biodegradable surface-acting agents that has been utilized to reduce the risk of pitting. Nickel chloride, in spite of being harmful for the internal stresses, is added to enhance the conductivity of the solution and to favour the uniformity in the metallic distribution in the cathode. The boric acid acts as a pH buffer.The equipment used to manufacture the nickel shells tested has been as follows:• Polypropylene tank: 600 mm × 400 mm × 500 mm in size.• Three teflon resistors, each one with 800 W.• Mechanical stirring system of the cathode.• System for recirculation and f iltration of the bath formed by a pump and a polypropylene filter.• Charging rectifier. Maximum intensity in continuous 50 A and continuous current voltage between 0 and 16 V.• Titanium basket with nickel anodes (Inco S-Rounds Electrolytic Nickel) with a purity of 99%.• Gases aspiration system.Once the bath has been defined, the operative parameters that have been altered for testing different conditions of the process have been the current density (between 1 and 22 A/dm2), the temperature (between 35 and 55 °C) and the pH, partially modifying the bath composition.4. Obtained hardnessOne of the most interesting conclusions obtained during the tests has been that the level of hardness of the different electroformed shells has remained at rather high and stable values. In Fig. 2, it can be observed the way in which for current density values between 2.5 and 22 A/dm2, the hardness values range from 540 and 580 HV, at pH4 ± 0.2 and with a temperature of 45 °C. If the pH of the bath is reduced at 3.5 and the temperature is 55 °C those values are above 520 HV and below 560 HV. This feature makes the tested bath different from other conventional ones composed by nickel sulfamate, allowing to operate with a wider range of values; nevertheless, such operativity will be limited depending on other factors, such as internal stress because its variability may condition the work at certain values of pH, current density or temperature. On the other hand, the hardness of a conventional sulfamate bath is between 200–250 HV, much lower than the one obtained in the tests. It is necessary to take into account that, for an injection mold, the hardness is acceptable starting from 300 HV. Among the most usual materials for injection molds it is possible to find steel for improvement (290 HV), steel for integral hardening (520–595 HV), casehardened steel (760–800 HV), etc., in such a way that it can be observed that the hardness levels of the nickel shells would be within the medium–high range of the materials for injection molds. The objection to the low ductility of the shell is compensated in such a way with the epoxy resin filling that would follow it because this is the one responsible for holding inwardly the pressure charges of the processes of plastics injection; this is the reason why it is necessary for the shell to have a thickness as homogeneous as possible (above a minimum value) and with absence of important failures such as pitting.Fig. 2. Hardness variation with current density. pH 4 ± 0.2, T = 45 °C.5. Metallographic structureIn order to analyze the metallographic structure, the values of current density and temperature were mainly modified. The samples were analyzed in frontal section and in transversal section (perpendicular to the deposition). For achieving a convenient preparation, they were conveniently encapsulated in resin, polished and etched in different stages with a mixture of acetic acid and nitric acid. The etches are carried out at intervals of 15, 25, 40 and 50 s, after being polished again, in order to be observed afterwards in a metallographic microscope Olympus PME3-ADL 3.3×/10×.Before going on to comment the photographs shown in this article, it is necessary to say that the models used to manufacture the shells were made in a FDM rapid prototyping machine where the molten plastic material (ABS), that later solidifies, is settled layer by layer. In each layer, the extruder die leaves a thread approximately 0.15 mm in diameter which is compacted horizontal and vertically with the thread settled inmediately after. Thus, in the surface it can be observed thin lines that indicate the roads followed by the head of the machine. These lines are going to act as a reference to indicate the reproducibility level of the nickel settled. The reproducibility of the model is going to be a fundamental element to evaluate a basic aspect of injection molds: the surface texture.The tested series are indicated in Table 1.Table 1.Tested seriesSeries pH Temperature(°C) Current density (A/dm2)1 4.2 ± 0.2 55 2.222 3.9 ± 0.2 45 5.563 4.0 ± 0.2 45 10.004 4.0 ± 0.2 45 22.22Fig. 3 illustrates the surface of a sample of the series after the first etch. It shows the roads originated by the FDM machine, that is to say that there is a good reproducibility. It cannot be still noticed the rounded grain structure. In Fig. 4, series 2, after a second etch, it can be observed a line of the road in a way less clear than in the previous case. In Fig. 5, series 3 and 2° etch it begins to appear the rounded grainstructure although it is very difficult to check the roads at this time. Besides, the most darkened areas indicate the presence of pitting by inadequate conditions of process and bath composition.Fig. 3. Series 1 (×150), etch 1.Fig. 4. Series 2 (×300), etch 2.Fig. 5. Series 3 (×300), etch 2.This behavior indicates that, working at a low current density and a high temperature, shells with a good reproducibility of the model and with a small grain size are obtained, that is, adequate for the required application.If the analysis is carried out in a plane transversal to the deposition, it can be tested in all the samples and for all the conditions that the growth structure of the deposit is laminar (Fig. 6), what is very satisfactory to obtain a high mechanical resistance although at the expense of a low ductibility. This quality is due, above all, to the presence of the additives used because a nickel sulfamate bath without additives normally creates a fibrous and non-laminar structure [9]. The modification until a nearly null value of the wetting agent gave as a result that the laminar structure was maintained in any case, that matter demonstrated that the determinant for such structure was the stress reducer (Allbrite SLA). On the other hand, it was also tested that the laminar structure varies according to the thickness of the layer in terms of the current density.Fig. 6. Plane transversal of series 2 (×600), etch 2.6. Internal stressesOne of the main characteristic that a shell should have for its application like an insert is to have a low level of internal stresses. Different tests at different bath temperatures and current densities were done and a measure system rested on cathode flexural tensiometer method was used. A steel testing control was used with a side fixed and the other free (160 mm length, 12.7 mm width and thickness 0.3 mm). Because the metallic deposition is only in one side the testing control has a mechanical strain (tensile or compressive stress) that allows to calculate the internal stresses. Stoney model [10] was applied and was supposed that nickel substratum thickness is enough small (3 μm) to influence, in an elastic point of view, to the strained steel part. In all the tested cases the most value of internal stress was under 50 MPa for extreme conditions and 2 MPa for optimal conditions, an acceptable value for the required application. The conclusion is that the electrolitic bath allows to work at different conditions and parameters without a significant variation of internal stresses.7. Test of the injection moldTests have been carried out with various representative thermoplastic materials such as PP, PA, HDPE and PC, and it has been analysed the properties of the injected parts such as dimensions, weight, resistance, rigidity and ductility. Mechanical properties were tested by tensile destructive tests and analysis by photoelasticity. About 500 injections were carried out on this core, remaining under conditions of withstanding many more.In general terms, important differences were not noticed between the behavior of the specimens obtained in the core and the ones from the machined cavity, for the set of the analysed materials. However in the analysis by photoelasticiy (Fig. 7) it was noticed a different tensional state between both types of specimens, basically due to differences in the heat transference and rigidity of the respective mold cavities. This difference explains the ductility variations more outstanding in the partially crystalline materials such as HDPE and PA 6.Fig. 7. Analysis by photoelasticity of injected specimens.For the case of HDPE in all the analysed tested tubes it was noticed a lower ductility in the specimens obtained in the nickel core, quantified about 30%. In the case of PA 6 this value was around 50%.8. ConclusionsAfter consecutive tests and in different conditions it has been checked that the nickel sulfamate bath, with the utilized additives has allowed to obtain nickel shells with some mechanical properties acceptable for the required application, injection molds, that is to say, good reproducibility, high level of hardness and good mechanical resistance in terms of the resultant laminar structure. The mechanical deficiencies of the nickel shell will be partially replaced by the epoxy resin that finishes shaping the core for the injection mold, allowing to inject medium series of plastic parts with acceptable quality levels.References[1] A.E.W. Rennie, C.E. Bocking and G.R. Bennet, Electroforming of rapid prototyping mandrels for electro discharge machining electrodes, J. Mater. Process. Technol.110 (2001), pp. 186–196. [2] P.K.D.V. Yarlagadda, I.P. Ilyas and P. Chrstodoulou, Development of rapid tooling for sheet metal drawing using nickel electroforming and stereo lithography processes, J. Mater. Process. Technol.111 (2001), pp. 286–294.[3] J. Hart, A. Watson, Electroforming: A largely unrecognised but expanding vital industry, Interfinish 96, 14 World Congress, Birmingham, UK, 1996.[4] M. Monzón et al., Aplicación del electroconformado en la fabricación rápida de moldes de inyección, Revista de Plásticos Modernos.84 (2002), p. 557.[5] L.F. Hamilton et al., Cálculos de Química Analítica, McGraw Hill (1989).[6] E. Julve, Electrodeposición de metales, 2000 (E.J.S.).[7] A. Watson, Nickel Sulphamate Solutions, Nickel Development Institute (1989).[8] A. Watson, Additions to Sulphamate Nickel Solutions, Nickel Development Institute (1989).[9] J. Dini, Electrodeposition Materials Science of Coating and Substrates, Noyes Publications (1993).[10] J.W. Judy, Magnetic microactuators with polysilicon flexures, Masters Report, Department of EECS, University of California, Berkeley, 1994. (cap′. 3).How Surface Treatments Keep Molds Operating LongerImportant tips and information about mold coatings to help you achieve the level ofproduction that you and your customers desire.By Steven . Bales Mold making technology January 2006AbstractThere’s an awful lot to know these days about molding plastic and how to get the very best performance from the valuable tools you build or run. This guide has been written to provide important tips and information about mold coatings. After reading this, you should have a very good idea of what coatings—from the very traditional to the very latest—will help you to achieve the level of production you and yourcustomers desire. After all, these tools are an investment and they need to be protected for the life of the products they mold.Key Wordsmold coatings preventive maintenance (PM) program benefit nickel Cobalt diamond-chromenickel-PTFE nickel-boron nitride electroless nickel textureThe Key Role of CoatingsBefore introducing you to the wide range of coatings on the market today, it’s important to note the role coatings can play in an effective preventive maintenance (PM) program.PM is really the key to protecting your tooling, your investment. Why? Because it saves time and money. Once you invest in a mold coating to improve tool performance, then a PM program is always a good idea to ensure you get the maximum benefit. These two steps should be a given in any shop.Remember, no coating lasts forever, and producing substandard parts from a mold with a worn coating is no way to win customers and stay profitable. PM is probably the most cost-effective strategy you can put in place. The key is to educate your personnel on how mold coatings wear during production. Every coating is different, so it’s of benefit to have employees learn how to tell when the coating is showing deterioration, especially in high-wear areas such as gates and runners.For example, wear in and around gate areas plated with hard chrome is the first sign that your mold needs servicing. How can you tell there is wear? The chrome coating is approximately 20 RC points harder than the base steel, so exposed steel will wear much faster than the coated surfaces surrounding it, causing a slight or pronounced edge or ―step‖ on the surface.Conversely, nickel will wear almost evenly, causing a kind of feathering effect, making it more difficult to recognize wear. A more identifiable difference will be the color because when nickel coating wears, it produces a shadow or halo effect on the steel. No step or edge will be evident. The steel also will have a more silver appearance compared to the somewhat tarnished look of the nickel coating.This knowledge makes pulling a mold for maintenance before the coating wears through an ultra important aspect of a PM program. To miss important wear signals means more costly repairs and additional polishing expense.Measuring WearA recommended tool for measuring the wear level of any coating is an electronic thickness gauge that uses a combination of magnetism and eddy current to accurately measure surface thickness. When the mold first arrives in your plant, take the time to measure the surface thickness—especially in high-wear areas—using this specialized tool. As you run production on the mold, occasionally pause to re-measure those areas. When you have determined that the finish is wearing to a critical level, pull the mold and send it out for maintenance.Part CountsBe sure to record the measurements taken with the thickness gauge and use the notes to create a history of maintenance requirements for the tool. A cycle counter installed on the mold will allow your tooling engineer to record wear levels as compared to piece part counts, thereby doubling the effectiveness of your PM program. Part counts are a great way to determine maintenance needs, especially with high-volume molding projects.From the very first time you run the mold, keep an accurate piece count until it is ready for its first maintenance work. Use that count as a gauge for when the next maintenance is due. Because you know approximately when the mold will be ready to be refurbished, you can arrange the service in advance with your coating vendor. This not only gives him ample time to schedule your mold maintenance, but it also allows you to optimize the use of the mold and the machine that’s running it.Coating ChallengesEven today, there are those who question the benefits of using fancy—sometimes more expensive—coatings to prolong tooling life or enhance performance. To some, the tried and true hard chrome or electroless nickel are all they’ll ever need to accomplish those goa ls. But we all know that today’s engineered plastic materials can be pretty rough on injection molds.Challenges to mold maintenance extend beyond glass- and mineral-fillers to include rice hulls, wood fibers, metal powders, flame retardants and other additives—not to mention the resins themselves. In addition, outgassing and moisture acidity often accompany abrasive wear, taking an even bigger toll on expensive tooling.In addition, growing complexity in mold design involves tinier, more intricate flow passages and more frequent use of moving cores and slides. All of these circumstances have prompted the development of a wider variety of mold coatings that can keep molds operating longer between repairs.New Coating ScienceIf you are molding highly intricate parts using glass-filled materials, you might think using hard chrome will be sufficient because it is a classic, reliable way to protect your mold from both corrosion and abrasion. However, hard chrome, for all its benefits, does not tend to plate uniformly in detailed areas like ribs and bosses. There is a newer solution—a nickel-cobalt alloy coating that can overcome that limitation.Nickel CobaltNickel-cobalt can be an economical alternative to hard chrome. Hard chrome requires construction of a conforming anode to coat the mold. The more detail in the mold, the more time it takes to build the anode and the more expensive the process becomes. This nickel-cobalt alloy coating requires no anode, and because of its electroless properties, it plates much more uniformly.The cobalt gives it good abrasion resistance, but its hardness is 62 RC, 10 points lower than hard chrome. Is it worth paying extra for hard chrome’s superior wear protection? You have to consider the material being run in the mold. Wha t’s the percentage of glass? Is corrosion a greater concern than abrasion?Diamond ChromeHard chrome and a nickel-cobalt alloy coating offer two very good solutions for abrasion resistance, but for very high-wear conditions, an even newer product called diamond-chrome offers exceptional protection.It has an RC rating greater than 85 and is a chromium-matrix composite coating with a dispersion of nanometer-size, spherical diamond particles. Since diamonds are unmatched for hardness, this coating offers protection beyond the norm. Though their Rockwell ratings are comparable, diamond-chrome outperforms titanium nitride (TiN) coating because it won’t compromise the dimensional integrity of the plated tool. The difference is that it is applied at only about 130oF while TiN requires application temperatures of 800oF or higher.Diamond-chrome can plate prehardened, heat-treated or nitrided steel and other base materials such as aluminum, beryllium-copper, brass and stainless steel. Recommended uses include cores, cavities, slides, ejector sleeves, and rotating and unscrewing cores. Its anti-galling properties are advantageous on moving cores and slides.Diamond-chrome also is very strippable and has no adverse effect on the base material, saving time and money when maintenance is needed. TiN is strippable as well, but it can take up to several days to remove with a peroxide-based solution. Diamond-chrome can be stripped in minutes using reverse electrolysis in a caustic solution.In addition, diamond-chrome can be deposited at any controlled thickness from 20 millionths of an inch to 0.001 in. TiN is generally only applied in thin deposits of a few millionths of an inch. Diamond-chrome can coat complex details, while TiN has very limited coverage of complex details. While TiN is very lubricious, with a coefficient of friction (COF) of 0.4 (against steel), diamond-chrome has a COF of0.15—nearly three times more lubricious.Nickel-Boron NitrideWhen it comes to molders’ needs for a specialty coating that offers exce llent release properties and high resistance to wear, heat, and corrosion, an electrolessnickel-phosphorus matrix containing boron nitride particles should be considered.It has a very low COF (0.05 against steel) and an RC hardness of 54, which can be increased to 67 RC after heat treating—a unique characteristic. Nickel-boron nitride can be applied to any substrate at only 185oF and can be easily stripped without compromising the base material. Though it is approximately 20 percent more expensive than nickel-PTFE, this coating will outperform nickel-PTFE at up to1250oF, which far surpasses the 500oF maximum limit for all PTFE-based coatings.Because applying nickel-boron nitride is an autocatalytic process, it requires no anode, therefore saving time and money. In addition, it will not compromise thermal conductivity of the mold. Applications include unscrewing cores for closures, where reduced cycle times are essential.Where lubricity is needed for better release from deep ribs, zero-draft cores, textured surfaces and ―sticky‖ polymers, a nickel-PTFE composite will greatly improve part release and enhance resin flow by as much as 4 to 8 percent for shorter cycle times. COF is 0.10 against steel.It should be noted that applying pure PTFE to the mold adds high lubricity, but only a very short-term benefit. PTFE by itself has no hardness, so it won’t last. But a dispersion of 25 percent PTFE by volume in a co-deposit with nickel results in 45 RC hardness for added wear and corrosion protection.Tried and TrueDespite the new coating science, we cannot throw out the old, reliable coatings such as like hard chrome or electroless nickel just yet. There’s no question that they still have their uses.Hard ChromeFor example, hard chrome’s top advantage is that i t has a hardness of 72 Rockwell C (RC) and is applied at the low temperature of 130oF. When applied in its purest form, it allows you to achieve any SPI finish on your tooling.。
注塑模具设计技术中英文对照外文翻译文献
中英文资料对照外文翻译英文：Design and Technology of the Injection Mold1、3D solid model to replace the center layer modelThe traditional injection molding simulation software based on products of the center layer model. The user must first be thin-walled plastic products abstract into approximate plane and curved surface, the surface is called the center layer. In the center layer to generate two-dimensional planar triangular meshes, the use of these two-dimensional triangular mesh finite element method, and the final result of the analysis in the surface display. Injection product model using3D solid model, the two models are inconsistent, two modeling inevitable. But because of injection molding product shape is complex and diverse, the myriads of changes from athree-dimensional entity, abstraction of the center layer is a very difficult job, extraction process is very cumbersome and time-consuming, so the design of simulation software have fear of difficulty, it has become widely used in injection molding simulation software the bottleneck.HSCAE3D is largely accepted3D solid / surface model of the STL file format. Now the mainstream CAD/CAM system, such as UG, Pro/ENGINEER, CATIA and SolidWorks, can output high quality STL format file. That is to say, the user can use any commercial CAD/CAE systems to generate the desired products3D geometric model of the STL format file, HSCAE3D can automatically add the STL file into a finite element mesh model, through the surface matching and introduction of a new boundary conditions to ensure coordination of corresponding surface flow, based on3D solid model of analysis, and display of three-dimensional analysis results, replacing the center layer simulation technology to abstract the center layer, and then generate mesh this complicated steps, broke through system simulation application bottlenecks, greatly reducing the burden of user modeling, reduces the technical requirement of the user, the user training time from the past few weeks shorter for a fewhours. Figure 1 is based on the central layer model and surface model based on 3D solid / flow analysis simulation comparison chart.2、Finite element, finite difference, the control volume methodsInjection molding products are thin products, products in the thickness direction of size is much smaller than the other two dimensions, temperature and other physical quantities in the thickness direction of the change is very large, if the use of a simple finite element and finite difference method will cause analysis time is too long, can not meet the actual needs of mold design and manufacturing. We in the flow plane by using finite element method, the thickness direction by using finite difference method, were established and plane flow and thickness directions corresponding to the size of the grid and coupling, while the accuracy is guaranteed under the premise of the calculation speed to meet the need of engineering application, and using the control volume method is solved. The moving boundary problem in. For internal and external correspondence surface differences between products, can be divided into two parts the volume, and respectively formed the control equation, the junction of interpolation to ensure thatthe two part harmony contrast.3、Numerical analysis and artificial intelligence technologyOptimization of injection molding process parameters has been overwhelming majority of mold design staff concerns, the traditional CAE software while in computer simulation of a designated under the conditions of the injection molding conditions, but is unable to automatically optimize the technical parameters. Using CAE software personnel must be set to different process conditions were multiple CAE analysis, combined with practical experience in the program were compared between, can get satisfactory process scheme. At the same time, the parts after the CAE analysis, the system will generate a large amount of information about the project ( product, process, analyzes the results ), which often results in a variety of data form, requiring the user to have the analysis and understanding of the results of CAE analysis ability, so the traditional CAE software is a kind of passive computational tools, can provide users with intuitionistic, effective engineering conclusion, to software users demand is too high, the influence of CAE system in the larger scope of application and popularization. In view of the above, HSCAE3D software in the original CAE system based on accurate calculationfunction, the knowledge engineering technology is introduced the system development, the use of artificial intelligence is the ability of thinking and reasoning, instead of the user to complete a large number of information analysis and processing work, directly provide guiding significance for the process of conclusions and recommendations, effectively solve the CAE of the complexity of the system and the requirements of the users of the contradiction between, shortening of the CAE system and the distance between the user, the simulation software by traditional " passive" computational tools to " active" optimization system. HSCAE3D system artificial intelligence technology will be applied to the initial design, the results of the analysis of CAE interpretation and evaluation, improvement and optimization analysis of3 aspects.译文：注塑模具设计的技术1．用三维实体模型取代中心层模型传统的注塑成形仿真软件基于制品的中心层模型。
模具注射成型毕业论文中英文对照资料外文翻译文献
模具注射成型中英文对照资料外文翻译文献Injection MoldingThe basic concept of injection molding revolves around the ability of a thermoplastic material to be softened by heat and to harden when cooled .In most operations ,granular material (the plastic resin) is fed into one end of the cylinder (usually through a feeding device known as a hopper ),heated, and softened(plasticized or plasticated),forced out the other end of the cylinder,while it is still in the form of a melt,through a nozzle into a relatively cool mold held closed under pressure.Here,the melt cools and hardens until fully set-up.The mold is then opened,the piece ejected,and the sequence repeated.Thus,the significant elements of an injection molding machine become :1)the way in which the melt is plasticized (softened) and forced into the mold (called the injection unit);2)the system for opening the mold and closing it under pressure (called the clamping unit);3)the type of mold used;4)the machine controls.The part of an injection-molding machine,which converts a plastic material from a sold phase to homogeneous seni-liguid phase by raising its temperature .This unit maintains the material at a present temperature and force it through the injection unit nozzle into a mold .The plunger is a combination of the injection and plasticizing device in which a heating chamber is mounted between the plunger and mold. This chamber heats the plastic material by conduction .The plunger,on each storke; pushes unmelted plastic material into the chamber ,which in turn forces plastic melt at the front of the chamber out through the nozzleThe part of an injection molding machine in which the mold is mounted,and which provides the motion and force to open and close the mold and to hold the mold close with force during injection .This unit can also provide other features necessary for the effective functioning of the molding operation .Moving plate is the member of the clamping unit,which is moved toward a stationary member.the moving section of the mold is bolted to this moving plate .This member usually includes the ejector holes and moldmounting pattern of blot holes or “T”slots .Stationary plate is the fixed member of the clamping unit on which the stationary section of the mold is bolted .Thismember usually includes a mold-mounting pattern of boles or “T” slots.Tie rods are member of the clamping force actuating mechanism that serve as the tension member of the clamp whenit is holding the mold closed.They also serve as a gutde member for the movable plate .Ejector is a provision in the clamping unit that actuates a mechanism within the mold to eject the molded part(s) from the mold .The ejection actuating force may be applied hydraulically or pneumatically by a cylinder(s) attached to the moving plate ,or mechanically by the opening storke of the moving plate.Methods of melting and injecting the plastic differ from one machine to another and are constantly being improred .couventional machines use a cylinder and piston to do both jobs .This method simplifies machine construction but makes control of injection temperatures and pressures an inherently difficult problem .Other machines use a plastcating extruder to melt the plastic and piston to inject it while some hare been designed to use a screw for both jobs :Nowadays,sixty percent of the machines use a reciprocating screw,35% a plunger (concentrated in the smaller machine size),and 5%a screw pot. Many of the problems connected with in jection molding arises because the densities of polymers change so markedly withtemperature and pressure.Athigh temperatures,the density of a polymer is considerably cower than at room temperature,provided the pressure is the same.Therefore,if modls were filled at atmospheric pressure, “shrinkage”would make the molding deviate form the shape of the mold.To compensate for this poor effect, molds are filled at high pressure.The pressure compresses the polymer and allows more materials to flow into the mold,shrinkage is reduced and better quality moldings are produced.Cludes a mold-mounting pattern of bolt holes or “T”slots.Tie rods are members of the clamping force actuating machanism that serve as the tension members of clamp when it is holding the mold closed.Ejector is a provision in the claming unit that actuates a mechanism within the mold to eject themolded part(s) form the mold.The ejection actuating force may be applied hydraulically or pneumatically by a cylinder(s) attached to the moving plate,or mechanically by the opening stroke of the moving plate.The function of a mold is twofold :imparting the desired shape to the plasticized polymer and cooling the injection molded part.It is basically made up of two sets of components :the cavities and cores and the base in which the cavities and cores are mounted. The mold ,which contains one or morecavities,consists of two basic parts :(1) a stationary molds half one the side where the plastic is injected,(2)Amoving half on the closing or ejector side of the machine. The separation between the two mold halves is called the parting line.In some cases the cavity is partly in the stationary and partly in the moving section.The size and weight of the molded parts limit the number of cavities in the mold and also determine the machinery capacity required.The mold components and their functions are as following :(1)Mold Base-Hold cavity(cavities) in fixed ,correctposition relative to machine nozzle .(2)Guide Pins-Maintain Proper alignment of entry into moldintrior .(3)Sprue Bushing(sprue)-Provide means of entry into moldinterior .(4)Runners-Conrey molten plastic from sprue to cavities .(5)Gates-Control flow into cavities.(6)Cavity(female) and Force(male)-Contorl the size,shapeand surface of mold article.(7)Water Channels-Control the temperature of mold surfacesto chill plastic to rigid state.(8)Side (actuated by came,gears or hydrauliccylinders)-Form side holes,slots,undercuts and threaded sections.(9)Vent-Allow the escape of trapped air and gas.(10)Ejector Mechanism (pins,blades,stripper plate)-Ejectrigid molded article form cavity or force.(11)Ejector Return Pins-Return ejector pins to retractedposition as mold closes for next cycle.The distance between the outer cavities and the primary sprue must not be so long that the molten plastic loses too much heat in the runner to fill the outer cavities properly.The cavities should be so arranged around the primary sprue that each receives its full and equal share of the total pressure available,through its own runner system(or the so-called balanced runner system).The requires the shortest possible distance between cavities and primary sprue,equal runner and gate dimension,and uniform colling.注射成型注射成型的基本概念是使热塑性材料在受热时熔融，冷却时硬化，在大部分加工中，粒状材料（即塑料树脂）从料筒的一端（通常通过一个叫做“料斗”的进料装置）送进，受热并熔融（即塑化或增塑），然后当材料还是溶体时，通过一个喷嘴从料筒的另一端挤到一个相对较冷的压和封闭的模子里。
塑料模具毕业外文文献翻译、塑料制品的CADCAE集成的注塑模具设计系统外文翻译、中英文翻译
A CAD/CAE-integrated injection mold design system for plastic productsAbstract Mold design is a knowledge-intensive process. This paper describes a knowledge-based oriented, parametric, modular and feature-based integrated computer-aided design/computer-aided engineering (CAD/CAE) system for mold design. Development of CAx systems for numerical simulation of plastic injection molding and mold design has opened new possibilities of product analysis during the mold design. The proposed system integrates Pro/ENGINEER system with the specially developed module for the calculation of injection molding parameters, mold design, and selection of mold elements. The system interface uses parametric and CAD/CAE feature-based database to streamline the process of design, editing, and reviewing. Also presented are general structure and part of output results from the proposed CAD/ CAE-integrated injection mold design system.Keywords Mold design . Numerical simulation . CAD . CAE1 IntroductionInjection molding process is the most common molding process for making plastic parts. Generally, plastic injection molding design includes plastic product design, mold design, and injection molding process design, all of which contribute to the quality of the molded product as well as production efficiency [1]. This is process involving many design parameters that need to be considered in a concurrent manner. Mold design for plastic injection molding aided by computers has been focused by a number of authors worldwide for a long period. Various authors have developed program systems which help engineers to design part, mold, and selection parameters of injection molding. During the last decade, many authors have developed computer-aided design/computer-aided engineering (CAD/CAE) mold design systems for plastic injection molding. Jong et al. [2] developed a collaborative integrated design system for concurrent mold design within the CAD mold base on the web, using Pro/E. Low et al. [3] developed an application for standardization of initial design of plastic injection molds. The system enables choice and management of mold base of standard mold plates, but does not provide mold and injection molding calculations. The authors proposed a methodology of standardizing the cavity layout design system for plastic injection mold such that only standard cavity layouts are used. When standard layouts are used, their layout configurations can be easilystored in a database. Lin at al. [4, 5] describe a structural design system for 3D drawing mold based on functional features using a minimum set of initial information. In addition, it is also applicable to assign the functional features flexibly before accomplishing the design of a solid model for the main parts of a drawing mold. This design system includes modules for selection and calculation of mold components. It uses Pro/E modules Pro/Program and Pro/Toolkit, and consists of modules for mold selection, modification and design. Deng et al. [6, 7] analyzed development of the CAD/CAE integration. The authors also analyzed systems and problems of integration between CAD and CAE systems for numerical simulation of injection molding and mold design. Authors propose a feature ontology consisting of a number of CAD/CAE features. This feature represents not only the geometric information of plastic part, but also the design intent is oriented towards analysis. Part features contain the overall product information of a plastic part, wall features, development features (such as chamfer, ribs, boss, hole, etc.), treatment features which contain analysis-related design information and sub wall developed features. Wall and development features are so called “component features〞. God ec et al. [8, 9] developed a CAE system for mold design and injection molding parameters calculations. The system is based on morphology matrix and decision diagrams. The system is used for thermal, rheological and mechanical calculation, and material base management,Fig. 1 General structure of integrated injection mold design system for plastic productsbut no integration with commercial CAx software is provided. Huang et al. [10] developed a mold-base design system for injection molding. The database they used was parametric and feature-based oriented. The system used Pro/E for modeling database components. Kong et al. [11]developed a parametric 3D plastic injection mold design system integrated with solid works. Other knowledge-based systems, such as IMOLD, ESMOLD, IKMOULD, and IKBMOULD, have been developed for injection mold design. IMOLD divides mold design into four major steps; parting surface design, impression design, runner system design, and mold-base design. The software uses a knowledge-based CAD system to provide an interactive environment, assist designers in the rapid completion of mold design, and promote the standardization of the mold design process. IKB-MOULD application consists of databases and knowledge bases for mold manufacturing. Lou et al. [12] developed an integrated knowledge-based system for mold base design. The system has module for impression calculation, dimension calculation, calculation of the number of mold plates and selection of injection machine. The system uses Pro/ Mold Base library. This paper describes KBS and key technologies, such as product modeling, the frame-rule method, CBS, and the neural networks. A multilayer neural network has been trained by back propagation BP. This neural network adopts length, width, height and the number of parts in the mold as input and nine parameters (length, width, and height of up and down set-in, mold bases side thickness, bottom thickness of the core, and cavity plates) as output. Mok et al. [13, 14] developed an intelligent collaborative KBS for injection molds. Mok at el. [15] has developed an effective reuse and retrieval system that can register modeled standard parts using a simple graphical user interface even though designers may not know the rules of registration for a database. The mold design system was developed using an Open API and commercial CAD/computer aided manufacturing (CAM)/CAE solution. The system was applied to standardize mold bases and mold parts in Hyundai Heavy Industry. This system adopted the method of design editing, which implements the master model using features. The developed system provides methods whereby designers can register the master model, which is defined as a function of 3D CAD, as standard parts and effectively reuse standard parts even though they do not recognize the rules of the database.Todic et al. [16] developed a software solution for automated process planning for manufacturing of plastic injection molds. This CAD/CAPP/CAM system does not provide CAE calculation of parameters of injection molding and mold design. Maican et al. [17] used CAE for mechanical, thermal, and rheological calculations. They analyzed physical, mechanical, and thermal properties of plastic materials. They defined the critical parameters of loaded part. Nardinet al. [18] tried to develop the system which would suit all the needs of the injection molding for selection of the part–mold–technology system. The simulation results consist of geometrical and manufacturing data. On the basis of the simulation results, part designers can optimize part geometry, while mold designers can optimize the running and the cooling system of the mold. The authors developed a program which helps the programmers of the injection molding machine to transfer simulation data directly to the machine. Zhou et al. [1] developed a virtual injection molding system based on numerical simulation. Ma et al. [19] developed standard component library for plastic injection mold design using an object-oriented approach. This is an objector iented, library model for defining mechanical components parametrically. They developed an object-oriented mold component library model for incorporating different geometric topologies and non-geometric information. Over the years, many researchers have attempted to automate a wholeFig. 2 Structure of module for numerical simulation of injection molding processFig. 3 Forms to define the mold geometrymold design process using various knowledge-based engineering (KBE) approaches, such as rule-based reasoning (RBR), and case base (CBR) and parametric design template (PDT). Chan at al. [20] developed a 3D CAD knowledge-based assisted injection mold design system (IKB mold). In their research, design rules and expert knowledge of mold design were obtained from experienced mold designers and handbooks through various traditional knowledge acquisition processes. The traditional KBE approaches, such as RBR, CBR, and simple PDT have been successfully applied to mold cavity and runner layout design automation of the one product mold. Ye et al. [21] proposed a feature-based and object-oriented hierarchical representation and simplified symbolic geometry approach for automation mold assembly modeling. The previously mentioned analysis of various systems shows that authors used different ways to solve the problems of mold design by reducing it to mold configureator (selector). They used CAD/CAE integration for creating precision rules for mold-base selection. Many authors used CAE system for numerical simulation of injection molding to define parameters of injection molding. Several also developed original CAE modules for mold and injection molding process calculation. However, common to all previously mentioned systems is the lack of module for calculation of mold and injection molding parameters which would allow integration with the results of numerical simulation. This leads to conclusion that there is a need to create a software system which integrates parameters of injection molding with the result obtained by numericalFig. 4 Forms to determine the distance between the cooling channels and mold cavityFig. 5 Mold-base selector formssimulation of injection molding, mold calculation, and selection. All this would be integrated into CAD/CAE-integrated injection mold design system for plastic products.2 Structure of integrated CAD/CAE systemAs is well known, various computational approaches for supporting mold design systems of various authors use design automation techniques such as KBE (RBR, CBR, PDT) or design optimisation techniques such as traditional (NLP,LP, BB, GBA, IR, HR) or meta heuristic search such as (TS, SA, GA) and other special techniques such as (SPA, AR, ED).The developed interactive software system makes possible to perform: 3D modeling of the parts, analysis of part design and simulation model design, numerical simulation of injection molding, and mold design with required calculations.The system consists of four basic modules:& Module for CAD modeling of the part& Module for numerical simulation of injection molding processFig. 6 Form for mechanical mold calculation& Module for calculation of parameters of injection molding and mold design calculation and selection& Module for mold modeling (core and cavity design and design all residual mold components) The general structure of integrated injection mold design system for plastic products is shown in Fig. 1.2.1 Module for CAD modeling of the part (module I)The module for CAD modeling of the part is the first module within the integrated CAD/CAE system. This module is used for generating CAD model of the plastic product and appropriate simulation model. The result of this module is solid model of plastic part with all necessary geometrical and precision specifications. Precision specifications are: project name, number, feature ID, feature name, position of base point, code number of simulation annealing, trade material name, material grade, part tolerance, machine specification (name, clamping force, maximal pressure, dimensions of work piece), and number of cavity. If geometrical and precision specification is specified (given) with product model, the same are used as input to the nextmodule, while this module is used only to generate the simulation model.2.2 Module for numerical simulation of injection molding process (module II)Module II is used for numerical simulation of injection molding process. User implements an iterative simulation process for determining the mold ability parameters of injection molding and simulation model specification. The structure of this module is shown in Fig. 2.After a product model is imported and a polymer is selected from the plastic material database, user selects the best location for gating subsystem. The database contains rheological, thermal, and mechanical properties of plastic materials. User defines parameters of injection molding and picks the location for the gating subsystem. Further analyses are carried out: the plastic flow, fill time, injection pressure, pressure drop, flow front temperature, presence of weld line, presence of air traps, cooling quality, etc.The module offers four different types of mold flow analysis. Each analysis is aimed at solving specific problems:& Part analysis—This analysis is used to test a known gate location, material, and part geometry to verify that a part will have acceptable processing conditions.& Gate analysis—This analysis tests multiple gate locations and compares the analysis outputs to determine the optimal gate location.& Sink mark analysis—This analysis detects sink mark locations and depths to resolve cosmetic problems before the mold is built eliminating quality disputes that could arise between the molder and the customer.The most important parameters are the following: [22]& Part thickness& Flow length& Radius and drafts,& Thickness transitions& Part material& Location of gates& Number of gates& Mold temperature& Melt temperature& Injection pressure& Maximal injection molding machine pressureIn addition to the previously mentioned parameters of injection molding, the module shows following simulation results: welding line position, distribution of air traps, the distribution of injection molding pressure, shear stressFig. 7 Segment of the mechanical calculation algorithmdistribution, temperature distribution on the surface of the simulation model, the quality of filling of a simulation model, the quality of a simulation model from the standpoint of cooling, and time of injection molding [22, 23]. A part of output results from this module are the input data for thenext module. These output results are: material grade and material supplier, modulus of elasticity in the flow direction, modulus of elasticity transverse direction, injection pressure, ejection temperature, mold temperature, melting temperature, highest melting temperature thermoplastic, thermoplastic density in liquid and solid state, and maximum pressure of injection molding machine. During implementation of iterative SA procedure, user defines the moldability simulation model and the parameters of injection molding. All results are represented by different colors in the regions of the simulation model.2.3 Module for calculation of parameters of injection molding and mold design calculation and selection (module III)This module is used for analytical calculations, mold sizing, and its selection. Two of the more forms for determining the dimensions of core and cavity mold plates are shown in Fig. 3.Based on the dimensions of the simulation model and clamping force (Fig. 3) user selects the mold material and system calculates the width and length of core and cavity plates. Wall thickness between the mold cavity to the cooling channel can be calculated with the following three criteria: criterion allowable shear stress, allowable bending stress criterion, and the criterion of allowable angle isotherms are shown in Fig. 4 [22, 24]. The system adopts the maximum value of comparing the values of wall thickness calculated by previously mentioned criteria.Fig. 8 Forms for standard mold plates selectionFig. 9 Forms for mold plate model generationBased on the geometry of the simulation model, user select shape and mold type. Forms for the selection mold shape, type, and subsystems are shown in Fig. 5. Once these steps are completed, user implements the thermal, rheological, and mechanical calculation of mold specifications. An example of one of the several forms for mechanical mold calculation is shown in Fig. 6.Segment of the algorithm of mechanical calculations is shown in Fig. 7.f max maximal flexure of cavity platef dop allowed displacement of cavity plateε elastic deformationαmin minimal value of shrinkage factorE k modulus of elasticity of cavity plateG shear modulusS k wall thickness distance measuring between cavity and waterlined KT cooling channel diameterAfter the thermal, rheological, and mechanical calculations, user selects mold plates from the mold base. Form for the selection of standard mold plates is shown in Fig. 8. The system calculates the value of thickness of risers, fixed, and movable mold plates (Fig. 8). Based on the calculated dimensions, the system automatically adopts the first major standard value for the thickness of risers, movable, and fixed mold plate. Calculation of the thickness and the adoption of standard values are presented in the form as shown in Fig. 8.The interactive system recommends the required mold plates. The module loads dimensions from the database and generates a solid model of the plate. After the plate selection, the plate is automatically dimensioned, material plate isFig. 10 Structure of module IVassigned, and 3D model and 2D technical drawing are generated on demand. Dimensions of mold component (e.g., fixed plate) are shown in the form for mold plate mode generation, as shown inThe system loads the plate size required from the mold base. In this way, load up any other necessary standard mold plates that make up the mold subassembly. Subassembly mold model made up of instance plates are shown in Fig. 10Then get loaded other components of subsystems as shown in Fig. 5. Subsystem for selection other components include bolts and washers. The way of components selection are based on a production rules by authors and by company “D-M-E〞[25, 26].2.4 Module for mold modeling (core and cavity design and design all residual mold components; module IV)This module is used for CAD modeling of the mold (core and cavity design). This module uses additional software tools for automation creating core and cavity from simulation (reference) model including shrinkage factor of plastics material and automation splitting mold volumes of the fixed and movable plates. The structure of this module is shown in Fig. 11.Additional capability of this module consists of software tools for:& Applying a shrinkage that corresponds to design plastic part, geometry, and molding conditions, which are computed in module for numerical simulation& Make conceptual CAD model for nonstandard plates and mold components& Design impression, inserts, sand cores, sliders and other components that define a shape of molded part& Populate a mold assembly with standard components such as new developed mold base which consists of DME mold base and mold base of enterprises which use this system, and CAD modeling ejector pins, screws, and other components creating corresponding clearance holes& Create runners and waterlines, which dimensions was calculated in module for calculating of parameters of injection molding and mold design calculation and selection& Check interference of components during mold opening, and check the draft surfacesAfter applied dimensions and selection mold components, user loads 3D model of the fixed (core) and movable (cavity) plate. Geometry mold specifications, calculated in the previous module, are automatically integrated into this module, allowing it to generate the final mold assembly. Output from this module receives the complete mold model of the assembly as shown in Fig. 15. Thismodule allowsFig. 11 Subassembly model of moldFig. 12 CAD model of the test Productmodeling of nonstandard and standard mold components that are not contained in the mold base.3 Case studyThe complete theoretical framework of the CAD/CAE-integrated injection mold design system for plastic products was presented in the previous sections. In order to complete this review, the system was entirely tested on a real case study. The system was tested on few examples of similar plastic parts. Based on the general structure of the model of integrated CAD/CAE design system shown in Fig. 1, the authors tested the system on some concrete examples. One of the examples used for verification of the test model of the plastic part is shown in Fig. 12.The module for the numerical simulation of injection molding process defines the optimal location for setting gating subsystem. Dark blue regions indicate the optimal position for setting gating subsystem as shown in Fig. 13.Based on dimensions, shape, material of the case study product (Fig. 11), optimal gating subsystem location (Fig. 13), and injection molding parameters (Table 1), the simulation model shown in Fig. 14 was generated.One of the rules for defining simulation model gate for numerical simulation:IF (tunnel, plastic material, mass) THEN prediction dimension (upper tunnel, length, diameter1, diameter2, radius, angle, etc.)Part of the output results from module II, which are used in module III are shown in Table 1.Fig. 13 Optimal gating subsystem location in the partTable 1 Part of the output results from the module for the numerical simulation of injection molding processMaterial grade and material supplier Acrylonitrile butadiene styrene 780(ABS 780),Kumho Chemicals Inc.Max injection pressure 100 MPaMold temperature 60°C ili 40Melt Temperature 230°CInjection Time 0,39 s 0,2 sInjection Pressure 27,93 MPaRecommended ejection temperature 79°CModulus of elasticity, flow direction for ABS 780 2,600 MPaModulus of elasticity, transverse direction for ABS 780 2,600 MPaPoision ratio in all directions for ABS 780 0.38Shear modulus for ABS 780 942 MPaDensity in liquid state 0.94032 g/cm3Density in solid state 1.047 g/cm3In module III, the system calculates clamping force F=27.9 kN (Fig. 3), cooling channel diameter d KT=6 mm, cooling channel length lKT090 mm (Fig. 4). Given the shape and dimensions of the simulation model, square shape of mold with normal performance was selected as shown in Fig. 5. Selected mold assembly standard series: 1,616, length and width of mold housing 156×156 mm as shown in Fig. 8. In the segment of calculation shown in Fig. 8, mold design system panel recommends the following mold plates:& Top clamping plate N03-1616-20& Bottom clamping plate N04-1616-20& Fixed mold plate (core plate) N10A-1616-36& Movable plate (cavity plate) N10B-1616-36& Support plate N20-1616-26& Risers N30-1616-46& Ejector retainer plate N40-1616-10& Ejector plate N50-1616-12After finishing the fixed and movable mold plates from the standpoint of CAD modeling core and cavity plates, cooling channel, followed by manual selection of other mold standard components such as sprue bush, locating ring, guide pins, guide bush, leading bushing guide, spacer plates, screws (M4×10, M10×100, M10×30, M6×16, M10×30, etc.) and modeling nonstandard mold components (if any) ejector pins, ejector holes, inserts etc. A complete model of the mold assembly with tested simulation model is shown in Fig. 15.Fig. 14 Simulation model of plastic partFig. 15 Model of the mold assembly with tested simulation model4 ConclusionThe objective of this research was to develop a CAD/CAE integrated system for mold design which is based on Pro/ ENGINEER system and uses specially designed and developed modules for mold design. This paper presents a software solution for multiple cavity mold of identical molding parts, the so-called one product mold. The system is dedicated to design of normal types of molds for products whose length and width are substantially greater than product height, i.e., the system is customized for special requirements of mold manufacturers. The proposed system allows full control over CAD/CAE feature parameters which enables convenient and rapid mold modification. The described CAD/CAE modules are feature-based, parametric, based on solid models, and object oriented. The module for numerical simulation of injection molding allows the determination selection of injection molding parameters. The module for calculation of parameters of injection molding process and mold design calculation and selection improves design Fig. 15 Model of the mold assembly with tested simulation model faster, reduces mold design errors, and provides geometric and precision information necessary for complete mold design. The knowledge base of the system can be accessed by mold designers through interactive modules so that their own intelligence and experience can also be incorporated into the total mold design. Manufacture of the part confirms that the developed CAD/CAE system provides correct results and proves to be a confident software tool.Future research will be directed towards three main goals. The first is to develop a system for automation of family mold design. Another line of research is the integration with CAPP system for plastic injection molds manufacturing developed at the Faculty of Technical Sciences. Finally, following current trends in this area, a collaborative system using web technologies and blackboard architecture shall be designed and implemented.塑料制品的CAD / CAE集成的注塑模具设计系统摘要：模具设计是一个知识密集的过程。
注射注塑模具外文翻译外文文献翻译、中英文翻译、外文翻译
外文资料翻译系部：专业：姓名：学号：外文出处：dvanced English literacy course（用外文写）附件：指导老师评语签名：年月日第一篇译文（中文）2.3注射模2.3.1注射模塑注塑主要用于热塑性制件的生产，它也是最古老的塑料成型方式之一。
目前，注塑占所有塑料树脂消费的30%。
典型的注塑产品主要有杯子器具、容器、机架、工具手柄、旋钮（球形捏手）、电器和通讯部件（如电话接收器），玩具和铅管制造装置。
聚合物熔体因其较高的分子质量而具有很高的粘性；它们不能像金属一样在重力流的作用下直接被倒入模具中，而是需要在高压的作用下强行注入模具中。
因此当一个金属铸件的机械性能主要由模壁热传递的速率决定，这决定了最终铸件的晶粒度和纤维取向，也决定了注塑时熔体注入时的高压产生强大的剪切力是物料中分子取向的主要决定力量。
由此所知，成品的机械性能主要受注射条件和在模具中的冷却条件影响。
注塑已经被应用于热塑性塑料和热固性塑料、泡沫部分，而且也已经被改良用于生产反应注塑过程，在此过程中，一个热固树脂系统的两个组成部分在模具中同时被注射填充，然后迅速聚合。
然而大多数注塑被用热塑性塑料上，接下来的讨论就集中在这样的模具上。
典型的注塑周期或流程包括五个阶段（见图2-1）：（1）注射或模具填充；（2）填充或压紧；（3）定型；（4）冷却；（5）零件顶出。
图2-1 注塑流程塑料芯块（或粉末）被装入进料斗，穿过一条在注射料筒中通过旋转螺杆的作用下塑料芯块（或粉末）被向前推进的通道。
螺杆的旋转迫使这些芯块在高压下对抗使它们受热融化的料筒加热壁。
加热温度在265至500华氏度之间。
随着压力增强，旋转螺杆被推向后压直到积累了足够的塑料能够发射。
注射活塞迫使熔融塑料从料筒，通过喷嘴、浇口和流道系统，最后进入模具型腔。
在注塑过程中，模具型腔被完全充满。
当塑料接触冰冷的模具表面，便迅速固化形成表层。
由于型芯还处于熔融状态，塑料流经型芯来完成模具的填充。
铸造模具外文文献翻译、中英文翻译
外文资料翻译资料来源：书籍文章名：Chapter 4 Casting Dies书刊名：《English for Die & Mould Design and Manufacturing》作者：刘建雄王家惠廖丕博主编出版社：北京大学出版社，2002章节：Chapter 4 Casting Dies页码：P61~P96文章译名：铸造模具Chapter 4 Forging Die4.1IntroductionForging is a process in which the workpiece is shaped by compressive forces applied through various dies and tools. It is one of the oldest metalworking operations, dating back at least to 4000 B.C.——perhaps as far back as 8000 B.C. Forging was first used to make jewelry, coins, and various implements by hammering metal with tools made of stone.Simple forging operations can be performed with a heavy hand hammer and an anvil, as was traditionally done by blacksmiths. Most forgings, however, require a set of dies and such equipment as a press or a forging hammer.Typical forged products are bolts and rivets, connecting rods, shafts for turbines, gears, hand tools, and structural components for machinery, aircraft, railroads, and a variety of other transportation equipment.Metal flow and grain structure can be controlled, so forged parts have good strength and toughness; they can be used reliably for highly stressed and critical applications (Fig. 4-1). Forg- ing may be done at room temperature (cold forging) or at elevated temperatures (warm or hot forging, depending on the temperature).(a)(b) (c)Fig. 4-1 A part made by three different processes, showing grain flow(a)casting (b) machining (c) forgingBecause of the higher strength of the material, cold forging requires greater forces, and the workpiece materials must have sufficient ductility at room temperature. Cold-forged parts have good surface finish and dimensional accuracy. Hot forging requires smaller forces,but produces dimensional accuracy and surface finish that are not as good. Forgings generall yrequire additional finishing operations, such as heat treatin g, to modify properties, and then machining to obtain accurate finished dimens ions. These operations can be minimized by precision forging, which is an imp ortant example of the4.2Open-Die ForgingOpen-die forging is the simplest forging process. Although most open-die forging generally weighs 15 kg~500 kg, forging as heavy as 300 tons have been made. Sizes may range from very small parts up to shafts some 23 m long (in the case of ship propellers).The open-die forging process can be depicted by a solid workpiece placed between two flat dies and reduced in height by compressing it (Fig. 4-2). This process is also called upsetting or flat-die forging. The die surfaces in open-die forging may have simple cavities, to produce relatively simple forgings. The deformation of the workpiece under ideal conditions is shown in Fig. 4-2 (b). Because constancy of volume is maintained, any reduction in height increases the diameter of the forged part.Note that, in Fig. 4-2 (b), the workpiece is deformed uniformly. In actual operations, the part develops a barrel shape (Fig. 4-2 (c)); this deformation is also known as pancaking. Barreling is caused primarily by frictional forces at the die-workpiece interfaces that oppose theoutward flow of the materials at these interfaces. Barreling can be minimized if an effective lubricant is used.WorkpieceDie(a) Die (b) (c) Friction forceBarrelingFig. 4-2 (a) Solid cylindrical billet upset between two flat dies (b) Uniformdeformation of the billet without friction (c) Deformation with frictionBarreling can also occur in upsetting hot workpieces between cold dies. The material at and near the interfaces cools rapidly, while the rest of the workpiece remains relatively hot. Thus, the material at the ends of the workpiece has higher resistance to deformation than the material at its center. Consequently, the central portion of the workpiece expands laterally to a greater extent than do its ends. Barreling from thermal effects can be reduced or eliminated by using heated dies; thermal barriers such as glass cloth at the die-workpiece interfaces are also used.5Cogging, also called drawing out, is basically an open-die forging operation in which the thickness of a bar is reduced by successive forging steps at specific intervals (Fig. 4-3). Because the contact area per stroke is small, a long section of a bar can be reduced in thickness without requiring large forces or machinery. Blacksmiths perform such operations with a hammer and an anvil using hot pieces of metal; iron fences of various designs are often made by this process.4.3 Impression-Die and Closed-Die ForgingIn impression-die forging, the workpiece acquires the shape of the die cavities (impressions) while being forged between two shaped dies (Fig. 4-4). Note that some of the material flows outward and forms a flash. The flash has a significant role in flow of material in impression-die forging: The thin flash cools rapidly, and, because of its frictional resistance, it subjects the material in the die cavity to high pressures, thereby encouraging the filling of the die cavity.FlashFig. 4-4 Stages in impression-die forging of a solid round billetThe blank to be forged is prepared by such means as (a) cutting or cropping from an extruded or drawn bar stock, (b) a preform in operations such as powder metallurgy, (c) casting, or (d) a preform blank in a prior forging operation. The blank is placed on the lower die and, as the upper die begins to descend, the blank’s shape gradually changes, as is shown for the forging of a connecting rod in Fig. 4-5 (a).DieBlank (bar stock)EdgingBlockingFinishingTrimming(a) (b)(c)WorkpieceDieFig. 4-5 (a) Stages in forging a connecting rod for an internal combustion engine (b) Fullering(b)Edging operations to distribute the material when preshaping the blank for forgingPreforming processes, such as fullering and edging (Figs. 4-5 (b) and (c)), are used to distribute the material into various regions of the blank, much as they are in shaping dough to make pastry. In fullering, material is distributed away from an area; in edging, it is gathered into a localized area. The part is then formed into the rough shape of a connecting rod by a process called blocking, using blocker dies. The final operation is the finishing of the forging in impression dies that give the forging its final shape. The flash is removed usually by a trimming operation (Fig. 4-6).The examples shown in Figs. 4-4 and 4-5 (a) are also referred to as closed-die forgings. However, in true closed-die or flashless forging, flash does not form and the workpiece com-pletely fills the die cavity (right side of Fig. 4-7 (b)). Accurate control of the volume of material and proper die design are essential in order to obtain a closed-die forging of the desired dimensions and tolerances. Undersize blanks prevent the complete filling of the die cavity; conversely, oversize blanks generate excessive pressures and may cause dies to fail prematurely or to jam.Before AfterPunchFlashTrimming dieSlugStationary punchFig. 4-6 Trimming flash from a forged partForging with flashFlashless forgingUpper die UpperpunchForgingBilletFlashLowerdieDieLower punch(a)Start of stroke (b) End of strokeFig. 4-7 Comparison of closed-die forging to precision or flashless forging of a cylindrical billet4.3.1Precision ForgingFor economic reasons the trend in forging operations today is toward greater precision, which reduces the number of additional finishing operations. Operations in which the part formed are close to the final dimensions of the desired component are known as near-net-shape or net-shape forging. In such a process, there is little excess material on the forged part, and it is subsequently removed (generally by trimming or grinding).In precision forging, special dies produce parts having greater accuracies than those from impression-die forging and requiring much less machining. The process requires higher-capacity equipment, because of the greater forces required to obtain fine details on the parts. Because of the relatively low forging loads and temperatures that they require, aluminum and magnesium alloys are particularly suitable for precision forging; also, little die wear takes place and the surface finish is good. Steels and titanium can also be precision-forged. Typical precision-forged products are gears, connecting rods, housings, and turbine blades.Precision forging requires special and more complex dies, precise control of the billet’s volume and shape, accurate positioning of the billet in the die cavity, and hence higher investment. However, less material is wasted, and much less subsequent machining is required, because the part is closer to the final desired shape. Thus, the choice between conventional forging and precision forging requires an economic analysis, particularly in regard to the production volume.4.3.2CoiningCoining essentially is a closed-die forging process typically used in minting coins, medallions, and jewelry (Fig. 4-8 (a), (b)). The slug is coined in a completely closed die cavity. In order to produce fine details the pressures required can be as high as five or six times the strength of the material, note, for example, the detail on newly minted coins. On some parts, several coining operations may be required. Lubricants cannot be applied in coining, because they can become entrapped in the die cavities and, being incompressible, prevent the full reproduction of die-surface details.The coining process is also used with forgings and with other products, to improve surface finish and to impart the desired dimensional accuracy. This process, called sizing, involves high pressures, with little change in part shape during sizing. Marking of parts with letters and numbers can be done rapidly by a process similar to coining.Retaining ringDie holder(a) Upper dieDie holderWorkpieceLower dieWorkpieceDie with depressions(b)Flat dieFig. 4-8 (a) Schematic illustration ofthe coining process (b) An exampleof a coining operation to produce animpression of the letter E on a block of metal4.4 Forging-Die DesignThe design of forging dies requires knowledge of the strength and ductility of the workpiece material, its sensitivity to deformation rate and temperature, its frictional characteristics, and the shape and complexity of the workpiece. Die distortion under high forging loads is an importantconsideration, particularly if close tolerances are required.The most important rule in die design is the fact that the part will flow in the direction of least resistance. Thus the workpiece (intermediate shape) should be shaped so that it properly fills the die cavities. An example of the intermediate shapes for a connecting rod is shown in Fig. 4-9. The importance of preforming can be appreciated by noting how a piece of dough is preshaped to make a pie crust or how ground meat is preshaped to make a hamburger.Fig. 4-9 Swaging of tubes without a mandrel4.4.1PreshapingIn a properly preshaped workpiece, the material should not flow easily into the flash, the grain flow pattern should be favorable, and excessive sliding at the workpiece-die interlaces should be minimized in order to reduce wear. Selection of shapes requires considerable experience and involves calculations of cross-sectional areas at each location in the forging.Computer-aided design techniques have been developed to expedite these calculations, as well as to predict the material-flow pattern in the die cavity and to predict the formation of defects. Because the material undergoes different degrees of deformation (and at different rates) in various regions in the die cavity, the mechanical properties depend on the particular location i n the forging.4.4.2Die Design FeaturesThe terminology for forging dies is shown in Fig. 4-10, and the significance of various features is described below. Some of these considerations are similar to those for casting. For most forgings, the parting line is usually at the largest cross-section of the part. For simple symmetrical shapes, the parting line is normally a straight line at the center of the forging, but for more complex shapes the line may not lie in a single plane. The dies are then designed in such a way that they lock during engagement, in order to avoid side thrust, balance forces, and maintaindie alignment during forging.CornerFig. 4-10 Standard terminology for various features of a typical impressionAfter sufficiently constraining lateral flow to ensure proper die filling, the flash material is allowed to flow into a gutter, so that the extra flash does not increase the forging load unnecessarily. A general guideline for flash clearance between dies is 3% of the maximum thickness of the forging. The length of the land is usually two to five times the flash thickness. Several gutter designs have been developed throughout the years.Draft angles are necessary in almost all forging dies, in order to facilitate the removal of the part from the die. Upon cooling, the forging shrinks both radially and longitudinally, so internal draft angles are made larger than external ones. Internal angles are about 7°to 10°, external angles about 3°to 5°.Selection of the proper radii for corners and fillets is important, in order to ensure smooth flow of the metal into the die cavity and to improve die life. Small radii are generally undesirable, because of their adverse effect on metal flow and their tendency to wear rapidly (as a result of stress concentration and thermal cycling). Small fillet radii also can cause fatigue cracking of the dies. As a general rule, these radii should be as large as can be permitted by the design of the forging.Instead of being made as one piece, dies may be assembled with die insets (Fig. 4-11), particularly for complex shapes; this alternative reduces the cost of making several similar dies. The inserts can be made of stronger and harder materials, and they can be changed easily in the case of wear or failure in a particular section of the die.Upper die blockInsertWorkpieceFig. 4-11 Die inserts used in dies for forging an automotive axle housingAs with the patterns used in casting, allowances are provided in forging-die design because machi ning the forging may be necessary to obtain final desired dimensions and surface finish. Machining allowance should be provided at flanges, at holes, and at mating surfaces.4.5 Forging MachinesA variety of forging machines are in use, with a range of capacities, speeds, and speed- stroke characteristics. These machines are generally classified as presses or hammers.4.5.1Presses1.Hydraulic PressesThese presses operate at constant speeds and are load limited, or load restricted. In otherwords, a press stops if the load required exceeds its capacity. Large amounts of energy can be transmitted to a workpiece by a constant load throughout a stroke, the speed of which can be controlled. Because forging in a hydraulic press takes longer than in other types of forging machines, the workpiece may cool rapidly unless the dies are heated. Compared to mechanical presses, hydraulic presses are slower and involve higher initial cost, but they require less maintenance.A hydraulic press typically consists of a frame with two or four columns, pistons, cylinders(Fig. 4-12 (a)), rams, and hydraulic pumps driven by electric motors. The main landing-gearsupport beam for the Boeing 747 aircraft is forged in a 450-MN (50,000-ton) hydraulic press,shown in Fig. 4-12 (c) (with the part in the forefront). This part is made of a titanium alloy andweighs approximately 1350 kg (1.35 tons).2.Mechanical PressesThese presses are basically of either the crank or the eccentric type (Fig. 4-12 (b)). The speedvaries from a maximum at the center of the stroke to zero at the bottom of the stroke, so they arestroke limited. The energy in a mechanical press is generated by a large flywheel powered by anelectric motor. A clutch engages the flywheel to an eccentric shaft. A connecting rod translates therotary motion into a reciprocating linear motion. A knuckle-joint mechanical press is shown in Fig.4-12 (c). Because of the linkage design, very high forces can be applied in this type of press (seealso Fig. 4-12 (a)).The force available in a mechanical press depends on the stroke position; it becomes extremely high at the bottom dead center. Thus proper setup is essential to avoid breaking the diesor equipment components. Mechanical presses have high production rates; they are easier toautomate and require less operator skill than do other types of forging machines. Press capacitieoperation is repeated until the forging is completed.Screw presses are used for various open-die and closed-die forging operations; they are particularly suitable for small production quantities and precision parts, such as turbine blades. Capacities range from 1.4 MN to 280 MN (160 tons to 31,500 tons).4.5.2HammersHammers derive their energy from the potential energy of the ram, which is converted into kinetic energy (Fig. 4-12 (e)); thus they are energy limited. Unlike hydraulic presses, they operate at high speeds, and the resulting low forming time minimizes the cooling of a hot forging. Low cooling rates allow the forging of complex shapes, particularly those with thin and deep recesses. To complete the forging, several successive blows are usually made in the same die. Hammers are available in a variety of designs; they are the most versatile and the least expensive type of forging equipment.1.Gravity Drop HammersIn the operation of this hammer, a process called drop forging, the energy is derived from the free-falling ram (the hammer shown in Fig. 4-12 (e) is known as a board hammer). The available energy of the hammer is the product of the ram’s weight and the height of its drop. Ram weighs range from 180 kg to 4500 kg, with energy capacities ranging up to 120 kJ.2.Power Drop HammersIn this hammer, the ram’s downstroke is accelerated by steam, air, o r hydraulic pressure at about 750 kPa. Ram weighs range from 225 kg to as much as 22,500 kg, with energy capacities ranging up to 1150 kJ.3.Counterblow HammersThis hammer has two rams that simultaneously approach each other horizontally or vertically to forge the part. As in open-die forging operations, the part may be rotated between blows for proper shaping of the workpiece during forging. Counterblow hammers operate at high speeds and transmit less vibration to their bases. Capacities range up to 1200 kJ.4.High-Energy-Rate MachinesIn a high-energy-rate machine, the ram is accelerated by inert gas at high pressure, and the part is forged in one blow at a very high speed. Although there are several types of these machines, various problems associated with their operation and maintenance, with die breakage,and with safety considerations have greatly limited their actual use in forging plants.4.5.3Selection of Forging MachinesSeveral considerations are important in the selection of forging machines: force or energy requirements; the size, shape and complexity of the forging; the strength of the workpiece material; and the sensitivity of the material to the rate of deformation. Additional factors include production rate, dimensional accuracy, maintenance, operating skills required, noise level, and cost.In general, presses are preferred for use with aluminum, magnesium, beryllium, bronze, and brass. Hammers are usually preferred for use with steels, titanium, copper, and refractory-metal alloys. A forging may also be made on two or more types of equipment, that is, first on a hammer, then on a hydraulic or mechanical press.(a) (b) (c) Core printsMechanical drawing of part (d) (e)Core boxesCore printsCope pattern plateCore halvespasted together(f)FlaskGateDrag pattern plateRisers SprueCope ready for sand(g) (h) (i)Cope after ramming withsand and removing pattern, sprue, and risers Drag ready for sandDrag afterremoving pattern(j)CopeDrag (k)(l)(m)Drag with core set in place ClosingpinsCope and dragassembled readyfor pouringCasting asremoved frommold; heat treatedFig. 3-9 Schematic illustration of the sequence of operations for sand castingAlmost all commercially-used metals can be sand cast. The surface finish obtained is largely a function of the materials used in making the mold. Dimensional accuracy is not as good as that of other casting processes. However, intricate shapes can be cast by this process, such as cast-iron engine blocks and very large propellers for ocean liners. Sand casting can be economical for relatively small production runs, and equipment costs are generally low.The surface of castings is important in subsequent machining operations, because machi- nability can be adversely affected if the castings are not cleaned properly and sand particles remain on the surface. If regions of the casting have not formed properly or have formedincompletely, the defects may be repaired by filling them with weld metal. Sand-mold castings generally have rough, grainy surfaces, depending on the quality of the mold and the materials used.The casting may subsequently be heat-treated to improve certain properties needed for its intended service use; these processes are particularly important for steel castings. Finishing operations may involve machining straightening, or forging with dies to obtain final dimensions.Minor surface imperfections may also be filled with a metal-filled epoxy, especially for cast-iron castings because they are difficult to weld. Inspection is an important final step and is carried out to ensure that the casting meets all design and quality control requirements.第4章锻模4.1介绍锻造是通过各种模具和工具施加的压缩力来成形工件的过程。
铸造模具外文文献翻译、中英文翻译
外文资料翻译资料来源：《模具设计与制造专业英语》文章名：Chapter 3 Casting Dies书刊名：《English for Die & Mould Design and Manufacturing》作者：刘建雄王家惠廖丕博主编出版社：北京大学出版社，2002章节：Chapter 3 Casting Dies页码：P51~P60文章译名：铸造模具Chapter 3 Casting Dies3.1CastingThe first castings were made during the period 4000~3000 B.C., using stone and metal molds for casting copper. Various casting processes have been developed over a long period of time, each with its own characteristics and applications, to meet specific engineering and service requirements. Many parts and components are made by casting, including cameras, carburetors, engine blocks, crankshafts, automotive components, agricultural and railroad equipment, pipes and plumbing fixtures, power tools, gun barrels, frying pans, and very large components for hydraulic turbines.Casting can be done in several ways. The two major ones are sand casting, in which the molds used are disposable after each cycle, and die casting, or permanent molding, in which the same metallic die is used thousands or even millions of times. Both types of molds have three common features. They both have a “plumbing” system to channel molten alloy into the mold cavity. These channels are called sprues, runners, and gates (Fig. 3-1). Molds may be modified by cores which form holes and undercuts or inserts that become an integral part of the casting. Inserts strengthen and reduce friction, and they may be more machinable than the surrounding metal. For example, a steel shaft when properly inserted into a die cavity results in an assembled aluminum step gear after the shot.After pouring or injection, the resulting castings require subsequent operations such trim-ming, inspection, grinding, and repairs to a greater or lesser extent prior to shipping. Premium-quality castings from alloys of aluminum or steel require x-ray soundness that will be acceptable by the customer.Certain special casting processes are precision-investment casting, low-pressure casting, and centrifugal casting.3.2Sand CastingThe traditional method of casting metals is in sand molds and has been used for millennia. Simply stated, sand casting consists of (a) placing a pattern having the shape of the desired casting in sand to make an imprint, (b) incorporating a gating system, (c) filling the resulting cavity with molten metal, (d) allowing the metal to cool until it solidifies, (e) breaking away the sand mold, and (f) removing the casting (Fig. 3-2). The production steps for a typical sand-casting operation are shown in Fig. 3-3.Although the origins of sand casting date to ancient times, it is still the most prevalent form of casting. In the United States alone, about 15 million tons of metal are cast by this method each year.Open riser Vent Pouring basin (cup)CopeBlind FlaskriserSprueCore(sand)SandParting lineDragMoldcavityChokeRunner GateSandFig. 3-2 Schematic illustration of a sand mold33.2.1SandsMost sand casting operations use silica sand (SiO2), which is the product of the dis- integration of rocks over extremely long periods of time. Sand is inexpensive and is suitable as mold material because of its resistance to high temperatures. There are two general types of sand: naturally bonded (bank sand) and synthetic (lake sand). Because its composition can be controlled more accurately, synthetic sand is preferred by most foundries.Several factors are important in the selection of sand for molds. Sand having fine, round grains can be closely packed and forms a smooth mold surface. Although fine-grained sand enhances mold strength, the fine grains also lower mold permeability. Good permeability of molds and cores allows gases and steam evolved during casting to escape easily.3.2.2Types of Sand MoldsSand molds are characterized by the types of sand that comprise them and by the methods used to produce them. There are three basic types of sand molds: greensand, cold-box, and no-bake molds.The most common mold material is green molding sand, which is a mixture of sand, clay, and water. The term “green” refers to the fact that the sand in the mold is moist or damp while the metal is being poured into it. Greensand molding is the least expensive method of makingmolds.In the skin-dried method, the mold surfaces are dried, either by storing the mold in air or by drying it with torches. These molds are generally used for large castings because of their higher strength.Sand molds are also oven dried (baked) prior to pouring the molten metal; they are stronger than greensand molds and impart better dimensional accuracy and surface finish to the casting. However, this method has drawbacks: distortion of the mold is greater; the castings are more susceptible to hot tearing because of the lower collapsibility of the mold; and the production rate is slower because of the drying time required.In the cold-box mold process, various organic and inorganic binders are blended into the sand to bond the grains chemically for greater strength. These molds are dimensionally more accurate than greensand molds but are more expensive.In the no-bake mold process, a synthetic liquid resin is mixed with the sand; the mixture hardens at room temperature. Because bonding of the mold in this and in thecold-box process takes place without heat, they are called cold-setting processes.The following are the major components of sand molds (Fig. 3-2):(1)The mold itself, which is supported by a flask. Two-piece molds consist of a cope on top and a drag on the bottom. The seam between them is the parting line. When more than two pieces are used, the additional parts are called cheeks.(2)A pouring basin or pouring cup, into which the molten metal is poured.(3)A sprue, through which the molten metal flows downward.(4)The runner system, which has channels that carry the molten metal from the sprue to the mold cavity. Gates are the inlets into the mold cavity.(5)Risers, which supply additional metal to the casting as it shrinks during solidification. Fig. 3-2 shows two different types of risers: a blind riser and an open riser.(6)Cores, which are inserts made from sand. They are placed in the mold to form hollow regions or otherwise define the interior surface of the casting. Cores are also used on the outside of the casting to form features such as lettering on the surface of a casting or deep external pockets.(7)Vents, which are placed in molds to carry off gases produced when the molten metal comes into contact with the sand in the mold and core. They also exhaust air from the mold cavity as the molten metal flows into the mold.3.2.3PatternsPatterns are used to mold the sand mixture into the shape of the casting. They may be made of wood, plastic, or metal. The selection of a pattern material depends on the size and shape of the casting, the dimensional accuracy, the quantity of castings required, and the molding process.Because patterns are used repeatedly to make molds, the strength and durability of the material selected for patterns must reflect thenumber of castings that the mold will produce.They may be made of a combination of materials to reduce wear in critical regions. Patterns are usually coated with a parting agent to facilitate their removal from the molds.Patterns can be designed with a variety of features to fit application and economic requirements. One-piece patterns, also called loose or solid patterns, are generally used for simpler shapes and low-quantity production. They are generally made of wood and are inexpensive. Split patterns are two-piece patterns made such that each part forms a portion of the cavity for the casting; in this way, castings with complicated shapes can be produced.Match-plate patterns are a popular type of mounted pattern in which two-piece patterns are constructed by securing each half of one or more split patterns to the opposite sides of a single plate (Fig.3-4). In such constructions, the gating system can be mounted on the drag side of the pattern. This type of pattern is used most often in conjunction with molding machines and large production runs to produce smaller castings.Cope sidePlateDrag sideFig. 3-4 A typical metal match-plate pattern used in sand castingAn important recent development is the application of rapid prototyping to moldand pattern making. In sand casting, for example, a pattern can be fabricated in arapid prototyping machine and fastened to a backing plate at a fraction of the timeand cost of machining a pattern. There are several rapid prototyping techniques withwhich these tools can be produced quickly.Pattern design is a crucial aspect of the total casting operation. The design should provide for metal shrinkage, case of removal from the sand mold by means of a taper or draft (Fig.3-5), and proper metal flow in the mold cavity.Pattern Draft angleDamageFlaskSand moldPoor GoodFig. 3-5 Taper on patterns for case of removal from the sand mold3.2.4CoresFor castings with internal cavities or passages, such as those found in an automotive engine block or a valve body, cores are utilized. Cores are placed in themold cavity before casting to form the interior surfaces of the casting and are removed from the finished part during shakeout and further processing. Like molds,cores must possess strength, permeability, ability to withstand heat, and collapsibility; therefore, cores are made of sand aggregates.The core is anchored by core prints. These are recesses that are added to the pattern to support the core and to provide vents for the escape of gases (Fig. 3-6). A common problem with cores is that for some casting requirements, as in the casewhere a recess is required, they may lack sufficient structural support in the cavity.To keep the core from shifting, metal supports (chaplets) may be used to anchor thecore in place (Fig. 3-6).ChapletCore CoreCoreprintsCavity PartinglineMoldCavity CoreprintsFig. 3-6 Examples of sand cores showing core prints and chaplets to support cores8Cores are generally made in a manner similar to that used in making molds; the majority are made with shell, no-bake, or cold-box processes. Cores are formed in core boxes, which are used in much the same way that patterns are used to form sand molds. The sand can be packed into the boxes with sweeps, or blown into the box by compressed air from core blowers. The latter have the advantages of producing uniform cores and operating at very high production rates.3.2.5Sand-Molding MachinesThe oldest known method of molding, which is still used for simple castings, is to compact the sand by hand hammering (tamping) or ramming it around the pattern. For most operations, however, the sand mixture is compacted around the pattern by molding machines (Fig.3-7). These machines eliminate arduous labor, offer high-quality casting by improving the application and distribution of forces, manipulate the mold in a carefully controlled manner, and increase production rate.Squeeze head(a)(c) Equalizing pistons Pressurized air(b)(d)DiaphragmHydraulic cylinderFig. 3-7 Various designs of squeeze heads for mold making(a)conventional flat head (b) profile head (c) equalizing squeeze pistons (d) flexible diaphragmMechanization of the molding process can be further assisted by jolting the assembly. The flask, molding sand, and pattern are first placed on a pattern plate mounted on an anvil, and then jolted upward by air pressure at rapid intervals. The inertial forces compact the sand around the pattern. Jolting produces the highest compaction at the horizontal parting line, whereas in squeezing, compaction is highest at the squeezing head (Fig. 3-7). Thus, more uniform com- paction can be obtained by combining squeezing and jolting.In vertical flaskless molding, the halves of the pattern form a vertical chamber wall against which sand is blown and compacted (Fig. 3-8). Then, the mold haves are packed horizontally, with the parting line oriented vertically and moved along a pouring conveyor. This operation is simple and eliminates the need to handle flasks, allowing for very high production rates, particularly when other aspects of the operation (such as coring and pouring) are automated.Ram forceBoxSandPatternMetal poured here(a)(b)Fig. 3-8 Vertical flaskless molding(a)sand is squeezed between two halves of the pattern(b)assembled molds pass along an assembly line for pouringSandslingers fill the flask uniformly with sand under high-pressure stream. They are used to fill large flasks and are typically operated by machine. An impeller in the machine throws sand from its blades or cups at such high speeds that the machine not only places the sand but also rams it appropriately.In impact molding, the sand is compacted by controlled explosion or instantaneous release of compressed gases. This method produces molds withuniform strength and good permeability.In vacuum molding, also known as the “V” process, the pattern is covered tightly by a thin sheet of plastic. A flask is placed over the coated pattern and is filled with dry binderless sand. A second sheet of plastic is then placed on top of the sand, and a vacuum action hardens the sand so that the pattern can be withdrawn. Both halves of the mold are made this way and assembled.During pouring, the mold remains under a vacuum but the casting cavity does not. When the metal has solidified, the vacuum is turned off and the sand falls away, releasing the casting. Vacuum molding produces castings with high-quality detail and dimensional accuracy. It is especially well suited for large, relatively flat castings.113.2.6The Sand Casting OperationAfter the mold has been shaped and the cores have been placed in position, the two halves (cope and drag) are closed, clamped, and weighted down. They are weighted to prevent the separation of the mold sections under the pressure exerted when the molten metal is poured into the mold cavity.The design of the gating system is important for proper delivery of the molten metal into the mold cavity. As described, turbulence must be minimized, air and gases must be allowed to escape by such means as vents, and proper temperature gradients must be established and maintained to minimize shrinkage and porosity. The design of risers is also important in order to supply the necessary molten metal during solidification of the casting. The pouring basin may also serve as a riser. A complete sequence of operations in sand casting is shown in Fig. 3-9. In Fig. 3-9(a), a mechanical drawing of the part is used to generate a design for the pattern. Considerations such as part shrinkage and draft must be built into the drawing. In (b)~(c), patterns have been mounted on plates equipped with pins for alignment. Note the presence of core prints designed to hold the core in place. In (d)~(e), core boxes produce core halves, which are pasted together. The cores will be used to produce the hollow area of the part shown in (a). In (f), the cope half of the mold is assembled by securing the cope pattern plate to the flask with aligning pins, and attaching inserts to form the sprue and risers. In (g), the flask is rammed with sand and the plate and inserts are removed. In (h), the drag half is produced in a similar manner, with the pattern inserted. A bottom board is placed below the drag and aligned with pins. In (i), the pattern, flask, and bottom board are inverted, and the pattern is withdrawn, leaving the appropriate imprint. In (j), the core is set in place within the drag cavity. In (k), the mold is closed by placing the cope on top of the drag and securing the assembly with pins. The flasks are then subjected to pressure to counteract buoyant forces in the liquid, which might lift the cope. In (l), after the metal solidifies, the casting is removed from the mold. In (m), the sprue and risers are cut off and recycled, and the casting is cleaned, inspected, and heat treated (when necessary).After solidification, the casting is shaken out of its mold, and the sand and oxide layers adhering to the casting are removed by vibration (using a shaker) or by sand blasting. Ferrous castings are also cleaned by blasting with steel shot (shot blasting) or grit. The risers and gates are cut off by oxyfuel-gas cutting, sawing, shearing, andabrasive wheels, or they are trimmed in dies. Gates and risers on steel castings are also removed with air carbon-arc or powder-injection torches. Castings may be cleaned by electrochemical means or by pickling with chemicals to remove surface oxides.(a) (b) (c) Core printsMechanical drawing of part (d) (e)Core boxesCore printsCope pattern plateCore halvespasted together(f)FlaskGateDrag pattern plateRisers SprueCope ready for sand(g) (h) (i)Cope after ramming withsand and removing pattern, sprue, and risers Drag ready for sandDrag afterremoving pattern(j)CopeDrag (k)(l)(m)Drag with core set in place ClosingpinsCope and dragassembled readyfor pouringCasting asremoved frommold; heat treatedCasting readyfor shipmentFig. 3-9 Schematic illustration of the sequence of operations for sand castingAlmost all commercially-used metals can be sand cast. The surface finish obtained is largely a function of the materials used in making the mold. Dimensional accuracy is not as good as that of other casting processes. However, intricate shapes can be cast by this process, such as cast-iron engine blocks and very large propellers for ocean liners. Sand casting can be economical for relatively small production runs, and equipment costs are generally low.The surface of castings is important in subsequent machining operations, because machi- nability can be adversely affected if the castings are not cleaned properly and sand particles remain on the surface. If regions of the casting have not formed properly or have formedincompletely, the defects may be repaired by filling them with weld metal. Sand-mold castings generally have rough, grainy surfaces, depending on the quality of the mold and the materials used.The casting may subsequently be heat-treated to improve certain properties needed for its intended service use; these processes are particularly important for steel castings. Finishing operations may involve machining straightening, or forging with dies to obtain final dimensions.Minor surface imperfections may also be filled with a metal-filled epoxy, especially for cast-iron castings because they are difficult to weld. Inspection is an important final step and is carried out to ensure that the casting meets all design and quality control requirements.第三章铸造模具3.1 铸造第一批铸件是在公元前4000年至公元前3000年制造的。
注塑模具中英文对照外文翻译文献
中英文对照资料外文翻译Integrated simulation of the injection molding process withstereolithography moldsAbstract Functional parts are needed for design verification testing, field trials, customer evaluation, and production planning. By eliminating multiple steps, the creation of the injection mold directly by a rapid prototyping (RP) process holds the best promise of reducing the time and cost needed to mold low-volume quantities of parts. The potential of this integration of injection molding with RP has been demonstrated many times. What is missing is the fundamental understanding of how the modifications to the mold material and RP manufacturing process impact both the mold design and the injection molding process. In addition, numerical simulation techniques have now become helpful tools of mold designers and process engineers for traditional injection molding. But all current simulation packages for conventional injection molding are no longer applicable to this new type of injection molds, mainly because the property of the mold material changes greatly. In this paper, an integrated approach to accomplish a numerical simulation of injection molding into rapid-prototyped molds is established and a corresponding simulation system is developed. Comparisons with experimental results are employed for verification, which show that the present scheme is well suited to handle RP fabricated stereolithography (SL) molds.Keywords Injection molding Numerical simulation Rapid prototyping1 IntroductionIn injection molding, the polymer melt at high temperature is injected into the mold under high pressure [1]. Thus, the mold material needs to have thermal and mechanical properties capable of withstanding the temperatures and pressures of the molding cycle. The focus of many studies has been to create theinjection mold directly by a rapid prototyping (RP) process. By eliminating multiple steps, this method of tooling holds the best promise of reducing the time and cost needed to createlow-volume quantities of parts in a production material. The potential of integrating injection molding with RP technologies has been demonstrated many times. The properties of RP molds are very different from those of traditional metal molds. The key differences are the properties of thermal conductivity and elastic modulus (rigidity). For example, the polymers used in RP-fabricated stereolithography (SL) molds have a thermal conductivity that is less than one thousandth that of an aluminum tool. In using RP technologies to create molds, the entire mold design and injection-molding process parameters need to be modified and optimized from traditional methodologies due to the completely different tool material. However, there is still not a fundamental understanding of how the modifications to the mold tooling method and material impact both the mold design and the injection molding process parameters. One cannot obtain reasonable results by simply changing a few material properties in current models. Also, using traditional approaches when making actual parts may be generating sub-optimal results. So there is a dire need to study the interaction between the rapid tooling (RT) process and material and injection molding, so as to establish the mold design criteria and techniques for an RT-oriented injection molding process.In addition, computer simulation is an effective approach for predicting the quality of molded parts. Commercially available simulation packages of the traditional injection molding process have now become routine tools of the mold designer and process engineer [2]. Unfortunately, current simulation programs for conventional injection molding are no longer applicable to RP molds, because of the dramatically dissimilar tool material. For instance, in using the existing simulation software with aluminum and SL molds and comparing with experimental results, though the simulation values of part distortion are reasonable for the aluminum mold, results are unacceptable, with the error exceeding 50%. The distortion during injection molding is due to shrinkage and warpage of the plastic part, as well as the mold. For ordinarily molds, the main factor is the shrinkage and warpage of the plastic part, which is modeled accurately in current simulations. But for RP molds, the distortion of the mold has potentially more influence, which have been neglected in current models. For instance, [3] used a simple three-step simulation process to consider the mold distortion, which had too much deviation.In this paper, based on the above analysis, a new simulation system for RP molds is developed. The proposed system focuses on predicting part distortion, which is dominating defect in RP-molded parts. The developed simulation can be applied as an evaluation tool for RP mold design and process opti mization. Our simulation system is verified by an experimental example.Although many materials are available for use in RP technologies, we concentrate on usingstereolithography (SL), the original RP technology, to create polymer molds. The SL process uses photopolymer and laser energy to build a part layer by layer. Using SL takes advantage of both the commercial dominance of SL in the RP industry and the subsequent expertise base that has been developed for creating accurate, high-quality parts. Until recently, SL was primarily used to create physical models for visual inspection and form-fit studies with very limited func-tional applications. However, the newer generation stereolithographic photopolymers have improved dimensional, mechanical and thermal properties making it possible to use them for actual functional molds.2 Integrated simulation of the molding process2.1 MethodologyIn order to simulate the use of an SL mold in the injection molding process, an iterative method is proposed. Different software modules have been developed and used to accomplish this task. The main assumption is that temperature and load boundary conditions cause significant distortions in the SL mold. The simulation steps are as follows:1The part geo metry is modeled as a solid model, which is translated to a file readable by the flow analysis package.2Simulate the mold-filling process of the melt into a pho topolymer mold, which will output the resulting temperature and pressure profiles.3Structural analysis is then performed on the photopolymer mold model using the thermal and load boundary conditions obtained from the previous step, which calculates the distortion that the mold undergo during the injection process.4If the distortion of the mold converges, move to the next step. Otherwise, the distorted mold cavity is then modeled (changes in the dimensions of the cavity after distortion), and returns to the second step to simulate the melt injection into the distorted mold.5The shrinkage and warpage simulation of the injection molded part is then applied, which calculates the final distor tions of the molded part.In above simulation flow, there are three basic simulation mod ules.2. 2 Filling simulation of the melt2.2.1 Mathematical modelingIn order to simulate the use of an SL mold in the injection molding process, an iterativemethod is proposed. Different software modules have been developed and used to accomplish this task. The main assumption is that temperature and load boundary conditions cause significant distortions in the SL mold. The simulation steps are as follows:1. The part geometry is modeled as a solid model, which is translated to a file readable by the flow analysis package.2. Simulate the mold-filling process of the melt into a photopolymer mold, which will output the resulting temperature and pressure profiles.3. Structural analysis is then performed on the photopolymer mold model using the thermal and load boundary conditions obtained from the previous step, which calculates the distortion that the mold undergo during the injection process.4. If the distortion of the mold converges, move to the next step. Otherwise, the distorted mold cavity is then modeled (changes in the dimensions of the cavity after distortion), and returns to the second step to simulate the melt injection into the distorted mold.5. The shrinkage and warpage simulation of the injection molded part is then applied, which calculates the final distortions of the molded part.In above simulation flow, there are three basic simulation modules.2.2 Filling simulation of the melt2.2.1 Mathematical modelingComputer simulation techniques have had success in predicting filling behavior in extremely complicated geometries. However, most of the current numerical implementation is based on a hybrid finite-element/finite-difference solution with the middleplane model. The application process of simulation packages based on this model is illustrated in Fig. 2-1. However, unlike the surface/solid model in mold-design CAD systems, the so-called middle-plane (as shown in Fig. 2-1b) is an imaginary arbitrary planar geometry at the middle of the cavity in the gap-wise direction, which should bring about great inconvenience in applications. For example, surface models are commonly used in current RP systems (generally STL file format), so secondary modeling is unavoidable when using simulation packages because the models in the RP and simulation systems are different. Considering these defects, the surface model of the cavity is introduced as datum planes in the simulation, instead of the middle-plane.According to the previous investigations [4–6], fillinggoverning equations for the flow and temperature field can be written as:where x, y are the planar coordinates in the middle-plane, and z is the gap-wise coordinate; u, v,w are the velocity components in the x, y, z directions; u, v are the average whole-gap thicknesses; and η, ρ,CP (T), K(T) represent viscosity, density, specific heat and thermal conductivity of polymer melt, respectively.Fig.2-1 a–d. Schematic procedure of the simulation with middle-plane model. a The 3-D surface model b The middle-plane model c The meshed middle-plane model d The display of the simulation result In addition, boundary conditions in the gap-wise direction can be defined as:where TW is the constant wall temperature (shown in Fig. 2a).Combining Eqs. 1–4 with Eqs. 5–6, it follows that the distributions of the u, v, T, P at z coordinates should be symmetrical, with the mirror axis being z = 0, and consequently the u, v averaged in half-gap thickness is equal to that averaged in wholegap thickness. Based on this characteristic, we can divide the whole cavity into two equal parts in the gap-wise direction, as described by Part I and Part II in Fig. 2b. At the same time, triangular finite elements are generated in the surface(s) of the cavity (at z = 0 in Fig. 2b), instead of the middle-plane (at z = 0 in Fig. 2a). Accordingly, finite-difference increments in the gapwise direction are employed only in the inside of the surface(s) (wall to middle/center-line), which, in Fig. 2b, means from z = 0 to z = b. This is single-sided instead of two-sided with respect to the middle-plane (i.e. from the middle-line to two walls). In addition, the coordinate system is changed from Fig. 2a to Fig. 2b to alter the finite-element/finite-difference scheme, as shown in Fig. 2b. With the above adjustment, governing equations are still Eqs. 1–4. However, the original boundary conditions inthe gapwise direction are rewritten as:Meanwhile, additional boundary conditions must be employed at z = b in order to keep the flows at the juncture of the two parts at the same section coordinate [7]:where subscripts I, II represent the parameters of Part I and Part II, respectively, and Cm-I and Cm-II indicate the moving free melt-fronts of the surfaces of the divided two parts in the filling stage.It should be noted that, unlike conditions Eqs. 7 and 8, ensuring conditions Eqs. 9 and 10 are upheld in numerical implementations becomes more difficult due to the following reasons:1. The surfaces at the same section have been meshed respectively, which leads to a distinctive pattern of finite elements at the same section. Thus, an interpolation operation should be employed for u, v, T, P during the comparison between the two parts at the juncture.2. Because the two parts have respective flow fields with respect to the nodes at point A and point C (as shown in Fig. 2b) at the same section, it is possible to have either both filled or one filled (and one empty). These two cases should be handled separately, averaging the operation for the former, whereas assigning operation for the latter.3. It follows that a small difference between the melt-fronts is permissible. That allowance can be implemented by time allowance control or preferable location allowance control of the melt-front nodes.4. The boundaries of the flow field expand by each melt-front advancement, so it is necessary to check the condition Eq. 10 after each change in the melt-front.5. In view of above-mentioned analysis, the physical parameters at the nodes of the same section should be compared and adjusted, so the information describing finite elements of the same section should be prepared before simulation, that is, the matching operation among the elements should be preformed.Fig. 2a,b. Illustrative of boundary conditions in the gap-wise direction a of the middle-plane model b of thesurface model2.2.2 Numerical implementationPressure field. In modeling viscosity η, which is a function of shear rate, temperature and pressure of melt, the shear-thinning behavior can be well represented by a cross-type model such as:where n corresponds to the power-law index, and τ∗ characterizes the shear stress level of the transition region between the Newtonian and power-law asymptotic limits. In terms of an Arrhenius-type temperature sensitivity and exponential pressure dependence, η0(T, P) can be represented with reasonable accuracy as follows:Equations 11 and 12 constitute a five-constant (n, τ∗, B, Tb, β) representation for viscosity. The shear rate for viscosity calculation is obtained by:Based on the above, we can infer the following filling pressure equation from the governing Eqs. 1–4:where S is calculated by S = b0/(b−z)2η d z. Applying the Galerkin method, the pressure finite-element equation is deduced as:where l_ traverses all elements, including node N, and where I and j represent the local node number in element l_ corresponding to the node number N and N_ in the whole, respectively. The D(l_) ij is calculated as follows:where A(l_) represents triangular finite elements, and L(l_) i is the pressure trial function in finite elements.Temperature field. To determine the temperature profile across the gap, each triangular finite element at the surface is further divided into NZ layers for the finite-difference grid.The left item of the energy equation (Eq. 4) can be expressed as:where TN, j,t represents the temperature of the j layer of node N at time t.The heat conduction item is calculated by:where l traverses all elements, including node N, and i and j represent the local node number in element l corresponding to the node number N and N_ in the whole, respectively.The heat convection item is calculated by:For viscous heat, it follows that:Substituting Eqs. 17–20 into the energy equation (Eq. 4), the temperature equation becomes:2.3 Structural analysis of the moldThe purpose of structural analysis is to predict the deformation occurring in the photopolymer mold due to the thermal and mechanical loads of the filling process. This model is based on a three-dimensional thermoelastic boundary element method (BEM). The BEM is ideally suited for this application because only the deformation of the mold surfaces is of interest. Moreover, the BEM has an advantage over other techniques in that computing effort is not wasted on calculating deformation within the mold.The stresses resulting from the process loads are well within the elastic range of the mold material. Therefore, the mold deformation model is based on a thermoelastic formulation. The thermal and mechanical properties of the mold are assumed to be isotropic and temperature independent.Although the process is cyclic, time-averaged values of temperature and heat flux are used for calculating the mold deformation. Typically, transient temperature variations within a mold have been restricted to regions local to the cavity surface and the nozzle tip [8]. The transients decay sharply with distance from the cavity surface and generally little variation is observed beyond distances as small as 2.5 mm. This suggests that the contribution from the transients to the deformation at the mold block interface is small, and therefore it is reasonable to neglect the transient effects. The steady state temperature field satisfies Laplace’s equation 2T = 0 and the time-averaged boundary conditions. The boundary conditions on the mold surfaces are described in detail by Tang et al. [9]. As for the mechanical boundary conditions, the cavity surface is subjected to the melt pressure, the surfaces of the mold connected to the worktable are fixed in space, and other external surfaces are assumed to be stress free.The derivation of the thermoelastic boundary integral formulation is well known [10]. It is given by:where uk, pk and T are the displacement, traction and temperature,α, ν represent the thermal expansion coefficient and Poisson’s ratio of the material, and r = |y−x|. clk(x) is the surfacecoefficient which depends on the local geometry at x, the orientation of the coordinate frame and Poisson’s ratio for the domain [11]. The fundamental displacement ˜ulk at a point y in the xk direction, in a three-dimensional infinite isotropic elastic domain, results from a unit load concentrated at a point x acting in the xl direction and is of the form:where δlk is the Kronecker delta function and μ is the shear modulus of the mold material.The fundamental traction ˜plk , measured at the point y on a surface with unit normal n, is:Discretizing the surface of the mold into a total of N elements transforms Eq. 22 to:where Γn refers to the n th surface element on the domain.Substituting the appropriate linear shape functions into Eq. 25, the linear boundary element formulation for the mold deformation model is obtained. The equation is applied at each node on the discretized mold surface, thus giving a system of 3N linear equations, where N is the total number of nodes. Each node has eight associated quantities: three components of displacement, three components of traction, a temperature and a heat flux. The steady state thermal model supplies temperature and flux values as known quantities for each node, and of the remaining six quantities, three must be specified. Moreover, the displacement values specified at a certain number of nodes must eliminate the possibility of a rigid-body motion or rigid-body rotation to ensure a non-singular system of equations. The resulting system of equations is assembled into a integrated matrix, which is solved with an iterative solver.2.4 Shrinkage and warpage simulation of the molded partInternal stresses in injection-molded components are the principal cause of shrinkage and warpage. These residual stresses are mainly frozen-in thermal stresses due to inhomogeneous cooling, when surface layers stiffen sooner than the core region, as in free quenching. Based onthe assumption of the linear thermo-elastic and linear thermo-viscoelastic compressible behavior of the polymeric materials, shrinkage and warpage are obtained implicitly using displacement formulations, and the governing equations can be solved numerically using a finite element method.With the basic assumptions of injection molding [12], the components of stress and strain are given by:The deviatoric components of stress and strain, respectively, are given byUsing a similar approach developed by Lee and Rogers [13] for predicting the residual stresses in the tempering of glass, an integral form of the viscoelastic constitutive relationships is used, and the in-plane stresses can be related to the strains by the following equation:Where G1 is the relaxation shear modulus of the material. The dilatational stresses can be related to the strain as follows:Where K is the relaxation bulk modulus of the material, and the definition of α and Θ is:If α(t) = α0, applying Eq. 27 to Eq. 29 results in:Similarly, applying Eq. 31 to Eq. 28 and eliminating strain εxx(z, t) results in:Employing a Laplace transform to Eq. 32, the auxiliary modulus R(ξ) is given by:Using the above constitutive equation (Eq. 33) and simplified forms of the stresses and strains in the mold, the formulation of the residual stress of the injection molded part during the cooling stage is obtain by:Equation 34 can be solved through the application of trapezoidal quadrature. Due to the rapid initial change in the material time, a quasi-numerical procedure is employed for evaluating the integral item. The auxiliary modulus is evaluated numerically by the trapezoidal rule.For warpage analysis, nodal displacements and curvatures for shell elements are expressed as:where [k] is the element stiffness matrix, [Be] is the derivative operator matrix, {d} is the displacements, and {re} is the element load vector which can be evaluated by:The use of a full three-dimensional FEM analysis can achieve accurate warpage results, however, it is cumbersome when the shape of the part is very complicated. In this paper, a twodimensional FEM method, based on shell theory, was used because most injection-molded parts have a sheet-like geometry in which the thickness is much smaller than the other dimensions of the part. Therefore, the part can be regarded as an assembly of flat elements to predict warpage. Each three-node shell element is a combination of a constant strain triangular element (CST) and a discrete Kirchhoff triangular element (DKT), as shown in Fig. 3. Thus, the warpage can be separated into plane-stretching deformation of the CST and plate-bending deformation of the DKT, and correspondingly, the element stiffness matrix to describe warpage can also be divided into the stretching-stiffness matrix and bending-stiffness matrix.Fig. 3a–c. Deformation decomposition of shell element in the local coordinate system. a In-plane stretchingelement b Plate-bending element c Shell element3 Experimental validationTo assess the usefulness of the proposed model and developed program, verification is important. The distortions obtained from the simulation model are compared to the ones from SL injection molding experiments whose data is presented in the literature [8]. A common injection molded part with the dimensions of 36×36×6 mm is considered in the experiment, as shown in Fig. 4. The thickness dimensions of the thin walls and rib are both 1.5 mm; and polypropylene was used as the injection material. The injection machine was a production level ARGURY Hydronica 320-210-750 with the following process parameters: a melt temperature of 250 ◦C; an ambient temperature of 30 ◦C; an injection pressure of 13.79 MPa; an injection time of 3 s; and a cooling time of 48 s. The SL material used, Dupont SOMOSTM 6110 resin, has the ability to resist temperatures of up to 300 ◦C temperatures. As mentioned above, thermal conductivity of the mold is a major factor that differentiates between an SL and a traditional mold. Poor heat transfer in the mold would produce a non-uniform temperature distribution, thus causing warpage that distorts the completed parts. For an SL mold, a longer cycle time would be expected. The method of using a thin shell SL mold backed with a higher thermal conductivity metal (aluminum) was selected to increase thermal conductivity of the SL mold.Fig. 4. Experimental cavity modelFig. 5. A comparison of the distortion variation in the X direction for different thermal conductivity; where “Experimental”, “present”, “three-step”, and “conventional” mean the results of the experimental, the presented simulation, the three-step simulation process and the conventional injection molding simulation, respectively.Fig. 6. Comparison of the distortion variation in the Y direction for different thermal conductivitiesFig. 7. Comparison of the distortion variation in the Z direction for different thermal conductivitiesFig. 8. Comparison of the twist variation for different thermal conductivities For this part, distortion includes the displacements in three directions and the twist (the difference in angle between two initially parallel edges). The validation results are shown in Fig.5 to Fig. 8. These figures also include the distortion values predicted by conventional injection molding simulation and the three-step model reported in [3].4 ConclusionsIn this paper, an integrated model to accomplish the numerical simulation of injection molding into rapid-prototyped molds is established and a corresponding simulation system is developed. For verification, an experiment is also carried out with an RPfabricated SL mold.It is seen that a conventional simulation using current injection molding software breaks down for a photopolymer mold. It is assumed that this is due to the distortion in the mold caused by the temperature and load conditions of injection. The three-step approach also has much deviation. The developed model gives results closer to experimental.Improvement in thermal conductivity of the photopolymer significantly increases part quality. Since the effect of temperature seems to be more dominant than that of pressure (load), an improvement in the thermal conductivity of the photopolymer can improve the part quality significantly.Rapid Prototyping (RP) is a technology makes it possible to manufacture prototypes quickly and inexpensively, regardless of their complexity. Rap id Tooling (RT) is the next step in RP’s steady progress and much work is being done to obtain more accurate tools to define the parameters of the process. Existing simulation tools can not provide the researcher with a useful means of studying relative changes. An integrated model, such as the one presented in this paper, is necessary to obtain accurate predictions of the actual quality of final parts. In the future, we expect to see this work expanded to develop simulations program for injection into RP molds manufactured by other RT processes.References1. Wang KK (1980) System approach to injection molding process. Polym-Plast Technol Eng 14(1):75–93.2. Shelesh-Nezhad K, Siores E (1997) Intelligent system for plastic injection molding process design. J Mater Process Technol 63(1–3):458–462.3. Aluru R, Keefe M, Advani S (2001) Simulation of injection molding into rapid-prototyped molds. Rapid Prototyping J 7(1):42–51.4. Shen SF (1984) Simulation of polymeric flows in the injection molding process. Int J Numer Methods Fluids 4(2):171–184.5. Agassant JF, Alles H, Philipon S, Vincent M (1988) Experimental and theoretical study of the injection molding of thermoplastic materials. Polym Eng Sci 28(7):460–468.6. Chiang HH, Hieber CA, Wang KK (1991) A unified simulation of the filling and post-filling stages in injection molding. Part I: formulation. Polym Eng Sci 31(2):116–124.7. Zhou H, Li D (2001) A numerical simulation of the filling stage in injection molding based on a surface model. Adv Polym Technol 20(2):125–131.8. Himasekhar K, Lottey J, Wang KK (1992) CAE of mold cooling in injection molding using a three-dimensional numerical simulation. J EngInd Trans ASME 114(2):213–221.9. Tang LQ, Pochiraju K, Chassapis C, Manoochehri S (1998) Computeraided optimization approach for the design of injection mold cooling systems. J Mech Des, Trans ASME 120(2):165–174.10. Rizzo FJ, Shippy DJ (1977) An advanced boundary integral equation method for three-dimensional thermoelasticity. Int J Numer Methods Eng 11:1753–1768.11. Hartmann F (1980) Computing the C-matrix in non-smooth boundary points. In: New developments in boundary element methods, CML Publications, Southampton, pp 367–379.12. Chen X, Lama YC, Li DQ (2000) Analysis of thermal residual stress in plastic injection molding. J Mater Process Technol 101(1):275–280.13. Lee EH, Rogers TG (1960) Solution of viscoelastic stress analysis problems using measured creep or relaxation function. J Appl Mech 30(1):127–134.14. Li Y (1997) Studies in direct tooling using stereolithography. Dissertation, University of Delaware, Newark, DE..。
注塑模具产品开发中英文对照外文翻译文献
注塑模具产品开发中英⽂对照外⽂翻译⽂献中英⽂对照外⽂翻译⽂献(⽂档含英⽂原⽂和中⽂翻译)参数化建模滚珠丝杠主轴摘要产品开发过程的数值优化可以成功地应⽤于产品设计的早期阶段。
在滚珠丝杠驱动器很常见的情况下，动态现象⼤多数根据滚珠丝杠本⾝的⼏何形状⽽定。
轴向和扭转刚度相同的丝杠，最⼤速度和加速度不仅取决于伺服电机，也取决于丝杆直径，凹槽斜率和球半径。
此外联轴器的设计参数影响使优化变得更加困难。
为了捕捉这些影响，有效的数据（通常是有限元或MBS）模型是必要的。
在这项⼯作中，⼀个新的更准确和有效的计算滚珠丝杠主轴轴向和扭转刚度被提出。
我们分析得到描绘的丝杠⼏何参数对⼤多数刚度的依赖关系的参数⽅程。
此外，我们增加⼀个确定函数的分析模型，从⽽提⾼了准确性。
在许多例⼦帮助下，所提出的分析模型针对有限元模型和⽬录数据进⾏了验证。
1 绪论滚珠丝杠主轴的轴向和扭转刚度中对滚珠丝杠驱动器动态特性起着重要作⽤，因为它基本上决定了滚珠丝杠驱动器的第⼀个和第⼆个特征值。
当⽤有限元建模时，滚珠丝杠驱动器的螺纹通常被忽略并且⼀些平均直径被⽤来建⽴简化的滚珠丝杆模型。
因此，关键是得到最接近的平均直径。
在⼤多数关于前⼈建模与仿真下，滚珠丝杆传动建模集中在滚珠丝刚螺母和滚珠丝杠主轴部件。
Jarosch ⽐较了不同类型的滚珠丝杠，但考虑到主轴简化为圆柱体，直径等于主轴外径，从⽽忽视了削减主轴螺纹。
随着了解的实际轴向uz k 和单位长度的螺杆扭转刚度z k ?，平均直径可以被计算为E k d uzuz m π4,= （1） 4,32G k d zz m π??= （2）杨⽒模量和剪切模量分别为E 和G 。
平均直径总是⽐主轴外径⼩。
对于每个刚度我们得到两个不同的平均直径。
这取决于每个应⽤的平均直径的最好选择。
这两个直径也可以做到线性组合。
⼀般滚珠丝杠制造商提供轴向刚度数据，但没有扭转刚度。
基于这个原因我们使⽤有限元法（FEM ）来计算两者滚珠丝杠主轴轴向和扭转刚度。
注射模具的介绍外文翻译、中英文翻译、外文文献翻译
The introdution of the Injection Mold1. Mold basic knowledge1.1 IntroductionThere is a close relationship with all kinds of mold,which are refered to our daily production, and life in the use of the various tools and products, the large base of the machine tool, the body shell, the first embryo to a small screws, buttons, as well as various home appliances shell. Mold’s shape determine the shape of these products, mold’s precision and machining quality determine the quality of these products,too. Because of a variety of products, appearance, specifications and the different uses,mold devide into Die Casting into the mould, die forging, die-casting mould, Die, and so on other non - plastic molds, as well as plastic mold. In recent years, with the rapid development of the plastics industry, and GM and engineering plastics in areas such as strength and accuracy of the continuous enhancement , the scope of the application of plastic products have also constantly expanded, such as: household appliances, instrumentation, construction equipment, automotive, daily hardware, and many other fields, the proportion of plastic products is rapidly increasing. A rational design of plastic parts often can replace much more traditional metal pieces. The trend of industrial products and daily products plasticed is rising day after day.1.2 Mold general definitionIn the industrial production，with the various press and the special instruments which installed in the press,it produces the required shape parts or products through pressure on the metal or non-metallic materials, this special instruments collectively call as the mold.1.3 Mold general classificationMold can be divided into plastic and non - plastic mould: (1) Non-plastic mould: Die Casting, forging Die, Die, die-casting mould and so on. A. Die Casting - taps, pig iron platformB. Forging Die - car body C. Die - computer panel D. Die Casting Die - superalloy, cylinder body (2) For the production technology and production, the plastic mold are divided into different products: A. Injection molding die - TV casing, keyboard button (the most common application) B. Inflatable module - drink bottles C. Compression molding die - bakeliteswitches, scientific Ciwan dish D. Transfer molding die - IC products E. Extrusion die - of glue, plastic bags F. Hot forming die - transparent shell molding packaging G. Rotomoulding mode - Flexible toy doll. Injection Molding is the most popurlar method in plastics producing process. The method can be applied to all parts of thermoplastic and some of thermosetting plastics, the quantity of plastic production is much more than any other forming method.Injection mold as one of the main toolsof injection molding processing,whosh production efficiency is low or high in the quality of precision、manufacturing cycle and the process of injection molding and so on,directly affect the quality of products, production, cost and product updates, at the same time it also determines the competitiveness of enterprises in the market's response capacity and speed. Injection Mold consists of a number of plate which mass with the various component parts. It divided into: A molding device (Die, punch)B positioning system (I. column I. sets) C fixtures (the word board, code-pit) D cooling system (carrying water hole) E thermostat system (heating tubes, the hotline) F-Road System (jack Tsui hole, flow slot, streaming Road Hole) G ejection system (Dingzhen, top stick).1.4 Type of moldIt can be divided into three categories according to gating system with the different type of mold :(1) intake die: Runner and gate at the partig line,it will strip together with products when in the open mode,it is the most simple of design, easy processing and lower costing.So more people operations by using large intake system. (2) small inlet die:It general stay in the products directly,but runner and gate are not at the partig line.Therefore,it should be design a multi-outlet parting line.And then it is more complex in the designing, more difficult in processing, generally chosing the small inlet die is depending on the product’s requirements. (3) hot runner die:It consists of heat gate, heat runner plate, temperature control box. Hot runner molds are two plate molds with a heated runner system inside one half of the mold. A hot runner system is divided into two parts: the manifold and the drops. The manifold has channels that convey the plastic on a single plane, parallel to the parting line, to a point above the cavity. The drops, situated perpendicular to the manifold, convey the plastic from the manifold to the part. The advantages of hot runner system ：(1)No outlet expected, no need processing, the whole process fully automated, save time and enhance the efficiency of the work. (2) small pressure loss.2、Injection MoldThere are many rules for designing molds.These rules and standard practices are based on logic,past experience,convenience,and economy.For designing,mold making,and molding,it is usually of advantage to follow the rules.But occasionally,it may work out better if a rule is ignored and an alternative way is selected.In some texts,the most common rules are noted,but the designer will learn only from experience which way to go.The designer must ever be open to new ideas and methods,to new molding and mold material that may affect these rules.The process consists of feeding a plastic compound in powdered or granular form from a hopper through metering and melting stages and then injecting it into a mold.Injection molding process: Mold is a production of plastic tool. It consists of several parts and this group contains forming cavities. When it injects molding, mold clamping in the injection molding machine, melting plastic is Injected forming cavities and cooling stereotypes in it, then it separate upper and lower die,it will push the production from the cavity in order to leave the mold through ejection system, finally mold close again and prepared the next injection. The entire process of injection is carried out of the cycle.An injection mold consists of at least two halves that are fastened to the two platens of the injection molding machine so that can be opened and closed.In the closed position,the product-forming surfaces of the two mold halves define the mold cavity into which the plastic melt is injected via the runner system and the gate.Cooling provisions in the mold provide for cooling and solidification of the molded product so that it can be subsequently ejected.For product ejection to occur,the mold must open.The shape of the molded product determines whether it can be ejected simply by opening the two mold halves or whether undercuts must be present.The design of a mold is dictated primarily by the shape of the product to be molded and the provisions necessary for product ejection.Injection-molded products can be classified as:1).Products without undercuts.2).products with external undercuts of lateral openings.3).products with internal undercuts.4).products with external and internal undercuts.3.The composition of injection mold3.1 Mold Cavity SpaceThe mold cavity space is a shape inside the mold,when the molding material is forced into this space it will take on the shape of the cavity space.In injection molding the plastic is injected into the cavity space with high pressure,so the mold must be strong enough to resist the injection pressure without deforming.3.2 Number of CavitiesMany molds,particularly molds for larger products,ate built for only 1 cavity space,but many molds,especially large production molds,are built with 2 or more cavities.The reason for this is purely economical.It takes only little more time to inject several cavities than to inject one.Today,most multicavity molds are built with a preferred number ofcavities:2,4,6,8,12,16,24,32,48,64,96,128.These numbers are selected because the cavities can be easily arranged in a rectangular pattern,which is easier for designing and dimensioning,for manufacturing,and for symmetry around the center of the machine ,which is highly desirable to ensure equal clamping force for each cavity.3.3 Cavity and CoreBy convention,the hollow portion of the cavity space is called the cavity.The matching,often raised portion of the cavity space is called the core.Most plastic products are cup-shaped.This does not mean that they look like a cup,but they do have an inside and an outside.The outside of the product is formed by the cavity, the inside by the ually,the cavities are placed in the mold half that is mounted on the injection side,while the cores are placed in the moving half of the mold.The reason for this is that all injection molding machines provide an ejection mechanism on the moving platen and the products tend to shrink onto and cling to the core,from where they are then ejected.Most injection molding machines do not provide ejection mechanisms on the injection side.For moulds containing intricate impressions,and for multi-impression moulds, it is not satisfactory to attempt to machine the cavity and core plates from single blocks of steel as with integer moulds. The cavity and core give the molding its external and internal shapes respectively, the impression imparting the whole of the form to the molding.3.4 The Parting LineTo be able to produce a mold,we must have ta least two separate mold halves,with the cavity in one side and the core in the other.The separation between these plates is called the parting line,and designated P/L.Actually,this is a parting area or plane,but,by cinvention,in this intext it is referred to as a line. The parting surfaces of a mould are those portion of both mould plates, adjacent to the impressions, which butt together to form a seal and prevent the loss of plastic material from the impression.The parting line can have any shape, many moldings are required which have a parting line which lies on a non-planar or curved surface,but for ease of mold manufacturing,it is preferable to have it in one plane.The parting line is always at the widest circumference of the product,to make ejection of the product from the mold possible.With some shapes it may be necessary to offset the P/L,or to have it at an angle,but in any event it is best to have is so that itan be easily machined,and often ground, to ensure that it shuts off tightly when the mold is clamped during injection.If the parting line is poorly finished the plastic will escape,which shows up on the product as an unsightly sharp projection,which must then be removed;otherwise,the product could be unusable.There is even a danger that the plastic could squirt out of the mold and do personal danger.3.5 Runners and GatesNow,we must add provisions for bringing the plastic into these cavity spaces.This must be done with enough pressure so that the cavity spaces are filled completely before the plastic "freezes"(that is,cools so much that the plastic cannot flow anymore).The flow passages are the sprue,from wherethe machine nozzle contactss the mold,the runners,which distribute the plastic to the individual cavities, the wall of the runner channel must be smooth to prevent any restriction to flow. Also, as the runner has to be removed with the molding, there must be no machine marks left which would tend to retain the runner in the mould plate.And the gates which are small openings leading from the runner into the cavity space. The gate is a channel or orifice connecting the runner with the impression. It has a small cross-sectional area when compared with the rest of the feed system. The gate freezes soon after the impression is filled so that the injection plunger can be withdrawn without the probability of void being created in the molding by suck-back.4. The injection molding machine processInjection Mold is installed in the injection molding machine, and its injection molding process is completed by the injection molding machine. Following is the injection molding machine process.The molding machine uses a vacuum to move the plastic from the dryer to it's initial holding chamber. This chamber is actually a small hopper on the back of the "barrel" of the machine。
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外文资料翻译系部：机械工程系专业: 材料成型及控制工程一个描述电铸镍壳在注塑模具的应用的技术研究——Universidad de Las Palmas de Gran Canaria, Departamento de Ingenieria Mecanica, Spain摘要：在过去几年中快速成型技术及快速模具已被广泛开发利用. 在本文中,使用电芯作为核心程序对塑料注射模具分析. 通过差分系统快速成型制造外壳模型. 主要目的是分析电铸镍壳力学特征、研究相关金相组织,硬度,内部压力等不同方面，由这些特征参数以生产电铸设备的外壳. 最后一个核心是检验注塑模具.关键词：电镀；电铸；微观结构；镍1. 引言现代工业遇到很大的挑战，其中最重要的是怎么样提供更好的产品给消费者,更多种类和更新换代问题. 因此,现代工业必定产生更多的竞争性. 毫无疑问,结合时间变量和质量变量并不容易,因为他们经常彼此互为条件; 先进的生产系统将允许该组合以更加有效可行的方式进行，例如,如果是观测注塑系统的转变、我们得出的结论是,事实上一个新产品在市场上具有较好的质量它需要越来越少的时间快速模具制造技术是在这一领域, 中可以改善设计和制造注入部分的技术进步. 快速模具制造技术基本上是一个中小型系列的收集程序，在很短的时间内在可接受的精度水平基础上让我们获得模具的塑料部件。
其应用不仅在更加广阔而且生产也不断增多。
本文包括了很广泛的研究路线,在这些研究路线中我们可以尝试去学习，定义，分析，测试，提出在工业水平方面的可行性，从核心的注塑模具制造获取电铸镍壳，同时作为一个初始模型的原型在一个FDM设备上的快速成型。
不得不说的是,先进的电铸技术应用在无数的行业，但这一研究工作调查到什么程度,并根据这些参数,使用这种技术生产快速模具在技术上是可行的. 都产生一个准确的，系统化使用的方法以及建议的工作方法.2 制造过程的注塑模具薄镍外壳的核心是电铸,获得一个充满epoxic金属树脂的一体化的核心板块模具(图1)允许直接制造注射型多用标本，因为它们确定了新英格兰大学英文国际表卓华组织3167标准。
这样做的目的是确定力学性能的材料收集代表行业。
该阶段取得的核心[4]，根据这一方法研究了这项工作,有如下:a,用CAD系统设计的理想对象b模型制造的快速成型设备(频分多路系统). 所用材料将是一个ABS塑料c一个制造的电铸镍壳，已事先涂有导电涂料(必须有导电).d无外壳模型e核心的生产是背面外壳环氧树脂的抗高温与具有制冷的铜管管道.有两个腔的注塑模具、其中一个是电核心和其他直接加工的移动版. 因此,在同一工艺条件下，同时注入两个标准技术制造，获得相同的工作。
3 获得电壳:设备电镀是电解质时电流的化学变化,电解所形成的直流电有两个电极，阳极和阴极。
当电流流经电路，在离子溶液中转化为原子。
电镀液用于这项工作是由氨基磺酸镍400 毫升/升,氯化镍(10克/升)、硼酸(50克/升),allbrite SLA(30毫升/升),allbrite703(2毫升/升). 选择这种组合主要原因是我们考虑注塑模具程序是玻璃纤维. 氨基磺酸镍让我们获得可以接受的内部压力(测试不同工艺条件结果,而不是最佳工艺条件约2兆帕最高为50兆帕). 不过,这种内部压力是由touenesulfonamode 衍生物和甲醛水溶液使用的ALLbrite添加剂的结果。
这种添加剂也增加了壳的阻力. Allbrite703是一种可生物降解水溶液表使用剂氯化镍,有利于解决金属统一分布在阴极，提高导电性的问题。
硼酸作为PH值缓冲区。
该设备用于制造壳的测试如下：●聚丙烯:600毫米×400毫米×500毫米的尺寸●三聚四氟乙烯电阻器,每一个有800W●具有机械搅拌系统的阴极●循环和过滤系统用的泵和聚丙烯过滤器。
●充电整流器. 最大强度在连续50个A和连续电流电压介于0至16伏●篮钛镍阳极(镍硫回合电解镍)纯度99%以上●气体注入系统一旦电流密度( 1-22A/dm）,温度(35至55℃)和pH值,已经确定，执行参数以及测试的进程部分不可改变。
4 获得硬度电壳硬度的测试一直保持在相当高的很稳定的结果。
如图2，可以看到：电流密度值2.5到22A/dm，硬度值介于540到580高压，PH值为4+-0.2和温度为45摄氏度，如果PH减少到3.5和温度为55摄氏度，硬度为520以上，高压低于560.这一测试使常规组成不同于其他氨基磺酸镍，允许其经营更加广泛，然而，这种operatyivity将是一定的取决于其他因素，如内部压力，因为他可能的变异。
改变PH值，电流密度和温度等，另一方面，传统的硬度氨基磺酸镍承受的高压在200-250之间，远低于取得的一个实验结果的电压。
对于一个注塑模具，硬度可以接受的起点300高压这是必须考虑的，注塑模具中最常见的材料，有改善钢（290高压），整体淬火（520-595高压），casehardened钢铁（760-8--高压）等，以这样一种方式，可以看到，注塑模具硬度水平的镍是壳内的高范围的材料。
因为这是一个负责内部压力的塑料注射液，这种方式与环氧树脂灌浆将遵循它，相反对低韧性的壳补偿，这就是为什么它是必定尽可能的外壳厚度均匀，并没有重要的原因，如腐蚀。
5 金相组织为了分析金相结构、电流密度、温度主要变化. 在正面横向部分（垂直沉积）对样品进行了分析，为了方便地封装在树脂，抛光。
铭刻，在不同阶段的混合乙酸和硝酸。
该时刻间隔15,25,40,50之后再次抛光, 为了在金相显微镜下观察奥林巴斯PME3-ADL3.3X/10X 必须要说的是，这一条规定显示了图片之后的评论，用于制造该模型的壳在FDM快速成型机里融化的塑料材料（澳大利亚统计局）巩固和解决了该阶层。
后来在每一个层，挤出的模具都留下一个大约0.15毫米直径横向和纵向的线程。
因此，在表面可以看到细线表面头部的机器。
这些西路将作为参考信息解决镍的重复性问题。
重复性的模型将作为一个基本要素来评估注塑模具的表面纹理。
表1测试系列：表1. 检验系列系列pH 温度(℃)电流密度A/mm21 4.2 ± 0.2 55 2.222 3.9 ± 0.2 45 5.563 4.0 ± 0.2 45 10.004 4.0 ± 0.2 45 22.22图3说明该系列第一时刻表面的样本它显示了流道起点的频率复用机，这就是说，又一个很好的重复性。
它不能仍然要注意四舍五入结构。
在图4 系列2，经过第二次，可以看到一条线的流道的方式与以前的相比不太清楚。
在图5系列3虽然第二次时刻开始出现圆形晶结果是非常困难的。
此外，最黑暗的部分表明时刻不足的进程和组成。
这种现象表明，在低电流密度和高温条件下工作，得到更小的晶粒尺寸和壳重现性好，就是所需要的足够的应用程序。
如果分析横向平面进行的沉积，可以在所有测试样品和条件增长的结构层（图6），牺牲一个低延展性取得令人满意的高机械阻力，最重要的是添加剂的使用情况，氨基磺酸镍液的添加剂通常创建一个纤维和非层状结果[9].这个问题表明在任何情况下改变润湿剂，由于该层结构的决定因素是这种结构的应力减速器（ALLbriteSLA)。
另一方面，她也是测试的层状结构不同厚度中的电流密度.6 内部压力壳的一个主要特点是应该有其应用，如插入时要有一个低水平的内部压力。
测试不同的温度很电流密度，所采取的措施取决于阴极弯曲张力计法。
A钢测试控制使用侧固定和其他自由度固定（160毫米长，12.7毫米宽，0.3毫米厚）。
金属沉积只有在控制了机械拉伸力（拉深或压应力），才能计算内部压力。
弹性的角度来看，斯托尼模型应用，假定镍基质厚度，对部分钢材产生足够小（3微米）的影响。
在所有测试情况下，一个能够接受的应用程序在内部压力在50兆帕的极端条件下和2兆帕的最佳条件下产生。
得出的结论是，内部压力在不同的工作条件和参数没有明显的变化条件下。
7 校验注塑模具试验已进行了各种代表性热塑性材料如聚丙烯、高密度聚乙烯和PC、并进行了注射部件性能的分析，如尺寸，重量，阻力，刚度和柔性。
对壳的力学性能进行了拉伸破坏性测试和分析。
大约500个注射液在其余的条件下，进行了更多的检验总体而言, 为分析一种材料，重要的是注意到行为标本中的核心和那些加工腔之间的差异。
然而在分析光弹注入标本（图7）有人注意到不同的国家之间张力存在两种不同的类型的标本，是由于不同的模腔热传递和刚度。
这种差异解释了柔性的变化更加突出的部分晶体材料，如聚乙烯和聚酰胺6.有人注意到一个较低的柔性标本在的高密度聚乙烯分析测试管在镍核心的情况下，量化30%左右。
如尼龙6这个值也接近50%。
8 结论经过连续的测试，注塑模具在不同条件下检查的氨基磺酸镍液使用添加剂。
这就是说塑性好，硬度好和摩擦力好的层状结构，已取得的力学性能是可以接受的。
借鞋缺陷的镍壳将部分取代环氧树脂为核心的注塑模具，使注入的一系列中型塑料零部件达到可接受的质量的水平。
参考资料[1] A.E.W. Rennie, C.E. Bocking and G.R. Bennet, Electroforming of rapid prototyping mandrels for electro discharge machining electrodes, J. Mater. Process. Technol.110(2001), pp. 186–196. [2] P.K.D.V. Yarlagadda, I.P. Ilyas and P. Chrstodoulou, Development of rapid tooling for sheet metal drawing using nickel electroforming and stereo lithography processes, J. Mater. Process. Technol.111 (2001), pp. 286–294.[3] J. Hart, A. Watson, Electroforming: A largely unrecognised but expanding vital industry, Interfinish 96, 14 World Congress, Birmingham, UK, 1996.[4] M. Monzón et al., Aplicación del electroconformado en la fabricación rápida de moldes de inyección, Revista de Plásticos Modernos.84(2002), p. 557.[5] L.F. Hamilton et al., Cálculos de Química Analítica, McGraw Hill (1989).[6] E. Julve, Electrodeposición de metales, 2000 (E.J.S.).[7] A. Watson, Nickel Sulphamate Solutions, Nickel Development Institute (1989).[8] A. Watson, Additions to Sulphamate Nickel Solutions, Nickel Development Institute (1989).[9] J. Dini, Electrodeposition Materials Science of Coating and Substrates, Noyes Publications (1993).[10] J.W. Judy, Magnetic microactuators with polysilicon flexures, Masters Report, Department of EECS, University of California, Berkeley, 1994. (cap′. 3).A technical note on the characterization of electroformed nickel shells for their application to injection molds——a Universidad de Las Palmas de Gran Canaria, Departamento de Ingenieria Mecanica, SpainAbstractThe techniques of rapid prototyping and rapid tooling have been widely developed during the last years. In this article, electroforming as a procedure to make cores for plastics injection molds is analysed. Shells are obtained from models manufactured through rapid prototyping using the FDM system. The main objective is to analyze the mechanical features of electroformed nickel shells, studying different aspects related to their metallographic structure, hardness, internal stresses and possible failures, by relating these features to the parameters of production of the shells with an electroforming equipment. Finally a core was tested in an injection mold.Keywords: Electroplating; Electroforming; Microstructure; Nickel 1. IntroductionOne of the most important challenges with which modern industry comes across is to offer the consumer better products with outstanding variety and time variability (new designs). For this reason, modern industry must be more and more competitive and it has to produce with acceptable costs. There is no doubt that combining the time variable and the quality variable is not easy because they frequently condition one another; the technological advances in the productive systems are going to permit that combination to be more efficient and feasible in a way that, for example, if it is observed the evolution of the systems and techniques of plastics injection, we arrive at the conclusion that, in fact, it takes less and less time to put a new product on the market and with higher levels of quality. The manufacturing technology of rapid tooling is, in this field, one of those technological advances that makes possible the improvements in the processes of designing and manufacturing injected parts. Rapidtooling techniques are basically composed of a collection of procedures that are going to allow us to obtain a mold of plastic parts, in small or medium series, in a short period of time and with acceptable accuracy levels. Their application is not only included in the field of making plastic injected pieces [1], [2] and [3], however, it is true that it is where they have developed more and where they find the highest output.This paper is included within a wider research line where it attempts to study, define, analyze, test and propose, at an industrial level, the possibility of creating cores for injection molds starting from obtaining electroformed nickel shells, taking as an initial model a prototype made in a FDM rapid prototyping equipment.It also would have to say beforehand that the electroforming technique is not something new because its applications in the industry are countless [3], but this research work has tried to investigate to what extent and under which parameters the use of this technique in the production of rapid molds is technically feasible. All made in an accurate and systematized way of use and proposing a working method.2. Manufacturing process of an injection moldThe core is formed by a thin nickel shell that is obtained through the electroforming process, and that is filled with an epoxic resin with metallic charge during the integration in the core plate [4] This mold (Fig. 1) permits the direct manufacturing by injection of a type a multiple use specimen, as they are defined by the UNE-EN ISO 3167 standard. The purpose of this specimen is to determine the mechanical properties of a collection of materials representative industry, injected in these tools and its coMParison with the properties obtained by conventional tools.Fig. 1. Manufactured injection mold with electroformed core.The stages to obtain a core [4], according to the methodology researched in this work, are the following:(a) Design in CAD system of the desired object.(b) Model manufacturing in a rapid prototyping equipment (FDM system). The material used will be an ABS plastic.(c) Manufacturing of a nickel electroformed shell starting from the previous model that has been coated with a conductive paint beforehand (it must have electrical conductivity).(d) Removal of the shell from the model.(e) Production of the core by filling the back of the shell with epoxy resin resistant to high temperatures and with the refrigerating ducts made with copper tubes.The injection mold had two cavities, one of them was the electroformed core and the other was directly machined in the moving platen. Thus, it was obtained, with the same tool and in the same process conditions, to inject simultaneously two specimens in cavities manufactured with different technologies.3. Obtaining an electroformed shell: the equipmentElectrodeposition [5] and [6] is an electrochemical process in which a chemical change has its origin within an electrolyte when passing an electric current through it. The electrolytic bath is formed by metal salts with two submerged electrodes, an anode (nickel) and a cathode (model), through which it is made to pass an intensity coming from a DC current. When the current flows through the circuit, the metal ionspresent in the solution are transformed into atoms that are settled on the cathode creating a more or less uniform deposit layer.The plating bath used in this work is formed by nickel sulfamate [7] and [8] at a concentration of 400 ml/l, nickel chloride (10 g/l), boric acid (50 g/l), Allbrite SLA (30 cc/l) and Allbrite 703 (2 cc/l). The selection of this composition is mainly due to the type of application we intend, that is to say, injection molds, even when the injection is made with fibreglass. Nickel sulfamate allows us to obtain an acceptable level of internal stresses in the shell (the tests gave results, for different process conditions, not superior to 50 MPa and for optimum conditions around 2 MPa). Nevertheless, such level of internal pressure is also a consequence of using as an additive Allbrite SLA, which is a stress reducer constituted by derivatives of toluenesulfonamide and by formaldehyde in aqueous solution. Such additive also favours the increase of the resistance of the shell when permitting a smaller grain. Allbrite 703 is an aqueous solution of biodegradable surface-acting agents that has been utilized to reduce the risk of pitting. Nickel chloride, in spite of being harmful for the internal stresses, is added to enhance the conductivity of the solution and to favour the uniformity in the metallic distribution in the cathode. The boric acid acts as a pH buffer.The equipment used to manufacture the nickel shells tested has been as follows:• Polypropylene tank: 600 mm × 400 mm × 500 mm in size.• Three teflon resistors, each one with 800 W.• Mechanical stirring system of the cathode.• System for recirculation and filtration of t he bath formed by a pump and a polypropylene filter.• Charging rectifier. Maximum intensity in continuous 50 A and continuous current voltage between 0 and 16 V.• Titanium basket with nickel anodes (Inco S-Rounds Electrolytic Nickel) with a purity of 99%.• Gases aspiration system.Once the bath has been defined, the operative parameters that have been altered for testing different conditions of the process have been thecurrent density (between 1 and 22 A/dm2), the temperature (between 35 and 55 °C) and the pH, partially modifying the bath composition.4. Obtained hardnessOne of the most interesting conclusions obtained during the tests has been that the level of hardness of the different electroformed shells has remained at rather high and stable values. In Fig. 2, it can be observed the way in which for current density values between 2.5 and 22 A/dm2, the hardness values range from 540 and 580 HV, at pH 4 ± 0.2 and with a temperature of 45 °C. If the pH of the bath is reduced at 3.5 and the temperature is 55 °C those values are above 520 HV and below 560 HV. This feature makes the tested bath different from other conventional ones composed by nickel sulfamate, allowing to operate with a wider range of values; nevertheless, such operativity will be limited depending on other factors, such as internal stress because its variability may condition the work at certain values of pH, current density or temperature. On the other hand, the hardness of a conventional sulfamate bath is between 200–250 HV, much lower than the one obtained in the tests. It is necessary to take into account that, for an injection mold, the hardness is acceptable starting from 300 HV. Among the most usual materials for injection molds it is possible to find steel for improvement (290 HV), steel for integral hardening (520–595 HV), casehardened steel(760–800 HV), etc., in such a way that it can be observed that the hardness levels of the nickel shells would be within the medium–high range of the materials for injection molds. The objection to the low ductility of the shell is compensated in such a way with the epoxy resin filling that would follow it because this is the one responsible for holding inwardly the pressure charges of the processes of plastics injection; this is the reason why it is necessary for the shell to have a thickness as homogeneous as possible (above a minimum value) and with absence of important failures such as pitting.Fig. 2. Hardness variation with current density. pH 4 ± 0.2, T = 45 °C.5. Metallographic structureIn order to analyze the metallographic structure, the values of current density and temperature were mainly modified. The samples were analyzed in frontal section and in transversal section (perpendicular to the deposition). For achieving a convenient preparation, they were conveniently encapsulated in resin, polished and etched in different stages with a mixture of acetic acid and nitric acid. The etches are carried out at intervals of 15, 25, 40 and 50 s, after being polished again, in order to be observed afterwards in a metallographic microscope Olympus PME3-ADL 3.3×/10×.Before going on to comment the photographs shown in this article, it is necessary to say that the models used to manufacture the shells were made in a FDM rapid prototyping machine where the molten plastic material (ABS), that later solidifies, is settled layer by layer. In each layer, the extruder die leaves a thread approximately 0.15 mm in diameter which is compacted horizontal and vertically with the thread settled inmediately after. Thus, in the surface it can be observed thin lines that indicate the roads followed by the head of the machine. These lines are going to act as a reference to indicate the reproducibility level of the nickel settled. The reproducibility of the model is going to be a fundamental element to evaluate a basic aspect of injection molds: the surface texture.The tested series are indicated in Table 1.Table 1.Tested seriesSeries pH Temperature (°C)Current density (A/dm2)1 4.2 ± 0.255 2.222 3.9 ± 0.245 5.563 4.0 ± 0.24510.004 4.0 ± 0.24522.22Fig. 3 illustrates the surface of a sample of the series after the first etch. It shows the roads originated by the FDM machine, that is to say that there is a good reproducibility. It cannot be still noticed the rounded grain structure. In Fig. 4, series 2, after a second etch, it can be observed a line of the road in a way less clear than in the previous case. In Fig. 5, series 3 and 2° etch it begins to appear the rounded grain structure although it is very difficult to check the roads at thistime. Besides, the most darkened areas indicate the presence of pitting by inadequate conditions of process and bath composition.Fig. 3. Series 1 (×150), etch 1.Fig. 4. Series 2 (×300), etch 2.Fig. 5. Series 3 (×300), etch 2.This behavior indicates that, working at a low current density and a high temperature, shells with a good reproducibility of the model and with a small grain size are obtained, that is, adequate for the required application.If the analysis is carried out in a plane transversal to the deposition, it can be tested in all the samples and for all the conditions that the growth structure of the deposit is laminar (Fig. 6), what is very satisfactory to obtain a high mechanical resistance although at theexpense of a low ductibility. This quality is due, above all, to the presence of the additives used because a nickel sulfamate bath without additives normally creates a fibrous and non-laminar structure [9]. The modification until a nearly null value of the wetting agent gave as a result that the laminar structure was maintained in any case, that matter demonstrated that the determinant for such structure was the stress reducer (Allbrite SLA). On the other hand, it was also tested that the laminar structure varies according to the thickness of the layer in terms of the current density.Fig. 6. Plane transversal of series 2 (×600), etch 2.6. Internal stressesOne of the main characteristic that a shell should have for its application like an insert is to have a low level of internal stresses. Different tests at different bath temperatures and current densities were done and a measure system rested on cathode flexural tensiometer method was used.A steel testing control was used with a side fixed and the other free (160 mm length, 12.7 mm width and thickness 0.3 mm). Because the metallic deposition is only in one side the testing control has a mechanical strain (tensile or compressive stress) that allows to calculate the internal stresses. Stoney model [10] was applied and was supposed that nickel substratum thickness is enough small (3 μm) to influence, in an elastic point of view, to the strained steel part. In all the tested cases the most value of internal stress was under 50 MPa for extreme conditions and 2 MPa for optimal conditions, an acceptable value for the required application. The conclusion is that the electrolitic bath allows to work at different conditions and parameters without a significant variation of internal stresses.7. Test of the injection moldTests have been carried out with various representative thermoplastic materials such as PP, PA, HDPE and PC, and it has been analysed the properties of the injected parts such as dimensions, weight, resistance, rigidity and ductility. Mechanical properties were tested by tensile destructive tests and analysis by photoelasticity. About 500 injections were carried out on this core, remaining under conditions of withstanding many more.In general terms, important differences were not noticed between the behavior of the specimens obtained in the core and the ones from the machined cavity, for the set of the analysed materials. However in the analysis by photoelasticiy (Fig. 7) it was noticed a different tensional state between both types of specimens, basically due to differences in the heat transference and rigidity of the respective mold cavities. This difference explains the ductility variations more outstanding in the partially crystalline materials such as HDPE and PA 6.Fig. 7. Analysis by photoelasticity of injected specimens.For the case of HDPE in all the analysed tested tubes it was noticed a lower ductility in the specimens obtained in the nickel core, quantified about 30%. In the case of PA 6 this value was around 50%.8. ConclusionsAfter consecutive tests and in different conditions it has been checked that the nickel sulfamate bath, with the utilized additives has allowed to obtain nickel shells with some mechanical properties acceptable for the required application, injection molds, that is to say, good reproducibility, high level of hardness and good mechanical resistance in terms of the resultant laminar structure. The mechanical deficiencies of the nickel shell will be partially replaced by the epoxy resin that finishes shaping the core for the injection mold, allowing to inject medium series of plastic parts with acceptable quality levels.References[1] A.E.W. Rennie, C.E. Bocking and G.R. Bennet, Electroforming of rapid prototyping mandrels for electro discharge machining electrodes, J. Mater. Process. Technol.110(2001), pp. 186–196. [2] P.K.D.V. Yarlagadda, I.P. Ilyas and P. Chrstodoulou, Development of rapid tooling for sheet metal drawing using nickel electroforming and stereo lithography processes, J. Mater. Process. Technol.111 (2001), pp. 286–294.[3] J. Hart, A. Watson, Electroforming: A largely unrecognised but expanding vital industry, Interfinish 96, 14 World Congress, Birmingham, UK, 1996.[4] M. Monzón et al., Aplicación del electroconformado en la fabricación rápida de moldes de inyección, Revista de P lásticos Modernos.84(2002), p. 557.[5] L.F. Hamilton et al., Cálculos de Química Analítica, McGraw Hill (1989).[6] E. Julve, Electrodeposición de metales, 2000 (E.J.S.).[7] A. Watson, Nickel Sulphamate Solutions, Nickel Development Institute (1989).[8] A. Watson, Additions to Sulphamate Nickel Solutions, Nickel Development Institute (1989).[9] J. Dini, Electrodeposition Materials Science of Coating and Substrates, Noyes Publications (1993).[10] J.W. Judy, Magnetic microactuators with polysilicon flexures, Masters Report, Department of EECS, University of California, Berkeley, 1994. (cap′. 3).。