注射硅橡胶来提高模具的尺寸精度 外文
塑料注射模具设计系统中英文翻译
ContentsPart I Foreword ……………………………………………………… ..page 3 Part II Based on pould frame design mold…………………………… . ..page 4 Part III Minute mold module……………………………………………. ..page 7 Part IV The true fate line and goes against the direction…………………..page 8 Part V Conclusion……………………………………………………… ..page 10目录第一部分引言…………………………………………………………. ….12页第二部分基于模架设计的模具………………………………………….. 13页第三部分分模模块…………………………………………………. …….15页第四部分确定分型线和顶出方向…………………………………….. …15页第五部分结论…………………………………………………………….. 17页Plastic injection mold design system1.AbstractThe primary object of the first editeon of this book was to provide a information book on students studying in university, In addition to fulfilling this function, this book has been used increasingly by the novice as an introductory guide, because it progresses in simple stages from the consoderation of basic principles and components to mote detailed ewplanation of themore complex types of special purpose mould。
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。
The us products produced include toys。
automotive parts。
household items。
and electronic consumer goods.Because plastic n molds have many variable nships。
it is a complex and us processing process。
The success of XXX appropriate steps。
but on the XXX。
which leads to the n of XXX。
barrel temperature changes。
XXX ns can help ce tolerances。
ce defect rates。
and increase product quality.XXX operator is to produce products that e first-rate products in the shortest time。
模具制造专业外文翻译--注射成型应用
外文原文Injection Molding ApplicationsIntroductionThe use of plastic tooling in injection molding occurs within the field of Rapid Tooling (RT), which provides processes that are capable of producing injection mold tooling for low volume manufacturing at reduced costs and lead times. Such tooling allows the injection molding of parts in the end-use materials for functional prototype evaluation, short series production, and the validation of designs prior to hard tooling commitment. The term Rapid Tooling is somewhat ambiguous – its name suggests a tooling method that is simply produced quickly. However, the term is generically associated with a tooling method that in some form involves rapid prototyping technologies.Investigation and application of Stereo lithography (SL) to produce mold cavities for plastic injection molding primarily began in the 1990s. Initially the process was promoted as a quick route to soft tooling for injection molding (a tool to produce a relative low number of parts). The advantages of this have been somewhat diluted as other mold production technologies, such as high speed machining, have progressed,but other unique capabilities of the process have also been demonstrated.Stereo lithography has several process capabilities that are particularly advantageous for injection mold tooling, but we should also appreciate that is accompanied by some significant restrictions. This chapter introduces several aspects of the process accompanied by a discussion of its pros and cons, along with examples of work by different parties (Fig. 1).Fig. 1 Injection molding insert generated by stereo lithography, shown with part1. Mold ProductionIn order to discuss the main topic; the direct production of mold cavities, it is first necessary to differentiate this from the indirect route. This is not a significant topic since SL merely provides the master pattern which, irrespective of the process used to produce this, has little influence on the subsequent injection molding.1.1 Indirect Mold ProductionThe indirect methods involve the use of an initial geometry that has been produced by SL. This geometry is utilized as a pattern in a sequence of process steps that translate into a tool which may be made of a material different to that of the pattern.Cast epoxy tooling represents a common indirect plastic RT method for injection molding. The process begins with a 3D model (i.e. CAD) of the part to be molded.Subsequently this model is produced by SL to provide a master pattern around which the mold will be formed. Traditionally, the part is produced solely without provision for parting lines, gating, etc. Such ancillaries are generated by manual methods (i.e. by fixing additional features to the part). However, the advent of easier CAD manipulation allows the model to be produced including such features.Once the complete master pattern has been produced, the mold halves are created by casting epoxy around the pattern, thus recreating a negative profile of the pattern.The epoxy may include fillers in attempts to improve strength and thermal properties of the mold. Such fillers include metal and ceramic particles in various forms.1.2 Direct Mold ProductionThe direct methods involve a SL system directly generating the tooling cavityinserts in its native material. The accuracy of the SL RP process results in insertsthat require few further operations prior to their use in injection molding. Like allRP related techniques the process is dependent on a 3D CAD model of the intended geometry. Unlike indirect techniques, the whole tool insert is generated by SL and so a 3D CAD representation of the whole tool insert is required. This involves creating negatives of the part to form the mold insert bodies, plus the provisions for gating, part ejection, etc. Previously, this extra CAD work would have represented more work required in the preparation. Such input is now minimized as modern CAD manipulation packages (e.g. Materialise’s Magics software) allow the automation of such activities. Once generated, the cavity inserts need to be secured in a bolster to withstand clamping forces and to provide alignment to the mold halves.It should also be mentioned that direct SL tooling for injection molding has also been referred to as Direct AIM. This term was given to the process by 3D Systems(SL system manufacturers) and refers to Direct ACES Injection Molding. (ACES stands for “Accurate Clear Epoxy Solid,” which is a SL build style).2. The Requirement of the ProcessThe introduction of rapid prototyping has allowed engineers and designers togenerate physical models of parts very early in the design and developmentphase. However, the requirements of such prototypes have now progressed beyond the validation of geometry and onto the physical testing and proving of the parts.For such tests to be conducted, the part must be produced in the material and manner (process) that the production intent part will be. For injection molding, this situation highlights the requirement of a rapid mold-making system that can deliver these parts within time and cost boundaries.Stereo lithography provides a possible solution to this by providing the rapid creation of a mold. A negative of the part required plus gating and ejection arrangements are generated in 3D CAD to create a tool that is fabricated by SL.This provides an epoxy mold from which it is possible to produce plastic parts by injection molding.Both Luck et al. and Roberts and Ilston evaluated SL in comparison with other direct RP mold-generating techniques for producing a typical development quantity of moldings. The SLmolding process was found to be a superior alternative for producing design-intent prototypes.It has also been noted that other alternative techniques involve additional steps to the process, therefore becoming less direct and not really RT. Other advantages of the process have been highlighted beyond the prototype validation phase. Since the tool design has been verified, the lead-time and cost involved in the manufacture of production tooling is also often reduced as the tool design has already beenproven.During the early years of SL it was never envisaged that such a RT method would be possible. At first glance the application of SL for injection mold tooling seems unfeasible due to the low thermal conductivity and limited mechanical properties of epoxy, especially at high temperatures. The glass transition temperature of SL materials available was only ~60_C, while the typical temperature of an injected polymer is over 200_C. Despite these supposed limits, successful results were achieved by SL users worldwide, including the Danish Technological Institute, Ciba Geigy, Fraunhofer Institute, the Queensland Manufacturing Institute, and Xerox Corporation.3. Mold Design ConsiderationsIn terms of the mold’s actual cavity design, relatively little information exists on the specific requirements of SL tooling. The early white paper issued by 3DSystems suggests the incorporation of a generous draft angle, but does not statethe amount and recommends the use of a silicone based release agent (every shot) in an attempt to prevent the parts sticking to the inserts. Work has been conducted that quantifies the effects of draft angle on the force exerted on SL tools upon ejection of a molding. It has been shown that an increase in tooling draft angle results in a lower force required to remove a part from the tool. However, the effect of draft angle variation on ejection force is minimal and little compensation for the deviation from intended part geometry caused by the addition or removal of material required to form the draft.Work has been conducted to establish the cause of core damage during molding.This found that damage was not related to pressure, but to the size of the core features. Smaller core features were broken due to a shearing action caused by polymer melt movement.Experimentation has revealed two modes of wear during the material flow within the cavity. These modes were abrasive at medium flow points (i.e. sharp corners),and ablative at highflow points (i.e. injection points). Other work has also emphasized the importance of the material flow influenced by mold design, identifying gating, and parting line shut off areas as points of potentially high wear.Fig. 2 Parts requiring different gating arrangements according to molding material4. injectionlaser system’s degree of curing is dependent upon the pulse frequency and the hatch spacing. Generally a continuous mode laser system allows for greater energy exposure.With respect to post-curing operations it should be noted that the amount of curing is not greatly affected by UV environment exposure. If thermal post curing is tobe used it should also be noted that a large majority of warpage occurs during this stage, which may be a concern if thin walled sections are in existence.The layer thickness of each build slice dictates the SL part’s roughness on surfaces parallel to the build direction. When this surface roughness is parallel to a mo lded part’s direction of ejection it has a resultant effect on the force required to remove the part from the mold which in turn applies a force to the insert which could result in damage. This surface roughness and the ejection forces experienced,correspond linearly to the build layer thickness. The solution is to re-orientate the SL build direction or employ a lesser layer thickness.4.1 Injection MoldingDuring molding, a release agent should be frequently used to lower the force experienced by the too l due to part ejection. In the author’s experience, a siliconelike agent is the most successful. Low-injection pressures and speeds should be used whenever feasible. Much lower settings are feasible in comparison to some forms of metal tooling due to SL heat transfer characteristics as discussed within this section.Early recommendations for SL injection molding stated that since damage occurs during part ejection it was appropriate to allow as much cooling prior to mold opening as possible. This reduced the tendency of the parts to stick to the inserts . The author has trialled this approach, which often leads to greater success, but the part-to-part cycle times are extremely long.More recent work has demonstrated that it is advantageous to eject the part as soon as possible (when part strength allows) before the bulk mass of cavity features have exceeded their glass transition point, when their physical strength is greatly reduced. This greatly reduces the heat transmitted into the tool and the cycle time for each part. Subsequently, it is also critical to monitor the mold temperature throughout the molding cycle to avoid exceeding the glass transition temperature (Tg) of epoxy, where tool strength is reduced. This entails each molding cycle beginning with the epoxy insert at ambient temperature and the part being ejected prior to Tg of the majority of the inserts volume being reached. This has been achieved in practice by inserting thermocouples from the rear of the cavity insert into the most vulnerable mold features such that the probe lies shortly beneath the cavity surface. Allowing the polymer to remain for sufficient time within the mold, while also avoiding critical Tg, is possible due to the very low thermal conductivity of SL materials.In addition, the low thermal conductivity of SL materials has been demonstrated to be advantageous in this application for injection mold tooling. It has been shown that the low thermal conductivity of SL tooling allows the use of low injection speeds and temperatures which are required due to the limited mechanical properties of SL materials. Traditional metal tooling needs these high pressures and speeds to prevent the injected polymer freezing prior to the mold completely filling.This is due to the rapid cooling of the injection melt when it comes into contact with the high thermal conductivity mold surface. Also, the SL tooling process has shown itself to be capable of producing parts that would not be possible under the same conditions using a metalmold. The thermal characteristics of SL tooling have made it possible to completely mold crystalline polyether ether ketone (PEEK), which has an injection temperature of 400_C (752_F).An equivalent steel mold would require a premolding temperature of about 200_C(392_F). An impeller geometry was successfully molded with vastly lower injection speeds and pressures were utilized, as shown in the Table 1 and Fig. 3.Table 10.1 Polyether ether ketone molding variables in SL mold vs. steel moldFig. 3 PEEK impeller molded by stereo lithography toolsA particularly illustrative account of the cooling conditions is shown in the above image. It can be seen that the polymer is primarily gray in color where it contacts SL surfaces indicating crystalline formation. Whereas where it comes into contact with the steel ejector pins it is brown, indicating localized amorphous areas. This is due to the difference in heat transfer of the two materials and hence the cooling rate experienced by the contacting polymer.5. Process ConsiderationsVarious polymers have been successfully molded by SL injection molding. These include polyester, polypropylene (PP), polystyrene (PS), polyamide (PA), polycarbonate,PEEK, acrylonitrile styrene acrylate, and acrylonitrile butadiene styrene.The greatest material limitation encountered has been the use of glass filled materials. All evidence indicates that the SL molding technique does not cope well with glass filled materials due to severe problems of abrasion to the SL cavity surface. This leads to poor quality, inaccurate parts, and undercuts in the cavity, which eventually result in the destruction of the SL insert. This abrasive nature has been quantified with a comparative SL molding study of PA 66 and PA 66 with 30% glass fiber content. The PA 66 enabled 19 shots prior to damage, while the glass filled variant allowed only 6 shots before the same level of damage was incurred . These findings are supported by work conducted by the author, with PA 66 with a 30% glass fiber content inducing high mold wear. However, it has been demonstrated that appropriate choices in mold design and process variables reduced the rate of wear. The use of appropriate settings has allowed the successful molding of a low number of partsas large as 165 _ 400 _ 48 mm (6.5 _ 16 _ 2 in.) with high geometrical complexity in PA66 with 30% glass content. The tool and parts are shown in Figs. 4 and 5.6 .Molded Part PropertiesDuring the course of my work with SL tooling, I have endeavored to investigate and pursue the most important aspect of tooling and molding; it is a means to an end.The end is the molded parts themselves. These are the products and if they are unsuitable, then tool performance is entirely irrelevant. Early work examining the resultant parts produced by the SL injection process described them only as being of a poor quality, effected by warping, and requiring a longer time to solidify due to the mold’s poor heat transfer producing a nonuniform temperature distribution. Other work also noted that using diffe ring materials in a mold’s construction (i.e. a steel core and a SL cavity) led to warping of the part due to the different thermal conductivities of the mold materials .Fig. 4 Large stereolithography molding toolFig. 5 Subsequent parts produced in polyamide 66 (30% glass fiber) The low thermal conductivity, and hence the low cooling rate, of the mold has a significant influence on the material properties of the molded parts. It was shown that parts from an epoxy mold exhibit a higher strength, but a lower elongation;around 20% in both cases .The differing mechanical properties of parts produced from SL molds as compared to thosefrom metal tools is also demonstrated in other work . This showed that the parts manufactured by SL molding had a lesser value of Young’s Modulus compared to those produced in a steel mold but possessed a greater maximum tensile strength and percentage elongation at break. These different part properties were attributed to a slow rate of heat transfer of the tool. This slow rate of heat transfer produces longer part cooling times giving a greater strength but less toughness.Research performed at Georgia Institute of Technology further investigated the mechanical properties of parts produced by the SL molding process. This work showed that noncrystalline and crystalline thermoplastic parts produced by the SL molding technique displayed differing mechanical characteristics than parts from traditional molds. Noncrystalline material parts possessed similar all-round mechanical properties compared to those produced in identical steel molds. However, crystalline thermoplastic parts demonstrated higher tensile strength, higher flexural strength, and lower impact properties compared to those manufactured in identical steel molds. More so with crystalline polymers than with amorphous materials, the mechanical properties of the plastic parts are influenced by the cooling conditions. These differing effects on mechanical properties have been demonstrated with PS (amorphous) and PP (crystal line). When the respective part’s mechanical properties were compared when produced by steel and by SL molds, the PS parts showed very little change while the PP parts demonstrated a great difference . In addition to differences in mechanical properties it has also been identified that some polymers exhibit different shrinkage according to the cooling conditions of the part during molding. These works indicate that crystalline polymers are susceptible to greater shrinkage when subjected to a slow cooling time.These differences in part properties have been attributed to the degree of crystallinity developed in the molded parts. This has been demonstrated by microscopic comparisons of parts produced by SL and metal alloy tooling. This revealed the spherulites (a crystal structure consisting of a round mass of radiating crystals) to be considerably larger from the SL tooling parts due to the higher temperatures and slower cooling involved during molding.In the wider field of general injection molding and plastics research, work has been conducted to identify and assess the variables that influence parts properties. These papers report a common theme, they identify the thermal history of the part to be a critical variable responsible for the parts resulting attributes. Recent work has shown that the slower molded part cooling imposed by SL tooling provides an opportunity to make some variations in the molding parameters for crystallinepolymers which allow the control of critical morphological factors (level of crystallinity). The subsequent level of crystallinity dictates many of the resultant part properties. The process modifications in this work were realized without changes to the machine, tool, or molded material (i.e. external cooling control, different polym er etc). This demonstrates a possible “tailoring” of molded part properties that would allow certain desirable part properties to be altered.These revelations demonstrate an advantage of SL tooling that was shown to not be possible in metal tooling. In summary, we must consider that the thermal characteristics of SL molds have an influence on the morphological structure of some parts. This may lead to a difference in the morphology of parts from SL tools as compared to those from metal tools. Such morphological differences can affect the shrinkage and mechanical properties of the molded part. When using SL tooling, one must decide if these differences are critical to the functionality of the part.7. ConclusionIn conclusion, SL molding is a viable process for some, but by no means all,injection molding tooling applications. Most important, is that the user should beinformed of the alternate design and processing requirements compared to conventional tooling, and be aware of the difference in resultant part characteristics, thus enabling realistic expectations and a more assured project outcome.注射成型应用摘要在快速成型领域中塑料模具在注塑成型时的应用，它在生产过程中可以制造出小批量生产降低成本和缩短时间的注塑模具。
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。
英文翻译(精密注射成型技术进展)
英文原文：P recision injection molding technology of progressusing precision injection molding machine to replace conventional injection molding machinePrecision injection molding machine generally larger injection power, in addition to such injection pressure and injection to meet the requirements in terms of speed, power itself will be on the injection products improve the accuracy of a certain role. Precision injection molding machine control systems generally have high control precision, it is requested by the products themselves. High accuracy can be guaranteed control of injection process parameters has good accuracy, precision products in order to avoid fluctuations due process parameters change. Therefore precision injection molding machine generally of the injection, injection pressure, injection rate and pressure-pressure, back-pressure and screw speed process parameters such as a multi-level feedback control. Precision Injection requirements of its modulus system has sufficient rigidity, accuracy or products will be a model for the elastic deformation decreased. Second-Die-Die of the system must be able to accurately control the size, or too large or too small a model of precision products will have an adverse impact. So in the design, it should be considered Die rigidity, stiffness, as well as a model system in order to accurately control the size of the precision products, especially flat-panel thin-wall products. When Die larger, must-oriented column deflection check. Precision injection molding machine also must be able to work in the hydraulic circuit precise temperature control, work to prevent the oil due to temperature changes caused viscosity and flow changes, further injection process parameters leading to fluctuations而使products would lose their accuracy.1. parts molding cycle time consistencyGeneral typical injection molding machine with three modes: manual, semi-automatic and fully automatic. As the influence of various factors, each of the previous two models molding cycle time may be different, it would affect the temperature and materials to die in the Liaodong stay, thereby affecting the accuracy of parts, in precision Molding should try to use the automatic mode.2. precision injection molding machine screw temperature control and the design of newInjection Molding Machine cylinder automatic thermostat on the cycle of opening and customs led to the Liaodong, melting material density and viscosity changes, thereby affecting the quality and dimensional accuracy of parts of the cyclical fluctuations in the injection molding machine nozzle close to Die Therefore, the temperature of the nozzle molded parts also have a significant impact on. Modern injection molding machine equipped with a special process control software to control temperature fluctuation, which is proportional integral differential (P ID) control. At least from the barrel temperature difference galvanic point perspective, the P ID parameter optimization can completely eliminate temperature fluctuations.To the quality and stability of the plastic parts, plastics injection molding machine unit is very important. To the plastics unit is an important standard to judge: injection volume, plastics rate, injection rate, the polymers in the plastics unit at the time.As the quality of plastic parts for the dimensional accuracy error of a very important impact, and it should be precise injection control of the injection molding machine. Improve measurement precision injection molding machine of the most effective ways is to use technology to achieve the smallest screw diameter, especially for the light parts especially. The measurement of the relative screw length and the overall length of screw smaller, in the plastics materials unit at the time also become shorter. Screw thread is similar to widening the materials can be avoided stay longer so that the screw and stable operation. Lo deep groove width than correspondingly smaller, which create a lot of engineering plastics parts of the small diameter screw particularly effective. Melt homogeneity and are not small compression ratio decreases, it is because from the very shallow groove Lo caused very strong result of the shear rate. Feeding the difficulty of the design, it must ensure that all aggregates can be fed into evenly. Considering the need to shorter cycles, plastics rate must also be big enough, in the design of the feed must be effectively resolved the contradiction between. In addition, if adopted by a two-stage injection screw to achieve precise control injection error, which requires the measurement of the melt through spherical valve detected by injection to injection molding machine in the Detroit injection molding machine.Before microprocessor controlled by the injection molding process can not be obtained through injection precision voltage comparator has been successfully resolved. V oltagecomparator allows Transmitter and other sensitive came with the very precise voltage signal passed, and when the set point appears to be following the true value of a timely signal immediately transmitted to the microprocessor control of the order, by order of the cycle of operational procedures Asynchronous from time to time through a direct transfer of the signal process to eliminate, greatly improving the control accuracy.precision molding technology1. In the mold injection-compression molding applications (ICM) technologyICM technology is the means to open a certain distance die under the conditions of the beginning injection, injection to a certain amount, the mold cavity beginning of the closure of the melt compression, injection mold completely closed at the termination, and then packing, cooling until the removal products. Through injection-compression molding of compression products to compaction, making products on the surface of uniform pressure distribution, the compaction products such size high accuracy and stability, small deformation. It is in the mould open circumstances melt into the cavity and, therefore, mobile channel, for the low pressure injection molding, and reduce or eliminate the pressure caused by the resin-molecular orientation of the stress and products, which improve products, dimensional stability. ICM technology and flexible control capability than the injection mould has greatly improved. Therefore use of this technology can produce more precision parts, especially the high-precision cylindrical-shaped parts.2. High-speed injection moldingHigh-speed injection molding method of filling melts faster rate than the traditional 10 to 100 times, melt in the mold cavity to produce high shear flow, decrease viscosity, injection speed, slow down plastic surface hardening, thus improving thin Forming products wall thickness limit, inhibit excessive molding pressure, as well as because of the low-voltage mobile mode, the products reduce stress. The thin-wall precision products, we can use the injection screw at the forward from the melt energy absorption in the screw after the cessation of movement through the expansion of high-speed melt full cavity to achieve.3. No-pressure injection moldingNo-pressure injection molding technology refers to the plastic melt high-speed, high-pressure filling into the mold, and then close in the nozzle needle to melt the plastic mold cavity products automatically compensate for different parts of the contract, such products can be greatly reduced warpage. However, this method requires prior estimate packing contraction added, hence the need for the injection of a higher cavity pressure value, and we need clamping force also high.4. Other Intelligent Control TechnologyPrecision injection molding processing conditions in the process of continuous monitoring and implementation of precise control is very important. With the development of computer technology, computerized injection molding has been widely used. Among them, statistical process control (SPC), P ID technology, fuzzy logic control (FCC), network control center (NNC) method and the processing model based on the reverse of the backbone network size control.Advantages1.High production rates. For example, a CD disk can be produced with a 10-12scycle in high melt flow index PC.2.Relatively low labor conent. One operator can frequently take care of two or moremachines, particularly if the moldings are unloaded automatically onto conveyors.3.Parts require little or no finishing. For example, flash can be minimized and moldscam be arramged to automatically separate runners and gates from the part itself.4.Very complex shapes can be formed. Advances in mold tooling are largelyresponsible.5.Flexibility of design ( finishes, colors, inserts, materials ). More than one materialcan be molded through co-injection. Foam core materials with solid skins areefficiently produced. Thermosetting plastics and fiber-reinforced shapes areinjection molded.6.Minimum scrap loss. Runners, gates, and scrap can usually be reground. Recycledthermoplastics can be injection molded.7.Close tolerances are obtainable. Modem microprocessor controls, fitted toprecision molds, and elaborate hydraufics, facilitate tolerances in the 0. 1% rangeon dimensions and weights ( but not without a high level of operational skills inconstant attendance).8.Makes best use of the unique attributes of polymers, such as flow ability, lightweight, transparency, and corrosion resistance. This is evident from the numberand variety of molded plastic products in everyday use.Disadvantages and Problems1.High investment in equipment and tools requires high production volumes.ck of expertise and good preventive maintenance can cause high startup andrunning costs.3.Quality is sometimes difficult to determine immediately. For example, plst-moldwarpage may render parts unusable because of dimensional changes that are not completed for weeks or months after molding.4.Attention is required on many details requiring a wide variety of skills andcross-disciplinary konwledge.5.Part design sometimes is not well suited to efficien molding.6.Lead time for mold desin, mold manufacture and debugging trials is sometimes verylong.ConclusionOn the high-precision plastic products, and high-performance requirements of the growing precision injection molding technology is the impetus for moving forward, people on the principle of precision injection molding, the constant deepening of understanding of precision injection molding technology is the basis for progress. With new materials, new processes and new equipment has emerged, particularly in the plastics processing computer is the wide application of the precision injection technology to create goodconditions. As long as a reasonable use of these technologies, we will be able to produce sophisticated products.中文对照：精密注射成型技术进展采用精密注塑成型机，以取代传统的注塑机精密注塑机注射功率一般较大，除了注射压力和注射速度满足要求外，电源本身将是提高注塑产品精度的以个重要角色。
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。
模具注射成型中英文对照外文翻译文献
中英文对照资料外文翻译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)themachine 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 uniton which the stationary section of the mold is bolted .This member 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 when it 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 arisesbecause the densities of polymers change so markedly with temperature 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 coresare mounted. The mold ,which contains one or more cavities,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。
花洒注塑模具设计外文翻译
注塑模具设计系统Ng Chuan Huat, Lim Bam Soon and Sulaiman Hassan1Manufacturing & Industry Engineering Department, Faculty of Mechanical &Manufacturing EngineeringKolej Universiti Teknologi Tun Hussein Onn, Beg Berkunci 10186400 Batu Pahat, Johor Malaysiaahuat@.my, sulaiman@.my摘要如今，市场对金属铸件产品的时间越来越短，因此所需的时间可用于制作蜡注塑模具正在减少。
那里省时可能是在模具设计阶段。
本文提出了一种基于交互式知识蜡注塑模具设计系统的基本结构。
该系统的基本源于蜡注塑模具设计过程中模具设计公司的分析。
这种蜡注塑模具设计系统涵盖了模具设计过程和模具基地标准化。
在这个系统中，图形模块和用于产生模制特征的基础知识模块被交互式模具向导平台，Unigraphics的系统内集成。
这确保了加快蜡注塑模具的设计过程中，而不需要重新设计模具基体布局。
有了这个功能，金属铸造产品可以快速设计，便宜的质量和竞争力。
关键词：蜡注塑模具;标准化的模板;模板向导;UG1.0 引言当今，模具设计是整个设计过程的关键，需要知识，技能，最重要的是在该领域的经验。
另一方面，模具的设计过程仍然在实行“试错”的方法。
不过，该方法被认为是需要消费大量的设计处理时间。
因此，制造商希望通过自动化的设计过程缩短设计和制造时间。
对于非常有限的产量以高的生产程序的开发，型态的投资成型可从消耗性材料进行机械加工，通常是塑料的，例如聚苯乙烯。
当需要大量的铸造件时，该模式是通过注射消耗成蜡铸造或机加工模式成型模具生产。
这些模具的尺寸公差是紧密控制。
注塑模具设计对产品质量和高效的产品加工至关重要。
中英文翻译模板-注射成型技术以及住塑优化经典资料
Injection mold design and the new-type injekt by shaping technologeThe plastic injection mold is in the present all plastics mold，uses the broadest mold, can take shape the complex high accuracy，plastic product. Under only is sketchily introduces.The design plastic injection mold first must have the certain，understanding to the plastic, the plastic principal constituent is a polymer. Like we often said the ABS plastic then is the propylene nitrile, the pyprolylene, the styrene three kind of monomers uses the emulsion, the main body or aerosol gathers the legitimate production,enable it to have three kind of monomers the high performance and may the compression molding, injects under the certain temperature and the pressure to the mold cavity, has the flow distortion, the obtaining cavity shape, after guarantees presses cooling to go against becomes the plastic product. The polymer member assumes the chain shape structure generally, the linear molecule chain and a chain molecule thought is the thermoplastic, may heat up the cooling processing repeatedly, but passes through heats up many members to occur hands over the association response, including forms netted the build molecular structure plastic usually is this, cannot duplicate injects the processing, also is the thermosetting plastics which said.Since is the chain shape structure, that plastic when processing contracts the direction also is with the polymer molecular chain under the stress function the orientation and the cooling contraction related, must be more than in the flow direction contraction its vertical direction in contraction. The product contraction also with the product shape, therunner, the temperature,guarantees presses factor and so on time and internal stress concerns.In the usual book provides the shrinkage scope is broad, considers is product wall thickness, the structure and the determination casts the temperature pressure size when the practical application and the orientation. The common product if does not have the core strut, the contraction correspondingly wants big. The plastic casts the mold basically to divide into the static mold and to move the mold. Injection Molding . Injection molding is principally used for the production of thermolplastic part ,although some progress has been made in developing a method for injection molding some thermosetting materials .The problem of injecting a melted plastic into a mold cavity from a reservoir of melted material has been extremely difficult to solve for thermosetting plastics which cure and harden under such conditions within a few minutes 。
硅橡胶印模材料ExpressTMVinylPolysiloxaneImpressionMaterial
硅橡胶印模材料Express TM Vinyl Polysiloxane Impression Material使用说明【规格型号】本使用说明涵盖以下规格型号：硅橡胶印模材料–托盘型(Express™ STD Vinyl Polysiloxane Impression Material Putty)（以下用“7312”代替）硅橡胶印模材料–补充装(Express™ Vinyl Polysiloxane Impression Material Light Body Regular Set)（以下用“7302”代替）硅橡胶印模材料–套装(Express™ Vinyl Polysiloxane Impression Material Introductory Kit)（以下用“7300”代替）【适应症】供口腔科牙齿修复时取模用。
【性能结构及组成】本产品主要由本剂和催化剂组成，主要成分为乙烯聚基二甲基硅氧烷、染色剂。
主要性能：线性尺寸变化小于1.5，弹性回复率大于96.5%。
【使用方法】选择本产品是为制作精确的牙冠及牙桥，义齿及咬合记录印模而设计的乙烯聚甲基硅氧烷牙科印模材料。
Express TM印模材料提供以下不同粘度及固化时间：●硅橡胶印模材料–补充装 (7302)●硅橡胶印模材料 - 托盘型 (7312)* 经过15秒的口内注射充填时间** 经过30秒的油泥混合时间总工作时间自口内取出时间7302 常规固化@23°C (73°F) = 90 秒 5.0 分钟低粘度@37°C (95°F) = 60 秒 5.0 分钟7312 托盘型@23°C (73°F) = 90 秒 5.0 分钟在口内注射开始后，牙托必须在规定时间内安置完成（7302为60秒）。
搅拌完成后，7312必须在60秒内安置完成。
无论耗费多久操作时间，一旦牙托安置完成，7302及7312则需要5分钟的固化时间。
模具DFM常用中英文对照
DFM常用中英文对照15、如果分型面此处，模具上会有尖角和刀口，对模具寿命有影响。
There are sharp edges if we set the parting line here, it will reduce the tool life.16、此处料厚段差很大，成品表面会有应力痕，建议修改如图示。
The thickness is not equal and it will bring the stress lines on the surface, suggest to improve the part as the picture shown.17、此大行位上有小行位，开模时小行位需先退，大行位做延时，合模时则相反。
The small slider is inside the big slider, when the mold open, the small slider need to recede first and the big slider have to postpone. When the mold close, it is contrary.18、此处需做强顶。
This position need to force ejection.19、由于此处没有足够空间下热咀，所以需做一个柱子进胶。
This position need to make a pole for gating because there have no enough space for hot sprue.20、沾模，Stick1.High shrinkage values could indicate sink marks or voids at gate location 高缩水率的产品容易产生缩印，但在浇口附近可以避免。
2.Welding line on the cosmetic surface 熔接线在外表面3.Two banana gate was to being confluent in the end of melt flow. 两个香蕉浇口在流动未端熔合。
注射成型外文文献翻译、塑料模具类外文翻译、中英文翻译
2.3注射成型2.31注射成型注塑主要用于生产热塑性塑料零件，也是最原始的方法之一。
目前注塑占所有塑料树脂消费量的30%。
典型的注塑成型产品“塑料杯、容器、外壳、工具手柄、旋钮、电气和通信组件(如电话接收器)、玩具、和水暖配件。
聚合物熔体由于其分子量具有很高的粘度；它们不能像金属液在重力的条件下倒进模,必须在高压力下注入模具。
因此,金属铸造的力学性能是由模具壁传热的速度决定，同时也决定了在最终铸件的晶粒尺寸和晶粒取向, 高压注射成型过程中熔体的注射剪切力产生的主要原因是材料最后的分子取向。
力学性能影响成品都是因为在模具里的注塑条件很冷却条件。
注塑已应用于热塑性塑料和热固性材料,发泡部分,也已被修改过用于展现注射成型（RIM）反应过程，其中有两个部分组成，一种是热固性树脂体系，另一种是聚合物快速注射模具。
然而大多数注射成型是热塑性塑料,后面的讨论集中于这样的模型。
一个典型的注塑周期或序列由五个阶段组成(见图2 - 1):注射或模具填充;(2) 包装或压缩;(3) 保持;(4) 冷却;(5)部分排除物图2 - 1注射成型过程塑料颗粒（或粉末）被装入进料斗并通过注塑缸上的开口在那里它们被旋转螺杆结转。
螺杆的旋转使颗粒处于高压下加上受热缸壁使它们融化。
加热温度范围从265到500°F。
随着压力的增大,旋转螺丝被迫向后,直到积累了足够的塑料可以进行注射。
注射活塞(或螺钉)迫使熔融塑料从料桶通过喷嘴、浇口和流道系统,最后进入模腔。
在注射过程中,熔融塑料充满模具型腔。
当塑料接触冷模具表面,它迅速凝固(冻结)产生皮肤层。
由于核心仍在熔融状态,塑料流经核心来完成填充。
一般的，该空腔被注入期间填充到95％?98％。
然后成型工艺转向了填充的阶段。
型腔填充后，熔融塑料开始冷却。
由于冷却塑料会收缩产生缺陷，如缩孔、气泡，而且空间存在不稳定性。
所以被迫实行空穴用来补偿收缩、添加塑料。
一旦模腔被填充，压力应用熔体防止腔内熔融塑料会流进浇口。
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。
tpsiv注塑成型工艺
tpsiv注塑成型工艺TPSIV注塑成型工艺是一种常用的塑料成型工艺，主要用于生产各种复杂形状的塑料制品。
本文将为大家介绍TPSIV注塑成型工艺的原理、工艺流程、优点和应用领域。
一、TPSIV注塑成型工艺的原理TPSIV（Thermoplastic Silicone Vulcanisate）是一种热塑性硅橡胶材料，通过注塑成型工艺将其加热熔融后注入模具中，经冷却固化后得到所需的塑料制品。
TPSIV注塑成型工艺的原理是利用热塑性硅橡胶在高温下可熔融流动的特性，通过模具的开合和注射系统的控制，将熔融的TPSIV材料注入模具中，经过一定的冷却时间后，模具开启，取出成品。
二、TPSIV注塑成型工艺的工艺流程1. 模具准备：根据产品的形状和尺寸，设计和制造注塑模具。
2. 原料准备：选择合适的TPSIV材料，并按照一定的配方将其加工成颗粒状。
3. 加热熔融：将TPSIV颗粒加入注塑机的料斗中，通过加热系统将其加热熔化，使其成为可流动的熔融状态。
4. 注塑成型：将熔融的TPSIV材料注入模具中，通过注射系统的控制，使其充满整个模具腔道，并保持一定的压力和注射时间。
5. 冷却固化：在模具中冷却一定的时间，使TPSIV材料完全固化。
6. 模具开启：当TPSIV材料固化后，打开模具，取出成品。
7. 后处理：对成品进行必要的修整、清洁和包装。
三、TPSIV注塑成型工艺的优点1. 成型周期短：TPSIV材料具有良好的流动性和熔融性，注塑成型工艺可以快速完成产品的成型，提高生产效率。
2. 高精度：注塑成型工艺可以制造出形状复杂、尺寸精确的塑料制品，满足不同行业的需求。
3. 产品质量稳定：TPSIV材料具有优异的物理性能和化学稳定性，注塑成型工艺可以保证产品质量的一致性和稳定性。
4. 生产成本低：TPSIV注塑成型工艺无需额外的后续加工工艺，可以节省生产成本。
四、TPSIV注塑成型工艺的应用领域1. 汽车行业：TPSIV材料具有良好的耐高温、耐油性能，常用于汽车密封件、导管等零部件的制造。
机械 模具 外文翻译 外文文献 英文文献 注射硅橡胶来提高模具的尺寸精度
注射硅橡胶来提高模具的尺寸精度P邓恩和G伯恩机械工程学系，工程学院，都柏林大学，爱尔兰共和国摘要：快速原型系统固有的技术局限性导致发展快速制模技术。
这些技术是生产材料原型能力预期的制造过程。
一个快速模具制造过程，提供了一个低成本，快速的注射成型热塑性增强硅元件制造成型。
在成型周期的压力和温度下的研究模具变形情况和组件生产遭受损失的尺寸精度。
以分析和实验研究进行了量化的尺寸精度，由过程中产生的成分，确定成型参数，有助于减少对尺寸精度的损失。
模具在各种成型条件中制作一个立体主从模式和用于高冲击聚苯乙烯注塑模具零件。
模压部件生产是典型的与一对超大的尺寸精度损失为0.3 ± 0.6毫米。
两个参数，即注射压力和模具温度等发现有一对尺寸精度的影响。
注射压力会使模腔扩大零部件制造的结果是超大的。
在一个组件注射压16MPa产生的平均值0.34毫米（1.3百分之）宽过大，0.36毫米（百分之11.3）在深度过大。
这些在一个生产注射压力20MPa的情况下产生平均的0.45特大（百分之1.8）宽度和0.59毫米（百分之18.6）的深度，由于模具温度的升高导致模具型腔尺寸减少，这是因为橡胶模具是在一个受限制金属模架。
橡胶模具扩展到腔自由空间，组件在50，70和90°的生产模具温度在以平均过大宽度分别为0.37毫米（百分之1.5），0.34毫米（百分之1.3）和0.20（百分之0.8）。
关键词：真空铸造，快速模具，模具硅胶符号d 深度（毫米）D 宽度（毫米）w 浇口距离（毫米）1简介喷射注塑材料和工业的快速发展让业内人士设计和制造的组件越来越复杂[1]。
与之相关的组件都是用一样的复杂的模具制造的精度要求。
因此,设计制造和生产注塑模具都是费时而且价格昂贵。
因此,重要的评价进行构件设计彻底关于性能和制造生产加工昂贵的承诺之前[2]。
通常该评估值得指的是制造取得的原型组件。
在此领域的产品设计,该术语原型一般指物理模型体现了一些或所有的元素的一种产品。
模具设计与制造专业外文翻译--气辅注射成型
外文原文：Gas-Assisted Injection MoldingInjection molding is a very popular operation for production of commercial plastic parts with its sophisticated control and superior surface details. However, it has limitations, such as long cycle time for parts with thick sections due to slow cooling. Also packing of thick sections can produce sink marks on the part surface. Large thin parts can have warpage because the residual stress and strain induced during filling and packing. Thus traditional injection molding can be modified to solve these kinds of problems, also to improve the quality of the part and lower the cost of production.Currently, gas-assisted injection molding is in use and being developed worldwide. In the US, the process is known as Gas-Assisted Injection Molding (GAIM); it is also called Gas Injection Technique (GIT) in Europe (see Fig.4.3.1). This process is developed for the production of hollow plastic parts with separate internal channels. It is unique because it combines the advantages of conventional injection molding and blow molding while differing from both. GAIM offers a cost effective means of producing large, smooth surfaced and rigid parts using lower clamping pressure with little or no finishing. By introducing the gas before complete filling, numerous problems such as warpage, sink marks, and high filling pressure are mostly overcome. Moreover, the process gives great benefits in terms of higher stiffness-to-weight ratio than the solid parts with the same overall dimensions due to the elimination of material placed inefficiently near the neutral axis of the cross section, thus increasing the freedom of part design.In comparison with conventional injection molding, the gas-assisted process is more critical in terms of process control, especially for multi-cavity applications. The quality of the part is determined by both tool and process variables such as degree of under-fill, gas injection conditions, and mold temperature, thus indicating the importance of process control. The process is attracting many molders due to the demand for highly automated production of gas-assisted injection molded parts.The gas-assisted injection molding process is the most rapidly growing fieldwith considerable work going on in the field of controls and the process development. Research interest is drawn towards the development of new gas injection units, the study of the process variable, the efficiency of the production process, and advantages offered by the new process. Many different companies are offering gas injection-molding units with the various options, which are mainly pressure controlled or volume controlled processes.In gas injection molding, the mold is partially filled with molten thermoplastic, and an inert gas, usually nitrogen, is injected into the plastic. Gas is injected into the molten thermoplastic material using either of two procedures. In one method, a measured volume of gas is pressurized in a container. A valve is opened to allow the gas to flow into the polymer, and a piston is activated to force all gas from the container into the mold. As the gas expands in the mold, its pressure drops. A second method holds gas pressure, rather than gas volume, constant. The gas rapidly travels down the thickest-and therefore the hottest-section of the part, advancing the melt front and filling and packing the mold. Additional plastic volume may be displaced by the pressurized gas as the material shrinks. After the plastic cools, the gas is allowed to escape, leaving a molded plastic part containing internal voids.The standard GAIM process can be divided into four partial steps. The first step is a stage of melts injection [Fig.4.3.2 (a)]. The cavity is partially filled with a defined amount of melt. The required volume is empirically determined by performing filling studies in order to avoid blowing the gas through at the flow front and to ensure an ideal blowhole volume. Typically the polymer fills thecavity between 75%~95% before the meltand gas transition.The gas inlet phase is the second stage,which is shown in Fig. 4. 3. 2(b). Gas maybe added at any point in time either duringor shortly after melts injection. The gas canenter only if the gas pressure exceeds themelt pressured. In the interior of the moldedpart, the gas expels the melt from the plasticnucleus until the remainder of the cavity iscompletely filled. Gas injection pressuresrange from 0.5~30Mpa (70~4500psi).At the gas holding pressure phase, [Fig.4.3.2(c)] the gas continues to push thepolymer melt into the extremities of thecavity of the molded article acts as a holdingpressure to compensate for path of leastresistance as it pushes through the polymer.The final stage is a gas return for recycling or a gas release to atmosphere [Fig.4. 3. 2 (d)]. After the gas holding phase, the gas pressure in the molded article is released to the outside by suitable gas return and/ or by pressure release.A. Advantages of the GAIM processGas injection provides a solution to a number of problemsthat occurs in conventional injection molding.(1) Reducing stress and warpageWith gas, the pressure is equal everywhere throughout the continuous network of hollow channels. When designed properly, these provide an internal runner system within the part, enabling the applied pressure, and therefore the internal stress gradients, to be reduced markedly. This reduces a part’s tendency to warp.(2) Elimination of sink marksSink marks resulting from ribs or bosses on the backside of a part have long been a problem. These surface marks result from the volume contraction of the melt during cooling. Sink marks can be minimized or eliminated if a hollow gas channel can be directed between the front surface of the part and the backside detail. With gas injection, the base of the rib made somewhat thicker to help direct the gas channel. With a gas channel at the base of a rib, material shrinks are away from the inside surface of the channel as the molded part cools because the material is the hottest at the center. Therefore, no sink mark occurs on the outside surface as the part shrinks during cooling.(3) Smooth surfaceUnlike structural foam, gas injection permits lighter weight and saves material ina structurally rigid part. With gas holding, a good surface quality can be achieved.(4) Reduced clamp tonnageIn conventional injection, the highest pressure occurs during the packing phase. The maximum injection pressure is significantly lower in GAIM and a controlled gas pressure through a network of hollow channels is used to fill out the mold. This means that clamp tonnage requirements can be reduced by as much as 90%.(5) Elimination of external runnersOne of the best features of gas injection is that flow runners can be built right into the part. Frequently, all external runners (both hot and cold) can be eliminated, even on a larger and complex part. These benefits include the reduced tooling costs, the lower quantities of regrind from runners, and the improvement of temperature control over the plastic melt. Often the internal runners can improve the flow pattern in the mold and eliminate or control knit-line location resulting from multiple injections from multiple injection gates. In addition to serving as flow channels, the ribs and thick sections can provide structural rigidity when required.(6)Permitting different wall thicknessA constant wall thickness is maintained in the plastic parts. With gas injection, this design rule is flexible. Different wall thicknesses are possible if gas channels are designed into the part at the transition points. This permits uniform materialflows in the mold and avoids the high stresses and warpage that normally result from this sort of geometry.(7) Cycle time ReductionCompared with structural foam, gas-injection parts do not have the same inherent insulating characteristics, so that cycle times are faster-reportedly even faster than would be conventional injection of the same part with no hollow sections.(8) Resin savingGas assist plays a direct role in part-weight saving in the conversion of current tools. The main factor in reducing weight is that the part cavity is never completely filled. Another major contributor to resin saving is scrap reduction. With proper tool design, gas assisted allows scrap-free startups and production runs.B. Disadvantages of the GAIM processAll processes have their disadvantages, but those of GAIM and GAIMIC (Gas-assisted injection molding with internal-water cooling) appear relatively minor compared with their significant advantages.(1) Large hollow sectionsGIAM is not well suited for thin-walled hollow parts such as bottles or tanks. However, the thin-wall part has also tried out for some specific applications.(2) Vent holeThe gas must be vented prior to opening the mold, leaving a hole somewhere on the part. Normally this can be placed in a non-visible location, but if appearance or function is affected or secondary operations are required, it may be necessary to seal the hole.(3) Mold temperature controlSince wall thickness along the gas flow channel is a function of cooling rate, consistent wall thickness requires precise mold temperature control.(4) Surface blushThe gas channel may leave surface blush, which arises from differences in surface gloss leaves. The tendency for blush is a function of processing conditionsand types of plastics.(5) Unique designThe unique part design and mold design required in most cases to fully utilize that GAIM might be considered by some to be a disadvantage. The gas part design takes a relatively longer time than with the conventional injection molding process.(6)Extra cost of controllerIn order to control the gas injection, the process requires extra equipment. Gas-assisted injection molding with internal cooling requires a system for controlling the gas and the water, an expense not required with traditional injection molding.C. Types of process defects in the GAIMFingering, gas bubbles, hesitation lines, burning of resin, witness line cold slug, and gas blowout are typical defects normally encountered in GAIM.Fingering, or gas permeation, is a common problem encountered in GAIM. In fingering, gas escapes from the gas channel and migrates into undesired areas of the part. Severe gas fingering can result in significant reduction n in part stiffness, impact strength and reliabitity of the final molded part. During the gas holding phase, the transitional region between the gas channel and the flat area is possible for fingers to form within the flat area. In this case, the main cause of the fingering effect is the higher its shrinkage potential, and hence the greater danger of the fingering effect. In order to largely exclude the fingering effect through design, it is necessary to implement the following criteria: a basic wall thickness of 4mm or greater should be avoided for flat areas, a material with favorable solidification behavior should be selected, and the lowest possible gas pressure should be applied.Gas bubbles are caused by fingering. When fingering occurs, gas sometimes gets trapped in the thin-wall sections of the part where the gas is unable to fully vent. These trapped gases can cause bubbles that will still be in the gas core after the mold is opened.Hesitation lines appear on the surface of a part produced by GAIM when theshort shot of resin stops in the cavity, then starts moving again as the gas completes the fill.Burning of the resin can appear on either the outer surface of the part or within the gas channel itself. Burning of the part surface can be caused by gas pressure that is too high or by insufficient venting of the mold. Burning, the resin within the hollow sections of the part is also possible. Burning within the gas channel can cause gas injection pins to become plugged.On thin-walled parts molded in certain resins, a witness line, or gloss-level change, can occur over the gas channel. Excessive gas pressure can also cause witness lines over gas channels.When gas is injected through the molding machine nozzle, cold slugs of resin may occur on the part surface. A cold slug is caused when a small amount of unmelted resin is injected into the part.Gas blowout occurs when there is not enough resin in the cavity to hold the gas inside the part. If the part is short, gas will migrate to the non-filled area of the cavity and blow through. When blowout occurs, the part will sometimes look like a short shot.Most cases of defects are produced by the interface of the gas and the melt. These problems can be overcome by internal water-cooling between the interface of the gas and the melt.中文译文：气辅注射成型注射成型是一种很普通的生产方法，用于加工那种生产时难以控制和有复杂表面的商业塑件。
塑料注射成型外文文献翻译、中英文翻译、外文翻译
塑料注射成型外文文献翻译、中英文翻译、外文翻译外文翻译原文：Injection MoldingMany different processes are used to transform plastic granules, powders, and liquids into product. The plastic material is in moldable form, and is adaptable to various forming methods. In most cases thermosetting materials require other methods of forming. This is recognized by the fact that thermoplastics are usually heated to a soft state and then reshaped before cooling. Theromosets, on the other hand have not yet been polymerized before processing, and the chemical reaction takes place during the process, usually through heat, a catalyst, or pressure. It is important to remember this concept while studying the plastics manufacturing processes and polymers used.Injection molding is by far the most widely used process of forming thermoplastic materials. It is also one of the oldest. Currently injection molding accounts for 30% of all plastics resin consumption. Since raw material can be converted by a single procedure, injection molding is suitable for mass production of plastics articles and automated one-step production of complex geometries. In most cases, finishing is not necessary. Typical products include toys, automotive parts, household articles, and consumer electronics goods.Since injection molding has a number of interdependent variables, it is a process of considerable complexity. The success of the injection molding operation is dependent not only in the proper setup of the machine hydraulics, barrel temperaturevariations, and changes in material viscosity. Increasing shot-to-shot repeatability of machine variables helps produce parts with tighter tolerance, lowers the level of rejects, and increases product quality (i.e., appearance and serviceability).The principal objective of any molding operation is the manufacture of products: to a specific quality level, in the shortest time, and using repeatable and fully automaticcycle. Molders strive to reduce or eliminate rejected parts in molding production. For injection molding of high precision optical parts, or parts with a high added value such as appliance cases, the payoff of reduced rejects is high.A typical injection molding cycle or sequence consists of five phases;1. Injection or mold filling2. Packing or compression3. Holding4. Cooling5. Part ejectionPlastic granules are fed into the hopper and through an in the injection cylinder where they are carried forward by the rotating screw. The rotation of the screw forces the granules under high pressure against the heated walls of the cylinder causing them to melt. As the pressure building up, the rotating screw is forced backward until enough plastic has accumulated to make the shot. The injection ram (or screw) forces molten plastic from the barrel, through the nozzle, sprue and runner system, and finally into the mold cavities. During injection, the mold cavity is filled volumetrically. When the plastic contacts the cold mold surfaces, it solidifies (freezes) rapidly to produce theskin layer. Since the core remains in the molten state, plastic follows through the core to complete mold filling. Typically, the cavity is filled to 95%~98% during injection. Then the molding process is switched over to the packing phase.Even as the cavity is filled, the molten plastic begins to cool. Since the cooling plastic contracts or shrinks, it gives rise to defects such as sink marks, voids, and dimensional instabilities. To compensate for shrinkage, addition plastic is forced into the cavity. Once the cavity is packed, pressure applied to the melt prevents molten plastic inside the cavity from back flowing out through the gate. The pressure must be applied until the gate solidifies. The process can be divided into two steps (packing and holding) or may be encompassed in one step(holding or second stage). During packing, melt forced into the cavity by the packing pressure compensates for shrinkage. With holding, the pressure merely prevents back flow of the polymer malt.After the holding stage is completed, the cooling phase starts. During, the part is held in the mold for specified period. The duration of the cooling phase depends primarily on the material properties and the part thickness. Typically, the part temperature must cool below the material’s ejection temperature. While cooling the part, the machine plasticates melt for the next cycle.The polymer is subjected to shearing action as well as the condition of the energy from the heater bands. Once the short is made, plastication ceases. This should occur immediately before the end of the cooling phase. Then the mold opens and the part is ejected.When polymers are fabricated into useful articles they are referred to as plastics, rubbers, and fibers. Some polymers, forexample, cotton and wool, occur naturally, but the great majority of commercial products are synthetic in origin. A list of the names of the better known materials would include Bakelite, Dacron, Nylon, Celanese, Orlon, and Styron.Previous to 1930 the use of synthetic polymers was not widespread. However, they should not be classified as new materials for many of them were known in the latter half of the nineteenth century. The failure to develop them during this period was due, in part, to a lack of understanding of their properties, in particular, the problem of the structure of polymers was the subject of much fruitless controversy.Two events of the twentieth century catapulted polymers into a position of worldwide importance. The first of these was the successful commercial production of the plastic now known as Bakelite. Its industrial usefulness was demonstrated in1912 and in the next succeeding years. T oday Bakelite is high on the list of important synthetic products. Before 1912 materials made from cellulose were available, but their manufacture never provided the incentive for new work in the polymer field such as occurred after the advent of Bakelite. The second event was concerned with fundamental studies of the nature polymers by Staudinger in Europe and by Carohers, who worked with the Du Pont company in Delaware. A greater part of the studies were made during the 1920’s. Staudinger’s work was primarily fundamental. Carother’s achievements led t o the development of our present huge plastics industry by causing an awakening of interest in polymer chemistry, an interest which is still strongly apparent today.The Nature of ThermodynamicsThermodynamics is one of the most important areas ofengineering science used to explain how most things work, why some things do not the way that they were intended, and why others things just cannot possibly work at all. It is a key part of the science engineers use to design automotive engines, heat pumps, rocket motors, power stations, gas turbines, air conditioners, super-conducting transmission lines, solar heating systems, etc.Thermodynamics centers about the notions of energy, the idea that energy is conserved is the first low of thermodynamics. It is starting point for the science of thermodynamics is entropy; entropy provides a means for determining if a process is possible.This idea is the basis for the second low of thermodynamics. It also provides the basis for an engineering analysis in which one calculates the maximum amount of useful that can be obtained from a given energy source, or the minimum amount of power input required to do a certain task.A clear understanding of the ideas of entropy is essential for one who needs to use thermodynamics in engineering analysis. Scientists are interested in using thermodynamics to predict and relate the properties of matter; engineers are interested in using this data, together with the basic ideas of energy conservation and entropy production, to analyze the behavior of complex technological systems.There is an example of the sort of system of interest to engineers, a large central power stations. In this particular plant the energy source is petroleum in one of several forms, or sometimes natural gas, and the plant is to convert as much of this energy as possible to electric energy and to send this energy down the transmission line.Simply expressed, the plant does this by boiling water andusing the steam to turn a turbine which turns an electric generator.The simplest such power plants are able to convert only about 25 percent of the fuel energy to electric energy. But this particular plant converts approximately 40 percent;it has been ingeniously designed through careful application of the basic principles of thermodynamics to the hundreds of components in the system.The design engineers who made these calculations used data on the properties of steam developed by physical chemists who in turn used experimental measurements in concert with thermodynamics theory to develop the property data.Plants presently being studied could convert as much as 55 percent of the fuel energy to electric energy, if they indeed perform as predicted by thermodynamics analysis.The rule that the spontaneous flow of heat is always from hotter to cooler objects is a new physical idea. There is noting in the energy conservation principle or in any other law of nature that specifies for us the direction of heat flow. If energy were to flow spontaneously from a block of ice to a surrounding volume of water, this could occur in complete accord with energy conservation. But such a process never happens. This idea is the substance of the second law of thermodynamics.Clear, a refrigerator, which is a physical system used in kitchen refrigerators, freezers, and air-conditioning units must obey not only the first law (energy conservation) but the second law as well.To see why the second law is not violated by a refrigerator, we must be careful in our statement of law. The second law of thermodynamics says, in effect, that heat never flowsspontaneously from a cooler to a hotter object.Or, alternatively, heat can flow from a cooler to a hotter object only as a result of work done by an external agency. We now see the distinction between an everyday spontaneous process, such as the flow of heat from the inside to the outside of a refrigerator.In the water-ice system, the exchange of energy takes place spontaneously and the flow of heat always proceeds from the water to the ice. The water gives up energy and becomes cooler while the ice receives energy and melts.In a refrigerator, on the other hand, the exchange of energy is not spontaneous. Work provided by an external agency is necessary to reverse the natural flow of heat and cool the interior at the expense of further heating the warmer surroundings.译文：塑料注射成型许多不同的加工过程习惯于把塑料颗粒、粉末和液体转化成最终产品。
dmg硅橡胶印模材料
dmg硅橡胶印模材料
DMG硅橡胶印模材料。
DMG硅橡胶印模材料是一种高性能的印模材料，广泛应用于模具制作、手工艺品制作、工艺品制作、玩具制作等领域。
它具有优异的柔韧性、耐磨性、耐高温性和化学稳定性，因此备受制模行业的青睐。
首先，DMG硅橡胶印模材料具有优异的柔韧性，能够轻松实现复杂模具的制作。
其柔软度和弹性可以有效地复制模具细节，使制作的产品更加精致和逼真。
同时，它的柔韧性也使得模具的脱模更加容易，不易损坏模具和产品。
其次，DMG硅橡胶印模材料具有出色的耐磨性，能够长时间保持模具的细节和表面光滑度。
在模具制作过程中，频繁的使用和脱模往往会导致模具表面磨损和细节丢失，而DMG硅橡胶印模材料可以有效地延长模具的使用寿命，减少制作成本。
此外，DMG硅橡胶印模材料还具有出色的耐高温性能，能够在高温环境下稳定工作。
在一些需要加热处理的模具制作过程中，DMG硅橡胶印模材料能够保持稳定的性能，不会因高温而失去弹性或变形，确保模具制作的质量和效率。
最后，DMG硅橡胶印模材料具有优秀的化学稳定性，能够在常见的化学溶剂和材料中保持稳定。
这使得它可以广泛应用于不同的制模领域，无论是制作树脂模具、石膏模具还是混凝土模具，都能够表现出色。
总的来说，DMG硅橡胶印模材料以其优异的柔韧性、耐磨性、耐高温性和化学稳定性，成为模具制作领域的首选材料之一。
它的出色性能不仅能够满足模具制作的需求，还能够为手工艺品制作、工艺品制作、玩具制作等领域提供高质量的模具支持。
相信随着技术的不断进步和应用领域的不断拓展，DMG硅橡胶印模材料将会有更广阔的发展空间，为各行各业的制作工作带来更多便利和可能。
dmg硅橡胶印模材料
dmg硅橡胶印模材料
DMG硅橡胶印模材料。
DMG硅橡胶印模材料是一种用于制作模具的特殊材料，它具有优异的柔韧性
和耐磨性，适用于各种印模制作工艺。
本文将介绍DMG硅橡胶印模材料的特性、
应用范围以及制作方法，希望能为您对该材料有一个全面的了解。
DMG硅橡胶印模材料具有良好的流动性和成型性，能够快速填充模具，并在
一定时间内固化成形。
其硬度范围广泛，从软硬度到硬硬度均可满足不同工艺要求。
同时，DMG硅橡胶印模材料还具有出色的抗拉强度和耐磨性，能够长期保持模具
的稳定性和耐用性。
在实际应用中，DMG硅橡胶印模材料被广泛用于模具制作领域。
例如，它可
以用于制作工艺品模具、玩具模具、模型模具等。
由于其优良的柔韧性和精细的表面质感，DMG硅橡胶印模材料还被应用于艺术品雕刻模具的制作。
此外，由于其
耐高温性能，它还可以用于制作热压模具、注塑模具等高温工艺的模具。
制作DMG硅橡胶印模的方法相对简单，首先需要将硅橡胶材料与固化剂按一
定比例混合均匀，然后倒入模具中进行固化。
在固化过程中，可以根据需要进行真空脱泡以去除气泡，以保证模具的成型质量。
固化时间一般较短，可以根据材料的硬度和厚度进行调整。
固化完成后，即可取出模具进行后续加工和使用。
总的来说，DMG硅橡胶印模材料具有优良的性能和广泛的应用范围，是模具
制作领域中的重要材料之一。
它不仅可以满足各种工艺要求，还能够为模具制作提供高效、稳定的解决方案。
希望本文能够帮助您更深入地了解DMG硅橡胶印模材料，并在实际应用中发挥其优势。
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P Dunne and G Byrne *Department of Mechanical Engineering,School of Engineering,University College Dublin,Republic of IrelandAbstract:The inherent technical limitations of rapid prototyping systems have led to the developmentof rapid tooling techniques.These techniques are capable of producing prototypes in ®nal materials bythe intended manufacturing process.One rapid tooling process that provides a low cost and rapidroute to the manufacture of injection-moulded thermoplastic components is enhanced siliconemoulding.During the moulding cycle the mould deforms under the pressures and temperaturesexperienced and components produced su er a loss of dimensional accuracy.An analytical and experimental investigation was undertaken to quantify the dimensional accuracyof components produced by the process,and to identify the moulding parameters which contribute tothe loss of dimensional accuracy.A mould was produced from a stereolithography master pattern andused to injection-mould components in high-impact polystyrene under various moulding conditions.Moulded components produced were typically oversized with a loss of dimensional accuracy of theorder of 0.3±0.6mm.Two parameters,namely injection pressure and mould temperature,werefound to have an in¯uence on dimensional accuracy.The injection pressure causes the mould cavity to expand and results in manufacture of componentswhich are ponents produced at an injection pressure of 16MPa were on average0.34mm (1.3per cent)oversized in width and 0.36mm (11.3per cent)oversized in depth.Thoseproduced at an injection pressure of 20MPa were oversized by an average of 0.45mm (1.8per cent)in width and 0.59mm (18.6per cent)in depth.An increase in mould temperature caused areduction in the size of the mould cavity.This was because the rubber mould was restricted in ametal mould frame.The rubber mould expands into the free space of the ponentsproduced at mould temperatures of 50,70and 908C were oversized in width by an average of0.37mm (1.5per cent),0.34mm (1.3per cent)and 0.20mm (0.8per cent)respectively.Keywords:vacuum casting,rapid tooling,silicone mouldingNOTATIONddepth of component (mm)Dwidth of component (mm)wdistance from gate (mm)1INTRODUCTION Materials and processing advances within the injection-moulding industry are allowing increasingly complex components to be designed and manufactured [1].Associated with such components are equally complex moulds which require precision manufacture from tool steels.Consequently,the design and manufacture of a production injection mould are both time consuming and expensive.It is,therefore,vital that the component design be evaluated thoroughly with regard to perfor-mance and manufacturability before committing toexpensive production tooling [2].Such evaluation isgenerally achieved through manufacture of a prototypeof the component.Within the ®eld of injection-mouldingproduct design,the term prototype generally refers toa physical model which embodies some or all elementsof a product.Prototypes may be divided into fourclasses:(a)proof of concept prototypes which are usuallysimple representations of a design concept,51B10003#IMechE 2004Proc.Instn Mech.Engrs Vol.218Part B:J.Engineering Manufacture The MS was received on 6June 2003and was accepted after revision for publication on 9October 2003.*Corresponding author:Department of Mechanical Engineering,School of Engineering,University College Dublin,Dublin 4,Republic of Ireland.(b)scale prototypes which are typically non-functionalmodels used to communicate speci®c design con-cepts,(c)experimental prototypes which are functionalmodels embodying the main working elements of the design and(d)full working prototypes which are completely func-tional models of the design and should be both technically and aesthetically complete[3].There are three main routes to the manufacture of a prototype for the injection-moulding design process: machining,rapid prototyping and rapid tooling.The application of machining and rapid prototyping tech-niques to prototype manufacture is established.However, the prototypes produced do not have the same materials and process characteristics as moulded components. Rapid tooling techniques overcome these limitations and involve the manufacture of prototypes from low-cost moulds[4].The most widely used rapid tooling technique is vacuum casting as it is capable of providing low-cost replicas in relatively short time periods with minimal expense.This process involves the manufacture of a silicone rubber mould from a master pattern.This mould is then used in the manufacture of prototypes by vacuum casting polyurethane materials[5].The advantages of using rubber mould materials include ease of processing for mould manufacture,replication of detail and textures,and elasticity which allows moulded components to be removed from the mould without causing any damage to the mould or the moulded component.This latter point is a particular problem for many low-cost rapid tooling techniques. Silicone rubber moulds are generally only capable of producing low volumes of prototypes.The mould life for prototypes with intricate features is between20and 30.After this,areas of the mould start to tear and proto-types are produced with deformed or missing features. The mould life for prototypes without intricate features can be as high as60.Although widely employed,vacuum casting does not provide a complete solution to the materials and process limitations of machining and rapid prototyping tech-niques.The low sti ness of the silicone rubber restricts the range of materials that can be processed to those which can be gravity cast;typically polyurethanes are used.The pressures required to inject engineering thermo-plastics cause excessive deformation of the silicone mould. Consequently,the process is only capable of producing prototypes in replica materials by a low-pressure casting, rather than an injection(high-pressure)-moulding process. To overcome these limitations,an enhanced silicone moulding process may be used.This process involves impregnation of the silicone rubber with metal particulate ®ller to improve the sti ness of the rubber material and to allow injection moulding of thermoplastics.2ENHANCED SILICONE MOULDING PROCESS 2.1MaterialThe material used is a moulding-grade silicon rubber impregnated with iron powder particulate®ller.Theaverage particle size of the iron powder is2.6m m witha standard deviation of1.1m m.The silicone rubber andiron powder are mixed in a1:1ratio by weight.Thechoice and proportion of®ller material used is based on the work of Venus et al.[6]who investigated thee ects of®ller ratios on the processability and®nalmechanical properties of®lled silicone rubbers.The useof a1:1ratio was found to provide a good balancebetween pourability of the mixture during processingand as-cured material sti ness.This particulate-reinforced silicone rubber material is referred to asenhanced silicone rubber.Comparative tests were undertaken to quantify thee ect of®ller addition on the mechanical properties ofthe pression tests showed an average increase in stress required to strain the material up to¢0.6strain of approximately49per cent.The compres-sion tests were carried out in accordance with BS903:Part A4,on cylindrical samples(of diameter29mmand length12.5mm)using a constant displacement rate of10mm/min with four preliminary loading cycles to account for the stress-softening e ect(Mullins e ect). Hardness tests carried out in accordance with BS903: Part A26showed an increase in hardness of approxi-mately24per cent from42.9Shore A for the un®lled material to53.4Shore A for the®lled material[6].2.2ProcessingThe mould material is processed in®ve stages;mixing of the mould material constituents,primary degassing,cast-ing,secondary degassing and material curing.The material is prepared by addition and mixing of catalyst(10wt%)to the silicone rubber followed by addition and mixing of the iron powder particles.Tests were undertaken to ensure complete wetting of the particles and to assess the distribution of particles through the material.Samples were moulded from0.1l of material prepared at mixing times of2,4,6,8and 9min.Each sample was inspected at six locations on the upper surface and six locations on the lower surface using optical microscopy.Inspection images were con-verted to a binary image and the percentage powder by area calculated using image analysis software.Figure1 plots the average percentage powder by area against mixing time.It can be seen that the mixture becomes more homogeneous with increasing mixing time as the scatter reduces.The di erence between results for the upper and lower surface indicate that di erential settle-ment due to gravity is not signi®cant[8].52P DUNNE AND G BYRNEProc.Instn Mech.Engrs Vol.218Part B:J.Engineering Manufacture B10003#IMechE2004During mixing of the constituents,air becomes entrapped in the mixture and must be removed before the material cures.This is achieved by primary degassing of the material under vacuum.Tests were undertaken to determine the minimum primary vacuum degassing time. Samples were produced under various vacuum times, ranging from0to20min at740mmHg.The samples were sectioned and the quantity and location of air inclusions obtained using image analysis.It was shown that no visible air inclusions exist in samples after 20min primary vacuum degassing time.Once the entrapped air has been removed,the material is cast to®nal form.Casting is undertaken at room tem-perature and atmospheric pressure.A second degassing period is undertaken after the material has been cast. This is to ensure removal of any further air inclusions that may have resulted during the casting stage.Finally the material is allowed to cure for24h at room temperature.This is based on the manufacturer’s recom-mendations[9].3EXPERIMENTAL PROCEDURE3.1Mould design and manufactureA simple rectangular component geometry measuring 80mm£25.4mm£3.175mm was chosen.The compo-nent was®lled via a parabolic runner with an elbow,of diameter3.5mm and length25mm,feeding an eccentric circular end gate.The component geometry and runner con®guration are shown in Fig.2a.The mould consisted of a metal mould frame with an enhanced silicone rubber insert as shown in Fig.2b. The mould was manufactured by casting the silicone rubber±metal powder mix against the master pattern to form the mould.A stereolithography model with a layer thickness of0.15mm made in Ciba Geigy SL5170 epoxy resin was used as the master pattern.The mould consisted of a simple two-plate mould con®guration with a planar parting line.The parting line was chosen such that the cavity was contained in one mould half only,allowing a¯at metal plate to be used for the other half.Two type K thermocouples were inserted into the curing rubber at two locations along the length of the cavity,approximately15mm from the cavity ends and between2and8mm below the cavity surface.These were used to monitor the mould temperature.It was not necessary to incorporate an ejector system as the material can be¯exed to remove the moulding or a cool-ing system as the mould is only intended for low-volume manufacture and therefore cycle time is not critical.Three venting channels were cut into the rubber mould at the end of the cavity after the rubber had cured.3.2Injection mouldingInjection moulding of high-impact polystyrene was carried out using a semiautomatic vertical plunger-type moulding machine with horizontal clamping.The plunger was actuated by an air cylinder.The barrel was heated using band heaters and the mould was heated using cartridge heaters.A total of45components were moulded as outlined in Table 1.The initialsettings Fig.1Percentage powder by area against mixing timeFig.2(a)Component geometry used for the dimensional accuracy investigations and(b)moulddesignTable1Experimental planDIMENSIONAL ACCURACY OF INJECTION-MOULDED COMPONENTS53 B10003#IMechE2004Proc.Instn Mech.Engrs Vol.218Part B:J.Engineering Manufactureused to mould components are given in Table 2. These initial settings were obtained from manufacturers data,literature and moulding trials carried out on a machined metal mould with similar component geometry[8,10,11].The experimental plan is based on varying the four moulding parameters.The parameters,namely hold time,injection temperature,injection pressure and mould temperature,were chosen as they are known to have an e ect on dimensional accuracy[10].Owing to the limited life of enhanced silicone rubber moulds it was not feasible to undertake a full factorial experiment for the four parameters.3.3Measurement proceduresThe width and depth of moulded components were measured at various points along the length using a micrometer.The width was measured at mid-depth and at nine locations along the length in10mm intervals. The depth was measured at mid-width and at nine locations along the length in10mm intervals.4RESULTS AND DISCUSSIONThe error bars represent the maximum and minimum values obtained in all cases.4.1Hold timesThe form of the hold time graphs(Fig.3)shows that the components produced are typically oversized.For the case of the width curves,it can be seen that the width increases towards the central region of the cavity (30mm<D<50mm).This may be attributed to: (a)the fact that the central region is subject to the mostdeformation as a result of mould heating and (b)the fact that the central region of the cavity is lesswell supported by the surrounding material and so deforms more under loading.The general trend of the depth curves is similar to that of the width curves with the exception of the region close to the injection point(0mm<D<20mm).In this region,the e ects of proximity to the gate are evident. The components produced using a2s hold time are short shots.This is most clearly seen from the depth measurement results where the depth falls below the nominal,towards the end of the cavity(D>55mm). The components produced at5s hold time were found to be acceptable.The hold time necessary to pack the mould adequately therefore lies between2and5s.The 5and10s hold time results are similar.The average di erence between the widths of the5and10s com-ponents is0.03mm with a maximum di erence of 0.06mm.The results for the depths are similar,with an average di erence of0.03mm and a maximum di erence of0.05mm.This level of similarity,which is well within the scatter,indicates that lengthening of the hold time beyond5s has no e ect on dimensional accuracy.4.2Injection temperatureThe results for the components produced at various injection temperatures(Fig.4)are similar to the hold time results.The variation in injection temperature has no e ect on the dimensional accuracy of the components produced.The average di erence between the widthsof Table2Initial moulding parameter settingsFig.3Average width and depth measurements for moulded components produced at three di erent hold times54P DUNNE AND G BYRNEProc.Instn Mech.Engrs Vol.218Part B:J.Engineering Manufacture B10003#IMechE2004components produced at 200,215and 2308C injectiontemperatures are of the order of 0.04mm with a maxi-mum of 0.08mm.The results for the depths are similarwith an average di erence of 0.03mm and maximumdi erence of 0.06mm.4.3Injection pressureThe results for the components produced at variousinjection pressures are presented in Fig.5.The mostsigni®cant point to note is the di erence between thecurves.This highlights the in¯uence of injection pressureon the dimensional accuracy of the moulded component.The dimensions of the components produced at12.5MPa fall below nominal in the region between 50and 60mm from the gate.This equates to a situationwhere the injection pressure is insu cient to ®ll andpack the mould cavity completely.As a result,shortshots which have a similar appearance to those producedusing 2s hold times are produced.The use of 16MPainjection pressure was found to overcome this problemwith successful ®lling and packing of the mould cavitypossible.The components produced at 16MPa wereoversized in width by an average of 0.34mm (1.3percent)and in depth by an average of 0.36mm (11.2percent).The results for 20MPa injection pressure show a further deviation from the desired nominal dimensions,these components were oversized in width by an average of 0.45mm (1.8per cent)and in depth by an average of 0.59mm (18.4per cent).4.4Mould temperature The results for the components produced at various mould temperatures are presented in Fig.6.The main point to note is the di erence in the width of the compo-nents produced at the three mould temperatures.The average widths of the components are 25.77,25.74and 25.60mm for mould temperatures of 50,70and 908C respectively.These average widths correspond to compo-nents which are oversized by 0.37mm (1.5per cent),0.34mm (1.3per cent)and 0.20mm (0.8per cent)for the three mould temperatures respectively.The general trend is that the width of the components reduces with increasing mould temperature.This is due to thermal expansion of the rubber mould which results in a reduc-tion in cavity size.The form of the width curves is di erent from those previously observed.At the lower mould temperature of 508C the width is greater in the region close to the injection point.This is concurrent with insu cient mould heating.The material entering the mould cools too rapidly and impedes ®lling oftheFig.4Average width and depth measurements for moulded components produced at three injectiontemperaturesFig.5Average width and depth measurementsfor moulded components produced at three injection pressuresDIMENSIONAL ACCURACY OF INJECTION-MOULDED COMPONENTS 55B10003#IMechE 2004Proc.Instn Mech.Engrs Vol.218Part B:J.Engineering Manufacturemould cavity.This leads to an increase in the pressurewithin the injected material and results in greater defor-mation of the mould cavity as observed.4.5Summary of moulded component resultsThe overall results are summarized in Fig.7which plotsthe average width and depth results for the main mould-ing tests.The results clearly illustrate the e ects of vary-ing the moulding parameters and show that dimensionalaccuracy is dependent on injection pressure and mouldtemperature and is not dependent on injection tempera-ture and hold time.5CONCLUSIONSRectangular sample components measuring 80mm £25.4mm £3.175mm were moulded under various con-ditions in high-impact polystyrene using a plunger-typemoulding machine.The components were measured and found to be generally oversized with a loss of dimen-sional accuracy of the order of 0.3±0.6mm.Of the four parameters varied (hold time,injection temperature,mould temperature and injection pressure),two were found to have an e ect on dimensional accuracy.These were injection pressure and mould temperature.For the case when injection pressure was varied,it was found that an increase in injection pressure leads to an increase in component size and hence greater loss of dimensional accuracy.For the case of mould tempera-ture it was found that increasing the mould temperature leads to an improvement in dimensional accuracy.The mould temperature causes the enhanced silicone rubber insert to expand in the mould frame.This results in a reduction in cavity size and moulding of a more accurate component;i.e.thermal expansion of the mould counter-acts some of the deformation of the mould under the pressure of the injected material.This investigation has focused on identifying the moulding parameters that contribute to the lossof Fig.6Average width and depth measurements for moulded components produced at three mouldtemperaturesFig.7Summary of main moulding test results.Results indicated by a white bar indicate that mouldings wereshort shots56P DUNNE AND G BYRNEProc.Instn Mech.Engrs Vol.218Part B:J.Engineering Manufacture B10003#IMechE 2004dimensional accuracy in the enhanced silicone moulding process.With knowledge of the dominant moulding parameters it is envisaged that a®nite element model could be developed to predict,and ultimately to compen-sate for,the dimensional accuracy losses in the process. The primary advantage of developing a®nite element model would be the ability to predict dimensional accu-racy losses in more complicated component geometries. ACKNOWLEDGEMENTSThe authors wish to acknowledge the support of the Advanced Manufacturing Technologies Ireland Pro-gramme for Advanced Technology and the Science and Innovation Directorate at Enterprise Ireland. 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