材料成型及控制工程中英文对照外文翻译文献
材料成型及控制工程专业毕业设计(论文)外文翻译
中文2500字本科毕业设计翻译学生姓名：*****班级：*****班学号：*****学院：材料科学与工程学院专业：材料成型及控制工程指导教师：***** 副教授2011年3月25日Section 4 – Die Design and Construction Guidelines for HSS Dies General Guidelines for Die Design and ConstructionDraw DiesHigher than normal binder pressure and press tonnage is necessary with H.S.S. in order to maintain process control and to minimize buckles on the binder. Dies must be designed for proper press type and size. In some cases, a double action press or hydraulic press cushion may be required toachieve the necessary binder forces and control. Air cushions or nitrogen cylinders may not provide the required force for setting of draw beads or maintaining binder closure if H.S.S. is of higher strength or thickness.Draw beads for H.S.S. should not extend around corners of the draw die. This will result in locking out the metal flow and cause splitting in corners of stamping. D raw beads should “run out” at the tangent of the corner radius to minimize metal compression in corners, as shown in figure 16 on page 47. Better grades of die material may be necessary depending on the characteristics of the HSS, the severity of the part geometry, and the production volume. A draw die surface treatment, such as chrome plating, may be recommended for outer panel applications.Form and Flange DiesPart setup in form and flange dies must allow for proper overbend on all flanges for springback compensation. Springback allowance must be increased as material strength increases; 3 degrees for mild steels, but 6 degrees or morefor HSS.Punch radii must be fairly sharp. 1t for lower strength steels. Higher strength steels may require larger radii, but keeping them as small as practical will reduce springback in the sidewalls.Flange steel die clearance must be held to no more than one metal thickness clearance to reduce springback and sidewall curl.Form and flange steels should be keyed or pocketed in the casting to avoid flexing.Flange steels should be designed to wrap over and coin the flange break in order to set the break and reduce springback. See figure 17 on page 48.Die strength must not be compromised with light-weight die construction. High strength steel will require a stiffer die to resist flexing and the resultant part distortions, especially for channel or “hat-section” parts. This type of part can also cause serious die damage if double blanks occur.Cutting DiesTo reduce press tonnage requirements and extend die life, a minimum shear of four to six times metal thickness in twelve inches of trim steel length is recommended.To reduce die maintenance, maximum trim angles should be about 5° to 10°less than those used for mild steel. Trim steels should be keyed or pocketed in casting to avoid flexing. Die clearance should be 7 to 10% of metal thickness.Drawbead TypesConventional Drawbeads Run-out Drawbeads For H.S.S.Lock Beads for Stretch-Form DieFigure 161. Providing a vertical step in the flange stiffens and straightens the flange, stopping sidewall curl as well as springback.2. The addition of stiffening darts helps maintain a 90-degree flange.3. By adding a horizontal step along the flange, the flange is stiffened, resulting in reduced springback.4. Back relief on the upper flange steel allows for extra pressure to be applied futher out on the formed radius.Section 5 – Die Tryout Guidelines for High Strength Steel DiesGeneral Guidelines for Die TryoutDraw DiesHigher draw die binder pressure and press tonnage will be necessary in order to maintain process control and draw parts without buckles. A double action press or a press with hydraulic cushion may be required in some cases to achieve the required binder forces.HSS draw die operations will require sheet steel lubricants that are formulated for extreme pressures. Mill oils will not provide sufficient lubricity for most applications. Pre-lubes or dry film lubricants may be necessary for process control.Die plan view punchline corner radii should be larger than with mild steels to avoid buckling in the corners of the binder.Stretch Form DiesLock beads may require modification to avoid cracking or tearing with higher strength grades of HSS. Opening side walls of beads and enlarging corner radii will avoid cracking of high strength sheet steel. Lock beads should be continuous around the punchline for stretch form dies.For large panels from stretch-form dies, such as a roof panel or hood outer, elastic recovery may result in a shrunken panel that does not fit well on the male die member of the trim or flange dies. This problem is corrected by adding a “plus” factor to the overall part dimensions of the draw die or stretc hform die punch. This “plus” is usually no more than 2.5 mm at the center of the sides and the front, tapering to 0.0mm at the corners of the part profile on the punch. Finish part profile is defined, and plus is removed, in the main flange die.Form and Flange DiesThe punch radius should be fairly sharp with 1 or 2t used for lower strength steel. HSS may require larger radii, but as small as practical to reduce springback of sidewalls.The flange steel radius affects sidewall curl and springback on any offset flanges. This radius should also be small to reduce springback of side flanges. Overbend for springback compensation must be increased as tensile strength increases: 3 degrees is standard for mild steels, but 6 degrees or more will be required for HSS.Flange steel die clearance should be tight, maintaining no more than one metal thickness clearance to reduce springback and sidewall curl.Cutting DiesTo reduce press tonnage requirements and extend die life, a minimum shear of four to six times metal thickness in twelve inches of trim steel length is required.Die clearance should be 7 to 10% of metal thickness for HSS.To reduce trim steel maintenance, reduce maximum trim angles by about 5° to 10° from those used for mild steel. Trim steels should be keyed or pocketed in the casting to avoid flexing.Die Tryout When Using Bake Hardenable SteelIn order to obtain the maximum benefits of BHS, tryout of the dies should be performed as follows: Circle grid analysis must be performed on a panel before any die rework is attempted. With the gridded panel as a reference, the die can be modified to provide a minimum biaxial stretch of 2.0%. Stretch-form or draw dies are best for this material.For rough or functional tryout, it is possible to use mild steel with a 6% to 8% gauge increase to perform the normal process of die preparation. This alleviates complications when the BHS strengthens between each die being tried out. The reason for this is the time lag that normally occurs between a panel being formed and its use in the next operation.When the entire line of dies is ready for approval, all dies must be set in line. Panels should be run through all the die operations consecutively. This will avoid some of the strengthening effects of time delays between stamping operations that can cause variation in panels. Dimensional approval of the panel will be most difficult if this procedure is not followed.The strengthening reaction in the BHS can cause dimensional variation in flanges since springback will vary with time as the strength increases. This is why running the panel through all die operations consecutively is crucial to a successful buyoff.Part BuyoffTo reduce the part buyoff time and eliminate many hours of tryout time, the benefits of functional build must be considered. This procedure has beenproven to save time and money by concentrating on an acceptable sub-assembly rather than making each stamping to part specifications. Those parts that are easiest to change are revised to suit the sub-assembly dimensional targets. Those parts that do not affect the sub-assembly quality are not changed, but the detail part specifications are revised. The functional build process will eliminate excessive tryout hours if used for part buyoff on HSS stampings.In addition to saving tryout time and die rework costs with functional build, lower part variation can also be realized. Two dimensional challenges faced by the die maker when first trying out dies are to reduce the dimensional variation from nominal specifications, and to reduce the short term variationfrom part to part. The typical priority is to first minimize part-to-part variation and later address nominal deviation. A strong argument for this strategy is that the deviation from nominal is not precisely known until a dimensionally consistent part can be evaluated. The results are a dimensionally consistent part even though a number of checkpoints may deviate from nominal, and perhaps even be out of tolerance. In many situations when dimensions on the die are reworked to shift them closer to nominal, they become less stable and result in higher part-to-part variation. The functional build philosophy evaluates the acceptability of the part after it becomes stable, and before minor dimensional shifts are made. Large deviant or critical dimensions may be identified for rework even with functional build. There are dimensions that can often be spared rework based on a functional build approach. In these cases, the part remains more stable and the die more robust because less rework occurs while attempting to shift dimensions.For more information on functional build, refer to the Auto/Steel Partnership publication. “Event-Based Functional Build: An Integrated Approach to Body Development”.第四节-高强度钢模具设计和制造指南对模具设计和制造的一般准则拉深模具为了控制高强度钢的成形并减少板料边缘的弯曲，高强度钢成型时的压力和吨位高于一般情况是必要的。
材料成型及控制工程专业英语
材料成型及控制工程专业英语Mechanical property机械性能austenitic奥氏体的martensite 马氏体Plastic deformation塑性变形stress concentrator应力集中点bar棒材beam线材sheet板材ductile可延展的stress relief应力松弛austenitie奥氏体 martensite马氏体normalize正火temper回火anneal正火harden淬火close-die forging模锻deformation rate变形速度diffusion扩散overheat过热Work hardening加工硬化dislocation density位错密度die模具residual strain残留应变as-forged锻造的injection mold注射模molding shop成型车间clamping force合模力grind磨削drop stamping锤上模锻nickel-base superalloy镍基合金insulation 隔热burr毛刺injection capacity注射容量deterioration变化、退化discrete不连续的abrasive磨损welding焊接metallurgical 冶金的Formation of austenite奥氏体转变The transformation of pearlite（珠光体）into austenite can only take place at the equilibrium critical point（临界温度）a very slow heating as follows from the Fe-C constitutional diagram（状态图）. under common conditions, the transformation is retarded and results in overheating,i.e.occurs at temperatures slightly higher than those indicated in the Fe-C diagram.The end of the transformation iS characterized by the formation of austenite and the dis—appearance of pearlite(ferrite+cementite)．This austenite is however inhomogeneous even in the volume of a single grain．In places earlier occupied by lamellae（层片）(or grains)of a pearlitic cementite，the content of carbon is greater than in places of ferritic lamellae．This is why the austenite just formed is inhomogeneous.In order to obtain homogeneous （均匀的）austenite，it is essential on heating not only to pass through the point of the end of pearlite to austenite transformation，but also to overheat the steel above that point and to allow a holding time to complete the diffusion（扩散） processes in aus-tenitie grains．为了获得均匀的奥氏体，在加热过程中通过珠光体的结束点向奥氏体转变是必要的，而且对过热刚以上的点，允许持续一定时间来完成奥氏体晶粒的扩撒过程。
材料成型与控制工程专业设计外文文献翻译固态微孔丙烯腈丁二烯苯乙烯泡沫塑料本科毕业论文
毕业设计外文文献译文及原文学生：学号：院（系）：机电工程学院专业：材料成型与控制工程指导教师：2011 年 6 月 8 日Solid-State Microcellular Acrylonitrile-Butadiene-Styrene FoamsSUMMARYMicrocellular ABS foams are a novel familv of materials with the potential to significantly reduce material costs in a number of applications that currently use solid polymer. ABS foams were produced using carbon dioxide in a solid-state process. Solubility and diffusivity of C02 in ABS was measured, and the latter was found to depend significantly on the gas concentration. The useful range of process-space for ABS-CO2 was characterized. Closed cell ABS foams were produced with densities ranging from 1.03 g/cm3 (almost completely solid) to 0.09g/cm3.It was determined that there are many different processing conditions that can produce microcellular ABS foams that have the same density. The cell nucleation density was of the order of 10 cells per cm3, and the average cell sizes observed ranged from 0.5 um to 5.6 um.INTRODUCTIONABS (Acrylonitrile-butadiene-styrene) has grown to become one of the most widely used thermoplastic in the world because of the wide range of available properties. ease of processing, and a good balance between price and performance. ABS is an amorphous copolymer alloy, with acrylonitrile bringing chemical resistance and heat stability, butadiene bringing toughness, and styrene providing good processing characteristics.These qualities provide an excellent engineering thermoplastic that is used for a wide range of products, including computer housings, automotive interiors, appliances, and building materials. In many applications, the solid ABS can be replaced by relatively high density microcellular foams, since the properties of solid ABS are not fully utilized. Currently, the only process than can produce foams suitable for thin cross-sections is the solid-state microcellular process originally developed at MIT as a way to produce high strength polymer foams which can reduce the amount of material used in manufactured products.This process produces foams with a very large number of very small cells, typically on the order of 10 um diameter, and thus the phase "microcellular foams" was coined.The batch microcellular process has two stages. In the first stage a thermoplastic sample is placed in a pressure vessel which is then pressurized with a non-reacting gas. Carbon dioxide and nitrogen are typically used as the foaming agents because of their low cost and high solubility in most polymers. The polymer sample absorbs the gas until an equilibrium gas concentration is reached. At this point. the sample is removed from the pressure vessel. In the second stage of the microcellular process the sample is heated, typically in a hot bath, to induce foaming. The temperature of the hot bath is in the neighbourhood of the glass transition temperature of the polymer, and thus the polymer remains in a solid, or rubbery state, well below the melting point, during the entire process. To distinguish these foams from the common foams made from polymer melts, they are described as "solid state" foams.The process described above is a batch process used to produce relatively small amounts of foam specimens at a time. The production capability of the solid-state microcellular foams has increased with the development of the semi-continuous process.In the semi-continuous process the sheet of polymer placed in the pressure vessel is replaced with a roll of polymer which has a gas permeable material rolled up in it to allow gas to diffuse into the entire surface of the roll. The polymer roll and gas permeable material are first separated, and then the polymer sheet is drawn through a hot bath to foam, and a cold bath if necessary to quench the structure.Microcellular foams can be produced with a wide range of densities and with an integral skid. Due to their potential as a novel family of materials, a number of polymer-gas systems have been explored in recent years, including polystyrene, polycarbonate, PET, PETC, and PVC.In this paper we present a detailed experimental characterization of the ABS-C02 system, and explore the effects of key process parameters on the microstructure.EXPERIMENTALCommercially available Cycolac GPX 3700 ABS, manufactured by General Electric was used in this study. All of the specimens were produced from 1.5 mm thick sheet with natural colour. The unprocessed material has a density of 1.04 g/cm3, and a glass transitions temperature of about 116℃.Solubility and diffusivity measurementsSpecimens were cut from 1.5 mm thick sheet to dimensions of 2.5 x 2.5 cm. Each sample was then saturated in a pressure vessel at 26.7℃(80°F) controlled to±1℃. The temperature and pressure used to saturate the specimens will be referred to as the saturation temperature and saturation pressure respectively. The saturation pressure was controlled to within ±35 kPa (±5 psi). The samples were periodically removed from the pressure vessel and weighed on a precision balance with accuracy of ±10ug to determine the amount of gas absorbed. Because the amount of gas absorbed by the samples was on the order of 10 mg, this method provided sufficient accuracy.Desorption measurements were made from fully saturated samples. After reaching equilibrium C02 concentration, the samples were allowed to desorb the C02 while held at 26.7℃(80°F) and atmospheric pressure. During the desorption experiments, the samples were weighed on a precision balance to determine the remaining C02 concentration.Foam sample preparation and characterizationSamples were cut to dimensions of 2.5 cm×2.5 cm and saturated in a pressure vessel maintained at 26.7±1℃(80°F) until an equilibrium CO2concentration was reached. The time required to reach equilibrium was determined from the sorption measurements discussed above. After saturation. all specimenswere allowed to desorb gas for five minutes prior to foaming. The same desorption time, 5 minutes, was used for all specimens to ensure that the integral unfoamed skin thickness was negligibly small. After desorption, the samples were foamed by heating in a glycerin bath for a length of time that will be referred to as the foaming time. The temperature of the glycerin bath used to foam the specimens will be referred to as the foaming temperature. All samples were foamed for five minutes. Once the foaming time had elapsed, the foamed specimens were immediately quenched in a water bath maintained at room temperature. Specific values of the saturation pressures,foaming temperatures, and foaming times will be discussed later. After foaming, the samples were immersed in liquid nitrogen and then fractured to expose the internal microstructure. The fractured surfaces were made conductive by deposition of Au-Pd vapour and then studied under a scanning electron microscope (SEM). All SEM micrographs were taken along the centre-line of the sample.Determination of cell size and cell nucleation densityThe average cell size, cell size distribution, and number of bubbles per unit volume of foam were determined by Saltikov's method described in detail by Undenvood. Saltikov's method allows the characteristics of a three dimensional distribution of spheres to be estimated from a two dimensional image, such as a micrograph. Previously it was assumed that the fracture plane passed through the centre of all bubbles in a micrograph, introducing a small error in the estimation of the average cell size. cell size distribution, and cell nucleation density. In addition, it was also assumed previously that the number of bubbles per unit volume (i.e. bubble density) could be determined by cubing the line density. Saltikov's method provides a more robust procedure for estimating the bubble density, and is applicable to a wider range of microstructures. Saltikov's method was implemented by digitizing an SEM micrograph with approximately 200 bubbles, and using NlH lmage to determine the areas of the bubbles. NIH Image is a public domain image processing and analysis program developed at the Research Services Branch (RSB) of the National lnstitute of Mental Health (NIMH), part of the National Institutes of Health (NIH). The mean bubble diameter and standard deviations reported in this paper are based on the lognormal distribution proposed by Saltikov.The cell nucleation density was determined by a method described previously and is the number of bubbles that nucleated in each cm3 of unfoamed polymer. The volume fraction of the bubbles was taken to be the area fraction of the bubbles in a micrograph as suggested by Underwood. The density of each sample was determined by the weight displacement method, ASTM D792.RESULTS AND DISCUSSIONThe solubility and diffusivity of C02 in ABSFigure 1 shows the gas sorption of CO2 into 1.5 mm thick ABS sheet subjected to saturation pressures of350 kPa, 1MPa, 2MPa, 3MPa, 4MPa, 5MPa, and 6MPa at a saturation temperature of 26.7℃(80°F). The CO2concentration in mg gas/g polymer is plotted vs time. Over time, the concentration of CO2increases within the polymer until the polymer absorbs no more gas and can be considered saturated. As expected, the concentration of gas at equilibrium increases as the saturation pressure is increased. For the ABS formulation studied here, equilibrium concentrations as high as 150 mg C02/g polymer were achieved at a saturation pressure of 6 MPa. Figure 1 also shows that the diffusion of CO2 in ABS isFigure 1 Sorption curves for 1.5 mm thick ABS in CO2 at 26.7℃(8O°F), and pressures ranging from 350kPa to 6MPa. Increasing saturation pressures result in short er saturation times and higher equilibrium concentrationsdependent on gas pressure. We see that it takes approximately 50 hours to reach equilibrium at a saturation pressure of 3 MPa, while at 6 MPa the equilibrium is reached in 20 hours. The faster diffusion at 6 MPa is a result of effective Tg of the gas-polymer system approaching the saturation temperature of 26.7℃. This isevident from Figure 5 where, for 6 MPa saturation. the onset of bubble nucleation is around 27°C.The equilibrium concentration in milligrams of C02 per gram polymer is plotted in Figure 2 as a function of the saturation pressure. The set of points in Figure 2 define the sorption isotherm for 26.7℃. Usually this isotherm can be characterized using the Dual Mode Sorption Model.In this system at 26.7℃however, a straight line passing through the origin represents all of the data accurately, and therefore Henry's Law can be used to predict the equilibrium concentration at a given saturation pressure:C=HP s(1)where C is the equilibrium gas concentration, mg/g; H is Henry's Law constant (or solubility), mg/g..MPa; and Ps is the saturation pressure, MPa.Figure 2 Sorption isotherm for C02 in ABS at 26.7℃(80°F). Note that equilibrium concentration increases linearly with saturation pressure and the linear regression passes through the origin, indicating Henry's Law is valid for a wide range of pressures in this systemFigure 2 shows that Henry's Law is valid for all of the saturation pressures explored. From a least squares fit of the data in Figure 2, the Henry's Law constant was determined to be 25.0 mg/g.MPa for a saturation temperature of 26.7℃.Figure 3 shows desorption results for ABS at 26.7℃. where the fraction of the gas remaining from the fully saturated condition is plotted as a function of time. The rate of desorption seen in Figure 5 is a function of the initial C02 concentration; increasing saturation pressure (or equivalently the equilibrium concentration) results in a faster rate of desorption. This behaviour is consistent with our observations from Figure 1 where higher saturation pressures led to significantly lower sorption times.The average diffusion coefficient, D, can be estimated from Figure 1 using the solution of the diffusion equation for a plane sheet. This diffusion coefficient is an average over the entire range of gas concentrations experienced by the sample, and is given by:2/121049.0⎪⎪⎭⎫ ⎝⎛=t D (2) Figure 3 Desorption curves for 1.5 mm ABS at 26.7℃and atmospheric conditions. The gas concentration is given as a fraction of the initial concentration. A higher initial saturation pressure results in a faster desorptionwhere t is the sorption time, 1 is the thickness of the sheet, and(t/12)1/2 is the value of t/12 when half of the equilibrium amount of gas has been absorbed. Table 1 presents the approximate time to reach saturation, and the average diffusion coefficients for C02 in ABS for different gas pressures. We see that the diffusion coefficients range from 2.14 x10-8cm2/sec for saturation at 350 kPa to 19.2 x 10-8cm2/sec at 6.0MPa. As a result of this concentration dependent diffusivity, the saturation time decreases (see Table 1) with increasing saturation pressure. from about 120 hours at 350 kPa to about 8 hours at 6.0 MPa.Conditions for steady-state structureThe objective of this portion of the study was to determine the foaming time required to produce ABS foams with a steady-state, or equilibrium, density. From the instant a saturated sample is placed in the glycerin bath, the bulk density of the specimen decreases at an ever decreasing rate until a steady sate value is achieved. After the foam density has reached steady-state, the density stops decreasing. For a given specimen thickness, the time required to reach steady-state is a function of the saturation pressure and temperature, and foaming temperature.In this experiment, samples were saturated with C02maintained at 350kPa (50.8 psi) and 22℃, and foamed at 120℃for various lengths of time. The lowest gas pressure was chosen for this experiment so as to find the longest time needed to achieve steady-state structure. The foam density as a function of foaming time is plotted in Figure 4. Recall that the density of the original. unfoamed ABS was 1.04 g/cm3. Figure 4 shows that it takes approximately 300 seconds (5 min) to reach steady-state in the ABS-C02 system for the given processing conditions. Since most other processing conditions will reach an equilibrium foam density faster than at these conditions, we used a foaming time of 300 seconds for all experiments in this study. In addition. Figure 4 shows that at a foaming temperature of 120℃, the original density is reduced by approximately 50% during the 300 seconds of foaming.Figure 4 Plot of foam density as a function of foaming time, showing that a foaming time of approximately 300 seconds is required to reach equilibrium in the ABS-C02system. Samples weresaturated at 350 kPa, allowed to desorb for 5 minutes, then foamed at 120°CThe effect of saturation pressure and foaming temperatureTo explore the effect of foaming temperature and saturation pressure on microstructure, samples were saturated at different pressures and then foamed over a range of temperatures. After the samples had been produced, the foam density, average cell size, cell size distribution, and cell nucleation density were determined.Figure 5 shows a plot of the relative density (density of the foam divided by the density of the solid material) as a function of foaming temperature for the saturation pressures explored. A wide range of relative densities can be produced in the ABS-C02 system. Foams can be produced with relative densities from 0.99 (i.e. almost fully dense) to as low as 0.09. In addition, most densities can be produced by using more than one processing condition. In other words, different saturation conditions and foaming temperatures can be used to produce the same density foam. Similar to other microcellular systems, Figure 5 shows that foaming can occur in ABS at temperatures significantly below the glass transition temperature of the unsaturated material due to plasticizing of the polymer matrix by the absorbed C02. As the saturation pressure is increased, the effective glass transition temperature drops, allowing foams to be producedFigure 5 Process space for the ABS-CO2, system, showing a plot of the relative density as afunction of foaming temperature for saturation pressures from 350kPa to 6MPa. All samples were saturated at 26.7℃. allowed to desorb for five minutes before foaming, then foamed for five minutes. The useful part of the process space lies to the left of the minimum density for a given gas pressureat lower temperatures. At a saturation pressure of 6 MPa. Figure 5 shows that foaming is possible at approximately 27℃, just above room temperature.The relative density of microcellular ABS is affected strongly by the foaming temperature. As the foaming temperature increases, the relative density decreases in near linear proportion. The fact that relative density decreases nearly linearly with foaming temperature is a great processing advantage. allowing precise control over this vital foam property. As the foaming temperature increases, the foam density reaches a minimum, and can start to increase with increasing temperature. At 5 MPa, Figure 5 shows that using foaming temperatures higher than 100℃produces foams with a higher relative density. At 140℃, for example, a relative density of approximately 0.8 is produced, significantly higher than the relative density of 0.3 produced at a foaming temperature of 100℃. At higher temperature, the cells begin to collapse leading to a denser structure. Foams produced at these higher temperatures are typically of poor quality, with 1 to 2 mm blisters on the surface. This minimum in the density versus foaming temperature can be observed at several other gas pressures in Figure 5.Figure 6 shows SEMs of four different microcellular ABS foams. The first two images, A and B, demonstrate the large effect of saturation pressure on foam density and cell size. Figure 6 A and B wereproduced with different saturation pressures, 3 and 6 MPa respectively, but the same foaming temperature of 70℃. The foams in A and B have relative densities of 0.70 and 0.42 respectively. The cell sizes vary from approximately 5 um for A to less than 1 um for B. Images C and D in Figure 6 show two foams produced from the same saturation pressure, 350 kPa, but foamed at different temperatures, 105 and 120℃. The foams have relative densities of 0.88 for C and 0.31 for D and show markedly different foam structures.Table 2 presents the results of the scanning electron micrograph analysis, and shows it is possible to produce microcellular ABS foams with a wide range of cellular properties. Not all foams were suitable for analysis using Saltikov's method. To be suitable for analysis, the foam structure should have spherical cells, and the cells must be distinct in the micrograph. For example, in Figure 6 images A and C can be analyzed, while B and D can not. Thus the test pressures and foaming temperatures not reported in Table 2 are the conditions that produced cells not suitable for a Saltikov analysis. The measured average cell diameters in Table 2 vary from 5.58 pm to 0.54 pm, and the cell nucleation density ranges from 4.0 x 1 010 to 1.8 x 1013 cells per cm3. Microcellular ABS foams generally have small cell sizes and high cell nucleation densities.Figure 6 Micrographs of four different microcellular ABS foams. A and B were saturated at different pressures, 3 MPa and 6 MPa respectively, but were foamed at the same temperature, 70℃. C and D were both saturated at the same pressure, 350 kPa, but were foamed at different temperatures, 105 and 120℃, respectively. All samples were allowed to desorb for five minutes before being foamed for five minutesCONCLUSIONSProcessing conditions have been presented for producing solid-state microcellular ABS foams using carbon dioxide as the blowing agent. It was found that, at a given temperature, the rate of C02 sorption and desorption in ABS is dependent on the gas concentration. It was also discovered that the ABS-C02 system exhibited a unique microstructure with a relatively narrow distribution of bubble sizes. An experimentalinvestigation of the major processing variables, foaming time, saturation pressure, and foaming temperature yielded several insights into the processing behaviour of the ABS-C02 system. It was determined that it takes a maximum of approximately 300 seconds for foam growth to complete. It was also determined that, for all saturation pressures explored, foam density decreases nearly linearly with increasing foaming temperature until a minimum density is reached. Foams with densities ranging from 0.09 g/cm3 to almost fully dense, 1.03 g/cm3 were produced. The useful range of process space for the ABS-C02 system was established.ACKNOWLEDGEMENTSThis research was primarily supported by the University of Washington-Industry Cellular Composites Consortium. Partial support was provided by National Science Foundation Grant MSS 9114840. This support is gratefully acknowledged.1. Brisimitzakis A.C., Styrenic resins - ABS, Modern Plastics, 68,(1991), 85-86；2. Martini J.E.. Suh N.P. and Waldman F.A., The Production and Analysis of Microcellular Thermoplastic Foams, Society of Plastics Engineers Technical Papers, XXVIII, (1982), 674-676；3. Kumar V. and Schirmer H.G., Semi-continuous Production of Solid State PET Foams, Society of Plastics Engineers Technical papers, XLI, (1995), 2189-2192；4. Kumar V. and Schirmer H.G., A Semi-continuous Process to Produce Microcellular Foams, US Patent 5,684.055 (1997)；5. Kumar V. and Weller J.E., A Model for the Unfoamed Skin on Microcellular Foams. Polymer Engineering and Science, 34, (1994), 169-173；6. Kumar V. and Weller J.E., Production of Microcellular Polycarbonate Using Carbon Dioxide for Bubble Nucleation, Journal of Engineering for Industry, 116. (1994). 413-420；7. Handa V.P.. Wong B., Zhang Z., Kumar V., Eddy S. and Khemani K., Some Thermodynamic and Kinetic Properties of the System PETG-C02, and Morphological Characteristics of the C02-Blown PETG Foams, Polymer Engineering and Science, 39, (1999), 55-61；8. Kumar V. and Stolarczuk P.J., Microcellular PET Foams produced by the Solid State Process, Society of Plastics Engineers Technical Papers. XLII, (1996). 1894-1899；9. Kumar V. and Weller J.E., A Process to Produce Microcellular PVC, International Polymer Processing, 7, (1993), 73-80；10. Shimbo M., Baldwin D.F. and Suh N.P., Polym. Eng. Sci., 35, (1995), 1387；11. Park C.B. and Suh N.P., Polym. Eng. Sci., 36, (1996), 34；12. Collias D.I., Baird D.G. and Borggreve R.J.M., Polymer, 25, (1994), 3978；13. Underwood E.E.. Quantitative Stereology, Adison-Wesley, Reading, Massachusetts, (1970)；14. Michaels A.S., Vieth W.R. and Barrie J.A., Solution of Gases in Polyethylene Terephthalate, Journal of Applied Physics, 34, (1963),1-12；15. Crank J.. The Mathematics of Diffusion, Oxford University Press,New York (1975)。
材料成型及控制工程专业英语--1.MATERIALS-AND-THEIR-PROPERTIES
1.1 Metals and Non-metalsWords and termsdefinite－确定的、明确的defect－缺陷plastic deformation塑性变形stress concentrator 应力集中点self-strengthening自强化the tip of a crock裂纹尖端☐Among numerous properties possessed by materials，their mechanical properties，in the majority of cases，are the most essential and therefore，they will be given much consideration in the book．☐在一些主要应用场合，机械性能是材料的各种性能中最重要的性能，因此，本书中将重点讨论。
▪consideration 考虑，需要考虑的事项，报酬☐All critical parts and elements，of which a high reliability （可靠性）is required，are made of metals, rather than of glass，plastics or stone.☐由于各种关键零部件的可靠性要求高，均用金属而不是玻璃、塑料或石头制造。
▪is required 翻译时将英文中的被动语态，改译为汉语中的主动语态。
▪rather than 而不是☐As has been given in Sec.1-1，metals are characterized by the metallic bond（金属键），where positive ions （正离子）occupy the sites of the crystal lattice （晶格）and are surrounded by electron gas（电子云）．☐正如Sec1-1中所说，金属主要由金属键组成（其特征主要……）。
材料成型及控制工程专业英语及翻译解读
最新消息1-2the benefits of civilization which we enjoy today are essentiallydue to the improved quality of products available to us .文明的好处我们享受今天本质上是由于改进质量的产品提供给我们。
the improvement in the quality of goods can be achieved with proper design that takes into consideration the functional requirement as well as its manufacturing aspects. 提高商品的质量可以达到与适当的设计,考虑了功能要求以及其制造方面。
The design process that would take proper care of the manufacturing process as well would be the ideal one. This would ensure a better product being made available at an economical cost.设计过程中,将采取适当的照顾的生产过程将是理想的一个。
这将确保更好的产品被使可得到一个经济成本。
Manufacturing is involved in turning raw materials to finished products to be used for some purpose. 制造业是参与将原材料到成品用于某些目的。
In the present age there have been increasing demands on the product performance by way of desirable exotic properties such as resistance to high temperatures, higher speeds and extra loads.在现在的时代已经有越来越多的产品性能要求的理想的异国情调的性能如耐高温,更高的速度和额外的负载These in turn would require a variety of new materials and its associated processing.这些反过来需要各种新材料及其相关的处理Also, exacting working conditions that are desired in the modern industrial operations make large demands on the manufacturing industry.这些反过来需要各种新材料及其相关的处理。
材料成型及控制工程专业的专业英语翻译
polystyrene (PS) 聚苯乙烯；poly-tetra-fluoro-ethylene （PTFE）聚四氟乙烯；vacuum forming吸塑；ram injection moulding machine柱塞式注射成型机；计算机辅助设计computer aided design；热塑性塑料thermoplastics；ram injection moulding machines；模具维持费用；聚合物分子的几何形状the geometrical form of polymer molecule；模具设计die design；注射成型机injection moulding；热处理heart treatment；抗拉强度tensile serength；对焊buttwelding；自由锻open die forging；粉末冶金powder metalurgy；注射模塑injection molding；线状聚合物linear polymer；球化spheroidzing；正火normalizing；回火tempering；临界温度critical temperature。
1. The time has probably come to adapt a new name more worthy of the exciting range of polymer materials with many different properties which are available to engineers.目前塑料定义已可能迎来新的术语，以阐述具有不同属性可用于工程领域的聚合物材料。
2.It should be noticed that compression moulding would be impracticable for thermoplastics which have no curing stage during which a chemical reaction take place; because the mould would require cooling each cycle in order to allow the component to harden sufficiently for extraction. 需要指出的是，热塑性塑料压缩成型是不可行的。
材料成型及控制工程外文翻译文献
材料成型及控制工程外文翻译文献(文档含英文原文和中文翻译)在模拟人体体液中磷酸钙涂层激光消融L. Cle`ries*, J.M. FernaHndez-Pradas, J.L. Morenza德国巴塞罗那大学,西班牙1999年七月二十八日-2000年2月文摘:三种类型的磷酸钙涂层基质,在钛合金激光烧蚀技术规定提存,沉浸在一个模拟的身体# uid为了确定条件下他们的行为类似于人的血浆。
羟基磷灰石涂层也也非晶态磷酸钙涂层和a-tricalcium磷酸盐做溶解阶段b-tricalcium磷酸盐的涂料有细微的一个阶段稍微瓦解。
一个apatitic阶段降水量偏爱在羟基磷灰石涂层的涂料磷酸b-tricalcium上有细微的一个阶段。
在钛合金基体上也有降水参考,但在大感应时代。
然而,在非晶态磷酸钙涂层不沉淀形成。
科学出版社有限公司(2000保留所有权利。
关键词:磷酸钙,脉冲激光沉积,SBF1 介绍激光消融技术用于沉积磷酸钙涂层金属基体上,将用作植体骨重建。
用这个技术,磷酸钙涂层量身定做阶段和结构也成功地研制生产了[1,2]和溶解特性鉴定海洋条件]。
然而,真正的身体条件# uid饱和对羟基磷灰石的阶段,这是钙离子的浓度高于均衡的这个阶段。
因而,这就很有趣也测试条件磷酸钙涂料接近体内的情况,以了解其完整性,在这些条件及其催化反应性质}表面沉淀过程。
因此,非晶态磷酸钙涂层(ACP),羟基磷灰石(HA)涂层,涂层中的一个阶段b-tricalcium磷酸盐较小(ba-TCP)积下激光烧蚀是沉浸在饱和溶液为迪!时间、不同的结构性演变进行了测定。
饱和溶液的使用的是身体uid(SBF模拟#),解决了其离子浓度、酸碱度几乎等于那些人类血浆[5]。
该解决方案也是一个利用在仿生(沉淀)工艺生产磷灰石层在溶胶凝胶活性钛基体。
2 实验模拟身体化学溶解试剂级严格依照以下的顺序,除氢钠,NaHCO3:)3,K2HPO4 H2O,MgCl2)6 H2O,氯化钙和Na2SO4)2 H2O,在去离子水。
材料成型及控制工程专业英语
A an ionic or a covalent bond离子或共价键at the tip of a crack裂纹尖端as a practical matter 根据实际情况alloy composition合金浓度absence缺乏alloying element合金元素high/low alloy steels高低合金钢austenitic奥氏体antimony锑austenite to pearlite奥氏体到珠光体axis 纵坐标abscissa横坐标a coarse grained 粗大晶粒annealing 退火Account for解释Activation energy活化能Anchor抛锚Austenitic grains奥氏体成状结构Actual grain size 实际晶粒An anchor for the backing material of the mold 一个模具的基底材料的锚B beam梁bar棒材brittleness脆性bend of 变弯曲Be about linear关于线性Bring about造成Binder粘合剂Brittleness脆性Be attributed to 归因于……Be extremely abrasive to punches 对凸模非常耐磨C Cast irons铸铁corrosion resistance合金浓度critical part and element关键零部件corrosion resistance耐磨性crystal lattice晶格charges电荷carbon content含碳量corrosion atmosphere腐蚀环境chromium铬corrosion腐蚀crystalline fracture结晶断面cementite碳化铁crucibles坩埚catalytic converters催化转换器cementite 渗碳体concentration 集中carburizing 渗碳critical rate 临界速度Carbonitrides碳氮化物Carbides碳化物Cell size晶胞大小Cell misorientation细胞取向差Casting铸造Centrifugal casting离心铸造Coarse-grained silica粗大晶粒的二氧化硅Concentrate聚集浓缩Creep strength蠕变强度Cooling rate冷却Crystallization 结晶Combustion燃烧Constitutional diagram状态图Constituents组份Chain-like链状Coarsening of Austenite grains粗化奥氏体晶粒D defect缺陷deoxidation去氧ductile易延展的designation名称deformation变形dislocation motion位错运动high/low ductility塑性ductile iron球墨铸铁，韧性铁ductility韧性die castings压铸dental alloys牙齿的合金Depends v. 依赖disperse 分散depletion 消耗尽decomposes分解diffusionless martensite transformation 无扩散马氏体转变Deformed elongated structure变形细长结构Dislocation cell formation位错胞的形成Dislocation density位错密度Dynamic recrystallization 动态再结晶Static recrystallization静态再结晶Ductility and toughness塑性（延展性）和韧性Distortion 变形（畸变）Depends依赖Deformability可变形性Diminishes减小Diffusion扩散Decomposition 分解Diffusion扩散Deformability n. 可变形性Diminishes减小Diffusion扩散Decomposition分解E Exceed超越electrostatic attraction静电吸引electrical conductivity导电性electronics industry 电子产业Equilibrium平衡electron microscope 电子显微镜Evacuated排空的Embrittling impurities 杂质脆化Equiaxed等轴的，各项等大的Eddy current losses涡流耗损Equilibrium平衡F Fracture断裂ferrous alloys铁合金forging锻造ferrite铁素体heat resistant alloys耐热合金formability可成形性forged锻造的fabrication制造fabrication制造Foams v. 起泡沫Fabrication制造Fine grains小晶粒Formation of Austenite 奥氏体形成Ferrite gain铁氧体收益Flow stress流变应力Flask型腔Fine，equiaxed grains细小等轴晶粒Fluid tightness液体密闭性Fatigue strength疲劳强度Foams起泡沫Fabrication制造Fine grains小晶粒Formation of Austenite 奥氏体形成G General-purpose plain steels普通钢gray iron灰铸铁finely faceted细面的graphite石墨galvanization通流电Grains成状结构granular粒状的Grain boundary strengthening晶界强化Grain growth颗粒增长H Hot-rolled steel热轧钢higher strength高强度hardness硬度hot working热处理Heating temperature加热温度Homogeneous austenite均匀奥氏体homogeneous均匀hypereutectoid 过共析体hypoeutectoid 亚共析体hypoeutectoid ferrite 亚共析铁素体hypereutectoid cementite 过共析渗碳体Hinged and fastened with a screw device用螺纹设备来连接并固定I Bad Impurities有害杂质immense极大的inferior较低的Inhomogeneous 不平均Inherent fine grained本质粗大晶粒Incubation period 孕育期Is accompanied with 伴随着Interrupted 中断打断incubation period 孕育期isothermal decomposition ofaustenite 奥氏体的等温转变Internal cavitation and fracture behaviors内部的气穴现象和断裂行为Investment molds 熔模铸造Invert倒置In wrought form按照加工的形式impaire损害J justificationL less liable to grain coarsening 晶粒粗化不易lamellar薄片状的left hand curve左边的曲线logarithmic 对数lamellar structure 层状结构Lubricant润滑剂Lost wax process失蜡铸造法M Mechanical property机械性能martensite马氏体malleable可塑的molten metal金属液molybdenum钼Molecules 分子Macromolecules 大分子measure of its stability 衡量它的稳定性Metallographic examination of quenched specimens淬火试样的金相检验N Nitrites亚硝酸盐类niobium铌Nucleation of pearlite珠光体形核normalizing正火Nitrides氮化物O Oxidation氧化ore reserves矿藏量oxides氧化物Overheat 过热P Plasticity塑性plastic deformation塑性变形precipitation-hardening steels沉淀硬化钢phase 相properties性能porosity多孔precipitates析出物，沉淀物passivation钝化作用platinum coatingsPearlitic grain 珠光体Pearlite（ferrite+cementite）珠光体是有铁素体和渗碳体组成的Pearlite transformation珠光体表面Polymers 聚合物Polymerization 聚合物白金涂料Pinning of subboundaries钢钉的分界限Plastic flow塑性流动Plastic-bonded shell molds塑性粘结壳型Plaster molds 石膏模Pour into 倒入Precision-cast精铸Precision精度Q Quench冷却quasi-eutectoid 伪共析R Rolling mill轧钢厂resistance阻力radiators散热器rival竞争的radiation shielding辐射防护层Rigidity of刚性的Retarded 迟钝的Retarded adj. 智力迟钝的recrystallization再结晶Retention保留Recovery 回火Recrystallized再结晶Replica复制品Refractory material耐火材料S Structural materials结构材料self-strengthening自强化stress concentrator应力集中点state standard国家标准stamping冲压sheet板材stainless steels不锈钢springs弹性shrinkage减少spheroidal球状的solution hardening固溶淬火solubility可溶性Single grain 单晶Spontaneous 自发sorbite索氏体superposition重叠structural 结构strain hardened 应变强化saturation 饱和Softening软化Stored energy储存的能量Stress 应力Strain rate应变率Subgrain and dislocation strengthening亚晶和位错强化Superplasticity超塑性Static recovery静态恢复Strain rate应变率Stress strain应力应变Strength and stiff 强度和硬度Stress rupture应力破坏，应力断裂Surface finish 表面光洁度Setting and firing固化Sand is rammed or packed沙子是冲压和晒满的T Thermal保热的tenacious紧密的tensile strength抗拉强度tantalum钽tungsten钨The liability of austenite to grain coarsening趋向The final grain size最终晶粒尺寸The rate of transformation 转变温度The rate of nucleation 形核速度The rate of crystal晶核Thermoplastic polymers热塑聚体Transparency 透明的troostite 屈氏体tempering 回火Torsion扭转tension拉伸compression 压缩Two orders of magnitude两个数量级Thermally activated热启动Thermosetting resin热固性树脂Tolerance公差U Undercooling 过冷undercooled austenite 过冷奥氏体undercool过冷V Viscosities粘度vanadium钒W Weight reduction测量结构wrought alloys可锻合金welding焊接Work hardening 加工硬化Wooden pattern 木制的模板Withdrawn取出Wax蜡烛Weakness缺点Y Yield屈服Yield strength屈服强度。
材料成型及控制工程外文文献翻译
本科毕业论文外文文献及译文文献、资料题目：The effects of heat treatment onthe microstructure and mechani-cal property of laser melting dep-ositionγ-TiAl intermetallic alloys 文献、资料来源：Materials and Design文献、资料发表（出版）日期：2009.10.25院（部）：材料科学与工程学院专业：材料成型及控制工程班级：姓名：学号：指导教师：翻译日期：2011.4.3中文译文：热处理对激光沉积γ-TiAl金属间化合物合金的组织与性能的影响摘要：Ti-47Al-2.5V-1Cr 和Ti-40Al-2Cr (at.%)金属间化合物合金通过激光沉积（LMD）成形技术制造。
显微组织的特征通过光学显微镜（OM）、扫描电子显微镜（SEM）、投射电子显微镜（TEM）、和X射线衍射仪（XRD）检测。
沿轴向评估热处理后的沉积试样室温下的抗拉性能和维氏硬度。
结果表明：由γ-TiAl 和α2-Ti3Al构成的γ-TiAl基体试样具有全密度柱状晶粒和细的层状显微组织。
Ti-47Al-2.5V-1Cr基体合金和Ti-40Al-2Cr基体合金沿轴向的室温抗拉强度大约分别为650 MPa、600MPa，而最大延伸率大约为0.6% 。
热处理后的Ti-47Al-2.5V-1Cr和Ti-40Al-2Cr合金可以得到不同的显微组织。
应力应变曲线和次表面的拉伸断裂表明沉积和热处理后的试样的断裂方式是沿晶断裂。
1.简介金属间化合物γ-TiAl合金由于其高熔点（﹥1450℃）、低密度（3g/cm3）、高弹性模量（160-180GPa）和高蠕变强度（直到900℃）成为很有前景的高温结构材料，一直受到广泛研究[1–4]。
但是对于其结构应用来说，这种材料主要缺点之一是在室温下缺少延展性。
此外，这种合金运用传统的制造工艺诸如锻压、轧制和焊接，加工起来比较困难[5]。
材料成型专业外文翻译文献
Optimal mould design for the manufacture by compression moulding of high-precisionlensesM. Sellier†1, C. Breitbach†, H. Loch† and N. Siedow‡August 7, 2006† Schott AG, Hattenbergstrasse 10, 55122 Mainz, Germany‡ Fraunhofer-Institut fuer Techno- und Wirtschaftsmathematik (ITWM)Fraunhofer-Platz 1, 67663 Kaiserslautern, GermanyAbstractThe increasing need for low-cost, high-precision optical devices requires innovative manufacturing techniques or the optimization of existing ones. The present study focuses on the latter alternative and proposes a computer-aided, mould optimization algorithm for the manufacturing of high-precision glass lenses by compression moulding. The intuitive, yet very efficient, algorithm computes at each optimization loop the mismatch between the desired and deformed glass shapes and uses this information to update the mould design. To solve this optimal shape design problem, a finite element model representative of the real industrial process is developed and solved in the commercial package ABAQUS. This model solves the several stages involved in the process and includes the thermo-mechanical coupling, the varying mechanical contact between the glass and the mould, and the stress and structure relaxation in the glass. The algorithm is successfully tested for the mould design for a plano-concave and a bi-concave lens as the residual error between the deformed and desired glass profiles is decreased to a value of the order of one micron.Keywords: optimal shape design, compression moulding, glass forming, finite element model.1 mathieu.sellier@itwm.fhg.de1.IntroductionIn the competitive industry of optics manufacturing, there is a growing need for the mass production of high-precision glass parts. To date, however, there is still a conflict between the productivity and accuracy requirements. Indeed, existing techniques relying on the grinding and polishing of the moulded glass piece can achieve sub-micron accuracy but at a prohibitive cost. A much more time- and cost-effective alternative would be to predict directly the mould design which yields the net, desired glass shape at the end of the forming process without requiring further post-processing.The compression moulding process, illustrated in Figure 1, consists of three stages: heating of the glass preform/mould assembly to a temperature above the glass transition temperature, pressing of the softened glass to transfer the mould shape onto the glass and, cooling down to room temperature. The mould design in this process is a challenging task because of the deformations induced during cooling stage (thermal shrinkage, residual stresses). Although the profile of the mould might be perfectly transferred to the softened glass at the end of the pressing stage, a strategy is required to compensate for these deformations. Existing compensation techniques rely, according to Yi and Jain in [1], on a simple first-order theory of thermal expansion but such an approach comes to a limit when accuracy of the order of one micron is targeted. Other studies related to the computer-aided tool design for glass forming include, for example, that of Moreau et al. in [2] who optimize the press design in the forming of an automotive rear side panel, that of Lochegnies et al. in [3] who determine the required mould yielding a prescribed glass thickness distribution in the blow and blow process, or that of Agnon and Stokes in [4] who derive the former shape that produces a prescribed top surface curvature profile in the thermal replication process.The aim of the present work is to present a numerical algorithm to optimize the mould shape in the context of high-precision compression moulding and demonstrate its ability toproduce challenging lens designs with an accuracy of the order of one micron. The intuitive idea of the algorithm is to iteratively “test and correct”. The residuals giving a measure of the mismatch between the final and desired glass piece geometries are computed at each optimization loop and used to update the previous mould design.The next section is devoted to the description of the process and its modelling in the finite element package ABAQUS. The details of the computer-aided mould optimization algorithm follow. Lastly, results supporting the success of the method for the mould design for a plano-concave and a bi-concave lens shape are reported.2.Modelling of the processThe first requirement to tackle numerically the optimal shape design problem described above is to be able to model accurately the forward problem, i.e. “what is the final glass profile for a given mould design?” Modelling the entire process is a complicated task because of the many stages involved, the thermo-mechanical coupling, the varying mechanical contact between the glass and the mould, and the complex rheology of the glass. To reduce the computational cost, only a simplified model representative of the whole industrial process is considered. The model is solved in the commercial finite element package ABAQUS and user-defined subroutines were developed to implement the complex rheology of the glass. Since the forming temperature is slightly above the glass transition temperature, the glass is in the viscoelastic range and the combined effects of stress and structure relaxation must be accounted for in order to achieve the necessary accuracy. The glass behaviour is represented by the Tool-Narayanaswamy model, [5, 6]. This model has become a standard to handle stress relaxation in glassy materials under non-isothermal conditions. The interested reader is referred to [8] for a thorough description of the model and to [7] for an overview. It suffices here to say that the glass has a transition temperature of 505 °C. Other glass properties and relaxation parameters are not reported since the optimization method described is entirely based ongeometric considerations and its success is therefore independent of the precise material properties or operating conditions. The mould is modelled in ABAQUS as a rigid body since its stiffness is much greater than that of the glass.The finite element analysis is restricted to an axisymmetric geometry and only a two-dimensional radial cross section of the model is represented in Figure 2 for the plano-concave lens and in Figure 3 for the bi-concave one. The glass preform is enclosed in the upper and lower parts of the mould and the outer ring prevents it from flowing outwards during the pressing stage. The outer ring is simply represented in ABAQUS by a rigid surface since its influence on the overall process is minor. In the real industrial process, the glass preform is produced in a low-cost, low-precision, preliminary stage with a near optimal shape and volume. For the plano-concave case, the preform has a flat lower surface and a spherical, concave upper one of radius of 44 mm. This radius is 10% greater than that of the desired final lens design (40 mm). For the bi-concave lens design, the upper and lower preform surfaces are both spherical and concave with a radius of 44 mm which is again 10% greater than the radii of the desired lens design.The thermo-mechanical coupling is included in the three stages of the transient analysis (heating, pressing, and cooling) but the effects of radiative heat transfer are neglected. The required symmetry conditions are imposed along the axis and the nodal vertical displacements are prescribed to vanish on the lower side of the lower mould (see the boundary conditions on the left-hand side of Figures 2 and 3).The glass and both parts of the mould are initially in contact along the axis. Thermal boundary conditions of the Dirichlet-type are applied on the top of the upper and the bottom of the lower mould and the lateral walls of the moulds are assumed to be insulated. All other boundaries are grouped in contact pairs. For the two surfaces of a contact pair, which don’t necessarily have to be in contact, mechanical and thermal surface interaction models are defined. In this set-up two nodes of the contact pair surfaces 1 and 2 exchange heat fluxes perunit area taking into account surface to surface radiation and heat conduction through the air layer between the two surfaces.The heating stage consists of imposing a steadily increasing temperature on the upper side of the upper mould and the lower side of the lower one (time-dependent Dirichlet boundary conditions). The temperature rises from 50 °C to 600 °C in 180 s and then remains constant for 180 s to reach a uniform temperature field. This temperature is about 95 °C above the glass transition temperature, a sufficiently high temperature to shape the glass preform. During this stage, the upper mould is moved upwards by a small amount to allow the glass to expand freely.In the pressing stage, the temperature is held constant at 600 °C and a downward stroke is imposed on the upper mould. The value of the displacement is chosen so that the lens thickness at the centreline is equal to the desired one. The displacement is ramped linearly in a time interval of 360 s. At the end of the pressing stage, the mould shape is transferred onto the mould.Finally, the temperature at both ends of the glass and mould assembly is decreased from 600 °C to 20 °C in 360 s during the cooling stage. This steady cooling is followed by a period of 180 s during which the temperature is kept at 20 °C. The position of the mould is held constant during this stage and a gap between the glass and the mould appears and grows because of the thermal shrinkage and the residual stresses in the glass. The right-hand side of Figures 3 and 4 shows the glass/mould assembly at the very end of the forming process when the desired glass profile is given to the mould. Although the magnitude of the gap is small in magnitude, the consequent mismatch between the contour of the glass piece and the one of the closed mould needs to be compensated for if an accuracy of the order of one micron is targeted.3.Description of the mould optimization algorithmThe optimization algorithm described in the following ignores the very details of the compression moulding process. It simply considers it as an operator F which maps the initialmould contour j mC into the final glass shape j g C at iteration j (see Figure 4). Although the glass contour is a closed curve, the upper and lower curves are considered independently in the range[0]i r ,. The curves are represented, in the scientific computing program MATLAB, bycubic splines fitted through the nodes of the mesh. Introducing the arc-length s , the curves j mC and j g C are defined in parametric form by the points ()()()j j m m r s z s , and ()()()j j g g r s z s ,,respectively, in intervals of s to be defined. Moreover, the initial glass contour 0C and thatdesired d C are described by the points ()00()()r s z s , and ()()()d d r s z s ,, respectively. The total length of the initial glass contour in the r -range of interest ([0]i r ,) is denoted by i l and iscomputed according to 122001i r i dz l dr dr /⎛⎞⎛⎞=+.⎜⎟⎜⎟⎜⎟⎝⎠⎝⎠∫ (1) The end point of the initial glass contour ()00()()i i r l z l , is displaced to ()()()()000000()()()()()()j j e e i r i i i z i i r z r l u r l z l z l u r l z l ,=+,,+, in the deformed glass geometry, where ()()()j j r z u r z u r z ,,, is the displacement vector at the location ()r z , and iteration j . Thus, the length i l in the initial glass geometry becomes j e l in the deformed geometry with 12201e j r gj e dz l dr dr /⎛⎞⎛⎞⎜⎟=+.⎜⎟⎜⎟⎜⎟⎝⎠⎝⎠∫ (2) The curves j m C ,j g C ,d C , and 0C are now completely defined by the points ()[0]()()i j j m m s l r s z s ∈,,, ()[0]()()j e jj g g s l r s z s ∈,,,()[0]()()j e d d s l r s z s ∈,,, and ()00[0]()()is l r s z s ∈,,, respectively. These curves are split into N equal intervals and the optimization loop proceeds on the 1N + corresponding control points.Although the operator F can not be completely characterized, two features, illustrated in Figure 4, may be expected and assumed:1. A point i P initially located at ()00()()i i r s z s , on the glass surface will be locatedaround ()()()j j i g f g f G r s z s =, in the deformed glass geometry (here,i l i Ns i =, j e l f N s i = and the index i ranges from 0 to N ). For example, a point located halfway through the initial glass contour may be expected to be located halfway through the deformed glass contour providing the curves remain reasonably smooth.2. The modification of the mould at ()()()j j i m i m i M r s z s =, only has a local effect on the initial glass surface at ()00()()i i i P r s z s =,.Based upon these assumptions, one can build a one to one operator F between ()()()j j m i mi r s z s , and ()()()j j g f g f r s z s ,, i.e.:()()()()j j g f m i j j g f m i r s r s F z s z s ⎧⎫⎧⎫⎪⎪⇒,⎨⎬⎨⎬⎪⎪⎩⎭⎩⎭ (3)and construct an iterative scheme to identify the required mould geometry as follows 11()()()()j j j m i r f m j j j m i z f m r s s r z s s z +⎧⎫⎪⎪⎪⎪⎨⎬⎪+⎪⎪⎪⎩⎭⎧⎫+Δ⎪⎪=,⎨⎬+Δ⎪⎪⎩⎭(4)where()()()()()()j j r f d f g f j j z f d f g f s r s r s s z s z s ⎧⎫⎧⎫Δ−⎪⎪⎪⎪=,⎨⎬⎨⎬Δ−⎪⎪⎪⎪⎩⎭⎩⎭ (5)is the residual vector. After updating the location of the 1N + control nodes on the mould surface, the mesh of the upper and lower mould contour is reconstructed.4. Mould design resultsThe optimization algorithm is applied to identify the required mould design which yields the desired plano-concave and bi-concave lenses described in the previous section. The mould design is optimized up to a radius r i of 18 mm and the number of intervals N is chosen equal to20. The only requirement on the number of nodes is that the number of control nodes should be sufficient to describe the curves accurately. The desired glass profile at room temperature is chosen as a first guess for the required mould shape. At each optimization loop, the same downward displacement which yields the desired centreline thickness is imposed on the upper mould and all other forming parameters apart from the unknown required mould contours remain identical.Figures 5 and 6 plot the nodal distance from the desired to the deformed glass profiles, in the direction normal to the desired profile, for the bi-concave and the plano-concave lens designs, respectively. Of course, as the nodal residuals become smaller, the mismatch between the deformed and desired glass geometries decreases. These two figures confirm the success of the optimization algorithm since the best mould design from a total of 6 loops, allows a substantial drop in the average value of the nodal residuals and the micron target is almost achieved everywhere. Indeed for the flat surface of the plano-concave lens design, a reduction of the nodal residuals of almost two orders of magnitude is achieved. Iterating further does not reduce further the residuals as these become oscillatory, i.e. regions of decreasing and increasing residuals alternate. Finally, Figure 7 shows the lower profile of the plano-concave lens at the end of the process for each optimization loop. This figure clearly illustrates that this surface becomes flatter and flatter, and therefore gets closer and closer to the desired design, as the optimization algorithm proceeds.5.ConclusionsA computer-aided optimization algorithm is presented in this paper for the mould design in high-precision compression moulding. Only a simplified model representative of the real industrial process is solved in the commercial finite element package ABAQUS. This model takes into account the multi-stage nature of the process, the thermo-mechanical coupling, the varying mechanical contact between the glass and the mould, and the complex rheology of theglass. The intuitive concept of the algorithm consists of computing at each optimization loop the mismatch between the final and desired lens profiles and using this information to update the previous mould design. Results for the mould design for a plano-concave and a bi-concave lens design confirm the feasibility of the method and its fast convergence rate. Indeed, only a few iterations are necessary to reduce the mismatch between the deformed and desired glass shapes to the targeted value of one micron. Although the true success of the optimization algorithm can only be assessed when applied to the real industrial process, this could provide a valuable alternative to other mould compensation technique. AcknowledgementsThe authors gratefully acknowledge the funding of the European Union through the MAGICAL project.References[1] Yi, A.Y. and Jain, A. Compression molding of aspherical lenses-a combined experimental and numerical analysis. J. Am. Ceram. Soc., 2005, 88, 579-586.[2] Moreau, P., Lochegnies, D. and Oudin, J. Optimum tool geometry for flat glass pressing. Int. J. Form. Proc., 1999, 2, 81-94.[3] Lochegnies, D., Moreau, P. and Guibaut, R. A reverse engineering approach to the design of the blank mould for the glass blow and blow process. Glass Technol., 2005, 46, 116-120. [4] Agnon, Y. and Stokes, Y.M. An inverse modelling technique for glass forming by gravity sagging. Eur. J. Mech. B-Fluids, 2005, 24, 275-287.[5] Tool, A.G. Relation between inelastic deformation and thermal expansion of glass in its annealing range. J. Am. Ceram. Soc., 1946, 29, 240-253.[6] Narayanaswamy, O.S. A model of structural relaxation in tempering glass. J. Am. Ceram. Soc., 1971, 54, 491-498.[7] Scherer, G.W. Relaxation in glass and composites, Wiley, New York, 1986.[8] Sellier, M. Optimal process design in high-precision glass forming. Int. J. Form. Proc., 2006, 9, 61-78.Figure captionsFigure 1: Schematic view of the compression moulding process with the corresponding temperature treatmentFigure 2: Two-dimensional radial cross section of the finite element model of the glass/mould assembly for the plano-concave lens in the initial (left) and deformed (right) configurationsFigure 3: Two-dimensional radial cross section of the finite element model of the glass/mould assembly for the bi-concave lens in the initial (left) and deformed (right) configurationsFigure 4: Schematic description of the algorithm and the operator F which transforms the initial mould geometry into the final glass oneFigure 5: Normal distance (in mm) between the desired and deformed glass profiles in a direction normal to the desired profile for each of the control nodes and for the bi-concave lens designFigure 6: Normal distance (in mm) between the desired and deformed glass profiles in a direction normal to the desired profile for each of the control nodes and for the bi-concave lens designFigure 7: Lower lens profile at each optimization loop for the plano-concave designFigure 1: Schematic view of the compression moulding process with the corresponding temperaturetreatmentFigure 2: Two-dimensional radial cross section of the finite element model of the glass/mould assembly for the plano-concave lens in the initial (left) and deformed (right) configurationsthe bi-concave lens in the initial (left) and deformed (right) configurationsgeometry into the final glass oneFigure 5: Normal distance (in mm) between the desired and deformed glass profiles in a direction normal to the desired profile for each of the control nodes and for the bi-concave lens designFigure 6: Normal distance (in mm) between the desired and deformed glass profiles in a direction normal to the desired profile for each of the control nodes and for the bi-concave lens designFigure 7: Lower lens profile at each optimization loop for the plano-concave design。
材料成型及控制工程专业英语阅读翻译
第5章塑料成型及模具5. 1. 1注塑模具5.1.1一般注塑成型技术的处理器的持续发展的要求越来越多。
注塑成型过程中最重要的问题无疑是正确的注射。
因为设计成型形状的影响不大，如有的建设最多样化的注塑部件的机器。
高效的生产主要取决于注塑模具。
模具的耐久性取决于他们的护理和治疗。
由于总是硬化和地面的运动部件和模具型腔，他们之间产生500000和100000000张。
为了便于建设，降低制造成本，注塑模具成为标准化.一些公司提供基本现成的方形或圆形，立即使用.只需插入标准或卸料板模具设计的基础，那么，必须安装到基础。
5.1.2个基本模具结构5.1.2.1工作原理注塑模具基本上由两个半形.模具的一半包含浇道衬套和热流道系统，喷射系统。
成型部分是设在分界线另一半的房子。
5.1.2.2单或者多腔模具要成立一个关于在注塑模具型腔的选择计算，需要准确掌握的材料，要处理的注塑机和模具。
蛀牙和相对整机成本decrease.The生产对于一个给定的成型零件所需的时间越来越多的模具成本增加，取决于壁厚，注射速度，回收率，冷却dolded材料所需的时间，冷却模具的能力和保压时间期限，如必要的附带倍，射血时间，延迟时间等。
因此，决定确定的腔数取决于：（1）尺寸（成型零件的数量，交货时间顺序）（2）形状的模具零件（尺寸质量要求）（3）注塑机（锁模力，塑化和注射容量）（4）模具成本有几个已知的程序计算腔的经济。
不幸的是，他们是如此不同，这是不可能的凝结。
作为一个例子：理论最大。
腔数是F2必须等于或比F1小。
F1是：注塑模具的注射模成型车间成型车间，造型车间注塑成型注射成形的研磨（地上，地下）磨削，磨光单型腔模具单型腔注射模的多腔腔达到词语和术语的最大数量模多型腔注射模的阻尼力夹紧力;合模力塑化（使）成为可塑;（使）可塑注射容量注射容量。
5.1.3三板式注射模具三板式注射模具是具有两个分型面的注射模具，这种模具带有浇口，也就是直浇道在模型中和塑件相分离。
材料成型及控制工程专业外文翻译--材料的选择
外文原文：1 Physical Properties of MaterialsIn the selection of materials for industrial applications, many engineers normally refer to their average macroscopic properties, as determined by engineering tests, and are seldom concerned with microscopic considerations. Others, because of their specialty or the nature of their positions, have to deal with microscopic properties.The average properties of material are those involving matter in bulk with its flaws, variations in composition, and variations in density that are caused by manufacturing fluctuations. Microscopic properties pertain to atoms, molecules, and their interactions. These aspects of material are studied for their direct applicability to industrial problems and also so that possible properties in the development of the new materials can be estimated.In order not to become confused by apparently contradictory concepts when dealing with the relationship between the microscopic aspects of matter and the average properties of materials, it is wise to consider the principles that account for the nature of matter at the different levels of our awareness. These levels are the commonplace, the extremely small, and the extremely large. The commonplace lever deals with the average properties already mentioned, and the principles involved are those set forth by classical physics. The realm of theextremely small is largely explained by means of quantum mechanics, whereas that of the extremely large is dealt with by relativity.Relativity is concerned with very large masses, such as planets or stars, and large velocities that may approach the velocity of light. It is also applicable to smaller masses, ranging down to subatomic particles, when they move at high velocities. Relativity has a definite place in the tool boxes of nuclear engineers and electrical engineers who deal with particle accelerators. For production engineers, relativity is of only academic interest and is mentioned here for the sake of completeness.2 Mechanical Properties of MaterialsOnce the important physical properties of a material have been established, mechanical properties such as yield strength and hardness must be considered. Mechanical properties are structure-sensitive in the sense that they depend upon the type of crystal structure and its bonding forces, and especially upon the nature and behavior of the imperfections that exits within the crystal itself or at the grain boundaries.An important characteristic that distinguishes metals from other material is their ductility and ability to be deformed plastically without loss in strength. In design, 5 to 15 percent elongation provides the capacity to withstand sudden dynamic overloads. In order to accommodate such loads without failure, materials need dynamictoughness, high moduli of elasticity, and the ability to dissipate energy by substantial plastic deformation prior to fracture.To predict the behavior of a material under load, engineers require reliable data on the mechanical properties of materials. Handbook data is available for the average properties of common alloys at 68℉. In design, the most frequently needed data are tensile yield strength, hardness, modulus of elasticity, and yield strengths at temperatures other than 68℉. Designers less frequently use resistance to creep, notch sensitivity, impact strength, and fatigue strength. Suppliers’catalogs frequently give more recent or complete data.Production-engineering data that is seldom found in handbooks include strength-to-weight ratios, cost per unit volume, and resistance to specific service environments.A brief review of the major mechanical properties and their significance to design is included to ensure that the reader is familiar with the important aspects of each test.3Selecting MaterialsAn ever-increasing variety of materials is available, each having its own characteristics, applications, advantages, and limitations. The following are the general types of materials used in manufacturing today: Irons and steels (carbon, alloy, stainless, and tool and die steels)Nonferrous metals and alloys (aluminum, magnesium, copper, nickel, titanium, superalloys, refractory metal, beryllium, zirconium, low-melting alloys, and precious metals)Plastics (thermoplastics, thermosets, and elastomers)Ceramics, glass ceramics, glasses, graphite and diamond.Composite materials (reinforced plastics, metal-matrix and ceramic-matrix composites, and honeycomb structures).1)Properties of materialsWhen selecting materials for products, we first consider their mechnical properties:strength, toughness, ductility, hardness, elasticity, fatigue, and creep. The strength-to-weight and stiffness-to-weight ratios of material are also important, particularly for aerospace and automotive applications. Aluminum, titanium, and reinforced plastics, for example, have higher ratios than steels and cast irons. The mechanical properties specified for a product and its components should of course be for the conditions under which the product is expected to function. We then consider the physical properties of density, specific heat, thermal expansion and conductivity, melting point, and electrical and magnetic properties.Chemical properties also play a significant role in hostile as well as normal environments.Oxidation corrosion, general degradation of properties, toxicity, andflammability of materials are among the important factors to be considered. In some commercial airline disasters, for example, many deaths have been caused by toxic fumes from burning nonmetallic materials in the aircraft cabin.Manufacturing properties of materials determine whether they can be cast formed, machined, welded, and heat treated with relative ease. The method used to process materials to the desired shapes can adversely affect the product’s final properties and service life.2)Availability and costAvailability and cost of raw and processed materials and manufactured components aremajor concerns in manufacturing. Competitively, the economic aspects of material selection are as important as the technological considerations of properties and characteristics of materials.If raw or processed material or manufactured components are not available in the desired quantities, shapes, and dimensions, substitutes and/or additional processing will be required, which can contribute significantly to product cost. For example, if we need a round bar of a certain diameter and it is not available in standard form, then we have to purchase a larger rod and reduce its diameter by some means, such as machining, drawing through a die, or grinding.Reliability of supply, as well as demand, affects cost. Mostcountries import numerous raw materials that are essential for production. Note the reliance of the United States on imported raw materials. The broad political implication of such reliance on other countries is self-evident.Different costs are involved in processing materials by different methods. Some methods require expensive machinery, others require extensive labor, and still others require personnel with special skills or a high level of education or specialized training.3)Appearance, service life, and disposalThe appearance of materials after they have been manufactured into products influences .their appeal to the consumer. Color, feel, and surface texture are characteristics that we all consider when making a decision about purchasing a product.Time and service-dependent phenomena such as wear, fatigue, creep, and dimensional stability are important. These phenomena can significantly affect a product’s performance and, if not controlled, can lead to total failure of the product.Similarly, compatibility of materials used in a product is important. Friction and wear, corrosion, and other phenomena can shorten a product’s life or cause it to fail. An example is galvanic action between mating parts made of dissimilar metals, which corrodes the parts.Recycling or proper disposal of materials at the end of their usefulservice lives has become increasingly important in an age conscious of maintaining a clean and healthy environment. None, for example, the use of biodegradable packaging materials or recyclable glass bottles and aluminum beverage cans. The proper disposal of toxic wastes and materials is also a crucial consideration.中文译文：1.材料的物理性能在选择工业用材料时，许多工程师通常都只考虑其平均的宏观性能，因为这些特性是由工程实验确定的，而很少考虑其微观特性。
材料成型及控制专业英语考点
一、词组（英译汉、汉译英）mechanical property 机械(力学)性能metallic bond 金属键critical part and element 关键零部件electrostatic attraction 静电吸引plastic deformation 塑性变形self-strengthening 自强化deoxidation脱氧stress concentrator 应力集中点corrosion resistance 耐腐蚀plain carbon steel 普通碳钢hot-rolled steel 热轧钢alloying element 合金元素harmful impurity 有害杂质low alloy steel 低合金钢stress relief 应力松驰austenitic 奥氏体ferritic 铁素体martensite马氏体dislocation 位错viscosity 粘性shrinkage 收缩slip system 滑移系thermosetting 热固性的thermoplastic 热塑性的heating rate 加热速度constitutional diagram 状态图inhomogeneous 不均匀的inherent 内在的，本质的free energy 自由能center of crystallization 结晶核心sorbite索氏体troostite屈氏体isothermal decomposition 等温分解annealing 退火work hardening 加工硬化thermomechanical treatment 形变热处理normalizing 正火critical strain 临界应变stress-strain curve 应力应变曲线hardening 淬火holding temperature 保温温度activation energy 激活能tempering 回火holding time 保温时间yield or flow stress 屈服或流动应力nucleation rate 成核率driving force 驱动力two phase region 两相区linear dependence 线性关系defect 缺陷superplastic formability 超塑性成形forging 锻件，锻造drop stamping 锤上模锻difficult-to-machine alloy 难切削合金vapor cushioning 蒸汽垫final forging 终锻closed impression die 闭式压锻模rotary bending 旋转模弯曲fine blanking 精密冲裁cutting punch 冲裁凸模shearing zone 剪切区burr 毛刺confined chamber 闭式模锻wire drawing 拔丝stretch forming 拉伸成形hydrostatic extrusion 静液挤压tensile strength 拉应力stretch draw forming 拉深成形cold rolled sheet 冷轧板strain hardening 应变强化teach and playback 示教和重现explosive forming 爆炸成形strain gradient 应变梯度ejection 脱模，出坯，挤出magnetic forming 磁力成形injection mold 注射模compression mold 压模，压铸模plastics-processing 塑性加工multicavity mold 多型腔注射模milling 研磨，铣削grinding 磨削，研磨three-plate mold 三板式注射模polishing 磨光，抛光二、句子翻译1．Among numerous properties possessed by materials, their mechanical properties, in the majority of cases, are the most essential and there fore, they will be given much consideration in the book.在一些主要的应用场合，力学性能是材料的各种性能中最重要的性能，因此本书中将重点讨论。
材料成型外文文献翻译
WELDING FOR THE RAILROAD INDUSTRYBy Brian MeadeManager of Railroad Technical ServicesThe Lincoln Electric CompanyCleveland, Ohio. To meet their demanding service conditions, railroads continue to advance welding technology.There are several distinct differences between railroad welding and that of other industries. The bulk of all railroad welding is performed by either the engineering (track) department or the mechanical (car) department. Welding in the car and locomotive department generally uses the common arc welding processes to join materials such as mild steel, stainless, cast iron, and some manganese. The track department, however, is far more unusual and uses fewer, more specialized types of welding.The most common track welding functions are electric arc, thermite,, and flash butt. Standard arc welding processes such as SMAW, GMAW, and FCAW are used to weld manganese and carbon steel track components. However, thermite and flash butt are used for joining continuous welded rail. The flash butt method is used in the plant to create quarter-mile ribbon rails, which are then transported by a rail train to the location where they will be installed. Both flash butt and thermite (sometimes known as aluminothermic) are then used in the field, to join the larger lengths of rail together into continuous welded rail. They are also used in maintenance welding for replacing defective rail and for light construction.Following are some of the considerations that separate railroad welding from other fields. Most of the differences occur in the welding of rails and other track components, such as frogs(the parts of switches where the two tracks join) and crossing diamonds. Therefore, this article will focus most heavily on this area.Classes of Rail WeldingWelding is a process that joins rail ends by melting them with superheatedThermiteliquid metal from a chemical reaction between finely divided aluminum and iron oxide. (Fig.A5—from AWS D15.2). Filler metal is obtained from a combination of the liquid metal produced by the reaction and pre-alloyed shot in the mixture.Flash Butt Welding is a resistance welding process that produces a weld at the closely-fit surfaces of a butt joint, by a flashing action followed by the application of pressure after heating is substantially completed. Very high current densities at small contact points between the rail ends causes the flashing action, which forcibly expels the material from the joint as the rail ends are moved together slowly. A rapid upsetting of the two workpieces completes the weld.Welding refers to the standard arc welding processes used elsewhere, particularly Electricshielded metal arc welding (SMAW) or “stick welding (Fig. A1-- from AWS D15.2);gas metal arc welding (GMAW) (Fig. A2 --from AWS D15.2); and flux-cored arc welding (FCAW), with or without additional gas shielding (Fig. A3-- from AWS D15.2.) These processes are used on frogs and crossing diamonds (both manganese and carbon steel); for carbon steel rail ends, switch points, and wheel burns; and for joining carbon steel rails.Rail Service and Chemical CompositionPart of what makes rail welding different from other welding is the composition of the rail.Carbon content limits are 0.72% to 0.82%, while manganese can range between 0.80% and1.10%. Rail is subjected to continually varying loads, forces and stresses, in all kinds of temperatures and environments, and must carry out its task without failure for many years. Service demands on modern rail continue to become more severe, with loaded freight cars approaching 286,000 pounds. Wheel loads may reach 36,000 pounds, applied to a contact patch approximately the size of a dime. The resulting contact and shear stresses are severe, both in and on the railhead.While the first cast iron rail was produced in England in 1776, modern steel rail incorporates steelmaking techniques such as vacuum degassing and multiple-station argon gas stirring. Continuously cast, fully pearlitic, in-line head hardened rail is now being produced with head hardness values exceeding 380 Brinell.The result of these improvements is rail with better static and dynamic properties, in addition to more metallurgical cleanliness. The chemical composition limits for standard steel rail are shown in the AREA (American Railway Engineering Association) Manual for Railway Engineering (Table 2-1, Chapter 4, AREA Manual).Related mechanical properties are also spelled out in the AREA manual (Table 2-2, Chapter 4). These include a surface hardness of at least 300 Brinell for standard rail and between 341 and 388 Brinell for high-strength rail (alloy and heat-treated). The 388 Brinell upper limit may be exceeded, providing a fully pearlitic microsructure is maintained. Tensile properties required include a minimum yield strength of 70 ksi for standard rail and 110 ksi for high-strength rail; tensile strength minimums of 140 ksi and 170 ksi respectively; and minimum elongation in 2 inches of 9 percent for standard and 10 percent for high-strength.Thermite WeldingAlthough widely used in the railroad industry, thermite welding is probably one of the least understood processes in the balance of industry. Developed as an improvement to the earlier practice of bolting rail joints together, thermite welding still produces some closures with impact and fatigue properties that may be less than desirable. A 1996 Conrail1 study showed that, in 1994, 26.5 percent of total rail defects were attributable to weld failures, 18.3 percent were due to defective thermite welds and 8.2 percent were due to defective flash butt welds. However, the portability, cost-effectiveness, and convenience of thermite welding results in its continued extensive use.Thermite welds are actually as much a casting as they are a weld, and consistency may be difficult to achieve. Weld charge manufacturers have made significant improvements to thermite weld quality and hardness in recent years. Comparisons of welds made using thermite charges from two suppliers showed that the premium charges of one firm were typically harder and stronger than the standard charges produced by the other, although there was a substantially greater spread in the strength values obtained with the first firm’s welds. Thermite weld charge manufacturers can provide a variety of weld hardnesses, depending on customer needs. Higher hardness is deemed to be better, considering the desire of the railroads to have the rail last longer under increasingly severe axle loadings and tonnages. The higher hardness also improves fatigue and deformation resistance and more closely matches the hardness of new head-hardened rail,1An Investigation of Thermite Rail Weld Composition and Properties; Lonsdale. C.P., and Luke, S.T., Conrail Technical Services Laboratory, Altoona, PA; Proceedings of the 1996 International Conference on Advances in Welding Technology, Columbus, Ohio, pp. 447-460.which approaches 400 Brinell. Harder welds also stand up better to heavy traffic and help prevent localized railhead depressions and deformation at the weld.Aluminum plays a key role in thermite welding, where it not only reacts with iron oxide to provide the original heat for welding but also serves as a deoxidizer in the weld charge. Here, it tends to react with oxygen in the still-liquid casting as it solidifies, reducing weld porosity and increasing tensile strength. However, too much aluminum will embrittle the steel. To ensure weld quality and consistency, it is important to control all weld charge alloying elements and residuals to keep them within specificationsMany variables can affect the properties of welds produced by thermite field welding. Among them are welding procedures, including the amount of gap, preheat, rail movement, rail end cleanliness, weather during welding, crucible cleanliness, and welder skill.Flash Butt WeldingBecause aluminothermic rail weld failure rates tend to increase with higher axle loads, railroads are looking for viable alternative rail welds. In-track flash butt rail welding has gained great acceptance as an alternative. The process has proven to make strong, reliable welds in field conditions. However, because rail steel is consumed during the course of the process, in-track flash butt welding cannot presently be used as an alternative for all in-track applications.The flash butt welding process originally was developed in the former Soviet Union. However, it was improved and perfected in the U.S. by the Holland Company, a major flash butt welding contractor and builder of flash butt welding equipment. Large fixed plant flash butt rail welding plants are commonly used on major railroads units, but mobile truck-mounted units (Fig.6) can also take the equipment directly to the weld site. A typical unit aligns the rail ends, charges them electrically, and hydraulically forges the ends, melting the two ends together. Thewelderhead automatically shears upset metal to within 1/8" of rail profile. A base grinder then removes the 1/8" flashing material, leaving a smooth base and reducing the likelihood of stress risers that could shorten the life of the rail. A magnetic particle inspection, in addition to visual inspections, verifies the quality of the final weld.The flash butt welding process tends to produce a weld with a heat-affected zone that is much narrower than that of a typical thermite weld (Fig.7). This also results in a more consistent Brinell hardness profile across the finished weld, which signifies a lack of hard or soft spots that can cause welds to deform and ultimately fail.Electric Arc Welding of Frogs and Crossing DiamondsThe extra stresses incurred by frogs and crossing diamonds require a material with high strength and durability, and one that will resist failure under impact and heavy loading. To achieve these properties, they are typically cast from austenitic manganese steel, an extremely tough, nonmagnetic alloy with unique properties that differ from common structural and wear-resistant steels. One of these properties is its capacity for work hardening at the surface under impact while the underlying body retains its original toughness. Metal-to metal wear resistance is excellent, which is essential in rail applications.For trackwork castings, AREA requires conformance with ASTM A128, Standard Specification for Steel Castings, Austenitic Manganese, except for slightly modified chemical requirements that include:Carbon 1.00/1.30%Manganese 12.00% minimummaximumSilicon1.00%Phosphorus 0.07% maximumThe high manganese content stabilizes the austenite by retarding its transformation to other structures. Silicon acts mainly as a deoxidizer, while phosphorus is limited because it tends to promote hot cracking, during casting as well as in subsequent welding operations.Other than these special limits, the metallurgy of cast rail components is similar to other austenitic manganese castings. Understanding the basic metallurgy of this material will make it easier to relate to the special aspects of welding it. At high temperatures, the structure of all types of steel is essentially austenitic. Although most carbon and alloy steels transform to other structures as they cool, the addition of large amounts of manganese combined with sufficiently fast cooling suppresses this transformation. Manganese steel castings may be relatively brittle before heat treatment, as normal cooling rates in the mold are too slow to retain a fully austenitic structure. This is rectified by heating and holding at the appropriate austenitizing temperature (generally 1850 to 1950 F), then quenching in cold, agitated water. Proper procedures are important, since either inadequate austenitizing or too slow cooling can result in excessive carbides that will lower the mechanical properties.Reheating of manganese steels can also cause carbide precipitation and resulting embrittlement, with the degree depending upon both exposure time and temperature. Thus, it is necessary to use welding procedures that will minimize or avoid prolonged overheating.This and other considerations make electric arc welding of manganese frogs an area that can sometimes confuse a newcomer to this field. Without the ability to properly focus on all data generated by the manufacturer of welding materials, the weldor can easily be perplexed by the erratic results achieved with different welded track castings. The difficulty can arise from a number of areas.Lincoln Electric conducted a study of manganese frog welding failures in October, 1996.A team of engineers, assembled to evaluate weld metal fatigue in a #10 rail bound manganese casting, studied these areas:Number of times weldedGross MGT (million gross tons/year) on track segmentAge and type of castingsWelding procedureWelding materials compositionComposition of the base castingThere have been claims of premature cracking in weld deposits made with manual electrode and wire on frog castings for nearly 60 years. Lincoln Electric has recorded data from 1937 that supports the usage of a manganese-based formulation in a product developed to rebuild manganese frog castings. At that time, Lincoln supplied a 12-14% manganese electrode to the railroads along with a stainless electrode to seal cracks that were in the original castings. The stainless steel electrode was used only in the flangeways and deep in the bottom of the casting, prior to buildup with the manganese-based electrode. The 1996 study supported the earlier data and also yielded some interesting conclusions for improvements in the technique used.The as-received casting is shown in Fig. 1. A closeup view of the cracking area is shown in Fig. 2. Sections AA and BB were made with a carbon arc torch to remove the cracked portion for further study.Sections CC and EE in Fig. 3a were made to study the region near the point that seemed to be free of cracks on the surface. Cracks were observed in the base metal and in the weld. The morphology of the cracks indicates that the preexisting cracks in the base metal have grown intothe weld during or at the end of welding, and these have subsequently opened up under load in service (Fig. 3b and 3c). In addition, the presence of a repair weld near the base metal can be seen in Fig. 3b. This was identified as a 312 stainless weld, which was put down to repair cracks in the base casting prior to building up with a manganese electrode.The cracks in the base casting follow the austenite grain boundaries, as shown in the higher magnification view, Fig. 3d. As they grow into the weld, they continue along the austenite grain boundaries as seen in Fig. 3e. A full section of the weld with the whole casting (Section EE) is shown in Fig. 4a. As is evident, there are cracks in the base metal that subsequently run into the weld metal (Fig. 4b). Based on this evidence, this cracking phenomenon appears to be a form of hot cracking.Sections FF, GG, and HH were taken in the cracked region (Fig. 5a). Section GG is shown in Fig. 5b and indicates that the cracks at the top have opened up under the loading during service.Conclusions for Improving Weld Repair PerformanceIn summary, the welding in this example was done in a situation that caused hot cracking. Chemical analysis reveals that the phosphorus level in the base casting is somewhat on the high side. The effect of phosphorus in causing hot cracking is well known (See AWS D15.2 Annex B for discussion of phosphorus under B2 and B6.2).The evidence of the stainless bead (used to seal a crack prior to buildup with manganese electrode) shows that the cracks in the base casting grew along the austenite boundary until they reached the stainless deposit. This deposit retarded the growth of the cracks and protected the weld deposit. Changing the technique to include a light layer of 308L or 312 stainless steel canonly improve the performance of the weld repair. Lower heat input while welding can help reduce hot cracking. Wirefeed welding processes that favor lower heat input are highly recommended, as opposed to “stick” welding. Lincoln Electric continues to conduct experiments to determine whether manganese electrode deposit chemistry can be further optimized to provide greater resistance to weld cracking growing from preexisting cracks in the base casting.# # #15-195CP/11-17-97。
材料成型及控制工程外文翻译--金属热处理
外文原文：Metal heat treatmentMetal heat treatment is a kind of craft to heat pieces of metals at the suitable temperature in some medium and to cool them at different speed after some time.The metal heat treatment is one of the important crafts in the machine-building, comparing with other technologies, the heat treatment seldom changes the form of the work pieces and chemical composition of the whole .it improve the serviceability of the work piece through changing their micro- work pieces, chemical composition, or surface. Its characteristic is improving inherent quality of work pieces which can not be watched by our eyes.In order to make the metal work piece have mechanics , physics and chemical property which are needed, besides the use of many materials and various kinds of crafts which are shaped , the heat treatment craft is essential. Steel is a wide-used material in the mechanical industry, its complicated micro-composition can be controlled through the heat treatment , so the heat treatment of the steel is a main content of the metal heat treatment . In addition aluminium, copper, magnesium, titanium and their alloys also can change their mechanics , physics and chemical property through the heat treatment to make different serviceability.During the process of development from the Stone Age to the Bronze Age and to the Iron Age, the function of the heat treatment is gradually known by people. As early as 770 B.C.~222 B.C., the Chinese in production practices had already found the performance of the copper and iron changed by press and temperature . White mouthfuls of casting iron’s gentle-treatment is a important craft to make farm implements.In the sixth century B.C., the steel weapon was gradually adopted. In order to improve the hardness of the steel, quench craft was then developed rapidly. Two sword and one halberd found in YANXIA, Hebei of China , had “MA structure” in its micro-composition which was quenched.With the development of quenching technology, people gradually found the influence of cold pharmaceutical on quality of quenching. Pu yuan a people of theThree Kingdoms(now, Shanxi province Xiegu town)made3000 knives for Zhu Ge-liang.the knives were quenched in Chengdu according to legend. This proved that the chinese had noticed the cooling ability of waters with different quality in ancient times, and the cooling ability of the oil and urine at the same time were found. People found a sword in Zhongshan tomb which were up to the Western Han Dynasty (B.C. 206 -A.D. 24 ),in whose heart department carbon was about 0.15-0.4%, but on whose surface carbon was about more than 0.6%.this has shown the use of the carburization craft. But as the secret of individual's " craftsmanship " at that time, the development was very slow.In 1863, Britain metallo graphy expert and geologist's discoverity that six kinds of different metallography organizations existed in the steel under the microscope, proved that the inside of steel would change while heating and cooling. the looks of steel at the high temperature would change into a harder looks when urgently colded. Frenchmen Osmon established Allotropic theory , and Englishmen Austin first made the iron- carbon looks picture .these tow theories set the theoretical foundation for the modern heat treatment craft . Meanwhile, people also studied the metal protection in the heating to avoid the metal's oxidizing and out of carbon in the course.1850~1880s, there were a series of patent to use kinds of gases to heat (such as hydrogen , coal gas , carbon monoxide etc. ). Englishman's Rec obtained the patent of bright heat treatment of many kinds of metal in 1889-1890.Since the 20th century, the development of metal physics and transplantation application of other new technologies,make the metal heat treatment craft develop on a large scale even more. A remarkable progress was carburizition of gas in a tube of stoves in industrial production during 1901~1925; 1930s the appeariance of the electric potential different count and then the use of carbon dioxide and oxygen made stove carbon of atmosphere under control . In 1960s, hot treatment technology used the function of the plasma field, developed the nitrogen, carburization craft.The application of laser , electron beam technology, made the metal obtain new method about surface heat treatment and chemical heat treatment.The metal heat treatment craftThe heat treatment craft generally includes heating, keeping and cooling andsometimes only heating and cooling two progresses . The course links up each other.Heating is one of the important processes of the heat treatment . There are a lot of heating methods of the metal heat treatment . the first heat source were the charcoal and coal , then liquid and gaseous fuel. The application of the electricity is easy to control the heating, and no environmental pollution. the heat source could be heated directly or indirectly by the use of salt or metal of melting or the floating particle.While metal heated, the work piece in air , is often oxidized or take off carbon ( steel's surface carbon content reduces).this does harm to the metal's surface performanc which is heated. Therefore metal should heat in the the vacuum or the melted salt, in controlled atmosphere or protected atmosphere . Sometimes it is heated in the protect means of coating or pack .Heating temperature is one of the important craft parameters of the heat treatment craft , choosing and controling heating temperature is a main matter of guaranting heat treatment quality. Heating temperature may change according to the different purposes of the heat treatment and different metal materials , but usually it is up to the temperature at which high temperature frame could be abtained.it must keep some time at the high temperature to make the inside and outside of the metal reach the some heating level,so that its micro-frame would turn out wholely.we call this period of time "keep-heat"time. There is no "keep-heat"time when adopting density heating and surface heat treatment of high energy because of the rapidity. But the chemical heat treatment often need much more time to sustain the heat .Cooling is an indispensable step in the craft course of heat treatment too . cooling methods are different because of crafts , mainly at controling the speed of cooling. generally anneals is slowest in speed, the cooling normalizing is a little fast in speed, the quenched cooling is much faster in speed. But there are different demands according to the kindof steel, for example empty hard steel can be cooled with normalize as quick as the speed by hard quench .The metal heat treatment craft can be divided into whole heat treatment , surface heat treatment and chemical heat treatment.Every kind could be divided into different crafts according to heating medium , heating temperature and cooling method. The same kind of metal adopting different heat treatment crafts can getdifferent organizations which have different performance . The steel is the widest-used metal on the industry, and its micro- organization is the most complicated, so the steel heat treatment craft is various in style.The whole heat treatment is to change the whole mechanics performance of work piece through heating the work piece wholely and then cooling at the proper speed. The whole heat treatment of steel roughly has four basic crafts of annealing , normalizing , quenching and flashing back .Annealing means heating the work piece to the proper temperature ,then adopting different temperature retention time according to the material and size of work piece and then cooling slowly, whose purpose is to make the metal organization to achieve or close to the balance state, obtain good craft performance and serviceability, or prepare for quench further. normalizing is to cool in the air after heating the work piece at suitable temperature , its result is similar to annealing except that the organization out of normalizing are more refined which is often used to inhance the cutting performance of the material and is occationally used for the final heat treatment of material which are not high-requested. .Quenching is to cool work piece which has been heated and kept in warm fast in the cold medium as water , oil , other inorganic salts ,or organic aqueous solution and so on . The steel quenched becomes hard and fragile too. To reduce its fragility , we must first keep the quenched piece of steel in a certain temperature which is higher than room temperature but lower than 650℃for a long time,and then cool it again. this progress is called the flashing back . Annealing , normalizing, quenching , flashing back is " four fires " in the whole heat treatment . the quenching contact close to flashing back ,and they are often used together." Four fire "is divided into kinds of heat treatment crafts by different heating temperatures and diferent ways of cooling. What is " quality adjust " is a kind of craft combining "quench" with "high-temper a ture flash back" to make the work piece obtain certain intensity and toughness. Some alloy saturation out of quench can improve its hardness, intensity, electricity and magnetism after it is kept in the high proper temperature for a little long time . Such heat treatment craft is called “effective dealing”.Deformation-heat-treatment is the combination of pressure-deformation and heat treatment on work piece ,this mothod could enhance its intensity; and vacuum-heat-treatment is that work piece is heated in atmosphere or vacuum.It can make the work piece not oxidize or take off carbons , keep its surface bright and neat and improve its performance. At the same time ,it can carry on the chemical heat treatment by the pharmaceutics.Surface heat treatment on work piece is only to heat its cover to change the metal-layer's mechanics performance. In order to only heat the layer of work piece without making too much heat spreading into the inside, the heat source used must be of high density of energy , namely it can offer greater heat energy on the unit's area of the work piece and make its layer or parts reach high temperature in short-term or instantaneously. The main method of the surface heat treatment is "flame quenching" and "reaction heat" treatment and the heat source used commonly are flame as oxygen acetylene or propane, reaction electric current, laser and electron beam,ect.The chemical heat treatment is to alter the chemical composition, organization and performance of the top layer of work piece.The difference between Chemical and surface heat treatment is that the latter just change the chemical composition of the top layer of work piece . The former is to set the work piece heating in the medium (the gas , liquid , solid ) including carbon , nitrogen or other alloying elements,and then to keep it warm for longer time, thus to make elements as the carbon,nitrogen,boron and chromium,etc permeate through the top layer of work piece.Sometimes after permeation, there is other heat treatment craft to carry on such as quenching and flashing back . The main method of the chemical heat treatment include carbon,nitrogen, and metal permeation.The heat treatment is one of the important processes in machine components and tool and mould manufacture. Generally speaking, it guarantees and improves various kinds of performance of the work piece , for instance wear proof and anti-corrosion. It also improve the organization and state of the tough work piece to ensure various kinds of cooling and heating work.For example tin are annealed for a long time to turn into malleable cast iron which is of plasticity. proper heat treatment craft can prolong the gear wheel's servicelife at double or dozens of times than these without heat treatment ; In addition, the cheap carbon steel with some alloying elements permeated will own the alloy steel performance whose prices hold high so that it can replace some heat-resisting steel , stainless steel ; all tool and mould need to be through the heat treatment before in use..中文译文：金属热处理金属热处理是将金属工件放在一定的介质中加热到适宜的温度，并在此温度中保持一定时间后，又以不同速度冷却的一种工艺。
《材料成型及控制工程 专业英语阅读 》翻译
第一章材料及其性能1。
1金属和非金属许多属性具有材料之一，其机械性能，在大多数情况下，是最重要的，因此，他们将在本书太多的考虑。
所有关键部件和元件，其中一个高可靠性的要求，都是用金属制作的，而不是玻璃，塑料或石头。
已升了SEC，金属的特点是金属键；在正离子占据晶格的网站和周围的电子气。
所有非金属离子和共价键。
这些类型的债券是刚性的，是由于两个不同的电荷离子的静电引力。
由于金属键，金属塑性变形能力和自我强化的塑性变形。
因此，如果在一个物质或者元素的形状是这样，有应力集中的缺陷，在这些点上的应力可以达到一个巨大的价值，甚至导致开裂。
但是，由于材料的塑性越高，金属在塑性变形这一点，说，在裂纹尖端，经过强化，骨折的过程中，涉及到一个逮捕。
这不是在非金属发生。
他们是不可能的塑性变形和自我强化；因此，裂缝将尽快在缺损的尖端的应力超过一定值时发生。
这些事实说明为什么金属是可靠的结构材料和不可超越的非金属材料。
1。
2铁合金以上的人类使用的金属材料，重量90%铁合金。
这代表了范围广泛的组织工程材料的一个巨大的家庭及相关性质。
工程设计要求结构承重或电力传输大多数涉及铁合金。
作为一个实际问题，这些合金分为基于碳在合金成分两大类。
钢通常包含在0。
05和2重量%的碳。
铸铁通常含有2和4.5重量%的碳之间。
在钢的范畴，我们应当区分是否显着量的合金元素碳以外的使用。
的组合物的5重量%的总的非碳的加入将作为低合金高合金钢之间的边界。
这些合金元素都经过精心挑选，因为他们总是带来大幅增加材料成本。
只有在性能如强度高、耐蚀性能提高的改进证明他们是必不可少的。
2。
钢的热处理的1原则热处理在现代机械工程的作用不能被高估。
在因热处理金属性能的变化是极为重要的意义。
2。
1。
1温度和时间目的的任何热处理工艺是通过加热到指定的温度和随后的冷却产生在金属结构所需的变化。
因此，在热处理的主要因素是温度和时间，所以，任何热处理过程可以在温度时间（Tτ）坐标表示热处理条件的特点是通过以下参数：加热温度T最大，即为合金金属加热的最高温度；在加热温度τH保温时间；加热速率νH和冷却速率如果加热（或冷却）是在一个恒定的速率，温度时间关系会以各自的角度倾斜的直线描述。
材料成型及控制工程外文文献翻译--AZ31镁合金在高温下的吹塑成型
毕业设计（论文）的外文文献翻译原始资料的题目/来源： Blow forming of AZ31 magnesiumalloys at elevated temperatures/ORIGINAL RESEARCH 翻译后的中文题目： AZ31镁合金在高温下的吹塑成型院（系）材料科学与工程学院专业材料成型及控制工程中文翻译AZ31镁合金在高温下的吹塑成型1.摘要：本文研究和报道了关于AZ31B镁合金商业片在高温下的成形行为。
实验分两个阶段进行。
第一阶段是分析自由胀形实验，第二阶段是分析板材填充封闭模具的能力。
施加不同的压力和温度，用标本圆拱高度表征参数，在相同时实验中，使用分析的方法来计算应变速率敏感指数。
因此适当的成形参数如温度和压力，对于随后的成形实验是有用处的。
第二阶段中，在带有棱形空腔的密闭模具中进行成形实验。
同时分析了相关的过程参数对成形结果中壁厚填充、最终样品上圆角半径及分布的影响。
闭模成形实验证明：如果工艺参数选择适当，所研究的商业镁板可成形复杂的几何形状。
2.关键词：吹塑成形、材料特性、AZ31镁合金3.简介在众多结构材料中，镁合金以其低比重得到了行业厂家越来越多个兴趣，镁合金在具有最低的密度，在轻量化上也有很高的潜力，尤其是在移动正在使用运动部件的领域。
在这些应用中，越来越多地为轻质合金材料，尤其是传统的成形方法无法快速有效的成形镁合金等合金，使得超塑性成形（SPF）成为一种有吸引力的成形方法。
事实上，具有极其复杂形状的轻量化部件可以由具有超塑性的单层板通过超塑性成形制造。
轻金属合金如铝、钛和镁，有些难以在传统的成形条件下成形，吹塑成形（BF）的应用随之越来越多。
吹塑过程主要是将坯料放入模具型腔中，并在其上施加成形气体（如空气、氩气）。
相比基于成形操作的流体，在高温成形的区域，气体的耐热性为实现更高的温度提供了可能[1]。
该气体可完全替代传统冲压工序中的驱动冲头，并且允许具有高细节层次的不同种类材料的变形。
《材料成型及控制工程专业英语阅读》翻译系列11.1
《材料成型及控制工程专业英语阅读》翻译CHAPTER 11 CASTING铸造工艺的主要分类依据是其所应用的铸造种类。
这些铸型是型砂、塑料粘结壳型、永久型和半永久型金属型。
压铸用金属型、石膏型、熔模铸造铸型。
11.1 各种铸造工艺砂型的第一步是制作一个金属的或木质的模样，模样就是将要制成的铸件的复制品，但尺寸要比铸件的稍大一些。
模样通常是由两个或多个部分组成，从而能容易地从铸型中被取出来。
为了制作铸型，型砂被压实并填充在模样的四周，而型砂是放在一个像箱子似的容器也就是沙箱里的。
沙箱内充满砂型之后，撤出模样，就留下可一个与成品铸件形状相似的型腔。
如果铸件上有中空的部位，例如：车轮里的一个轴心孔，那么型腔里的孔洞形状的地方必须填上型砂。
这些制空的形状就是所谓的型芯。
用于铸件和型芯的型砂是由粘土和颗粒粘结剂混合成的。
如果砂型经过了烘干，那么就称之为干砂型：如果是在潮湿的状态下使用，则成为湿型砂。
干砂型比湿砂型具有更大的强度，更大的抗腐蚀能力和抗碎性。
填充型砂之前，在模样的表面覆上一层细的沙也就是所谓的面纱。
这样可以提高砂型铸件的表面质量。
塑性粘结壳型铸件是砂铸的一种改进形式。
一个金属模样加热到350℉左右（175℃），然后夹放到一个充满细砂和热固树脂的箱子上面。
当箱子倒过来，它里面的物质就掉落在热模样上，那么树脂受热就会软化。
这样，就在模样的周围形成以薄壳层的铸件材料。
然后箱子转回到其初始的位置，未反应的树脂和砂型就从模样上掉下来。
当树脂有足够的时间充分（完全）固化之后，这么壳层就剥落下来。
最终的铸型由两片相配的壳层组成，壳层紧紧地靠在一起，且四周是由沙箱中的金属颗粒支撑物所包围，而使用这种颗粒物提高了冷却和凝固速度。
永久型和半永久型的铸件是由金属制成的。
如果需要永久型铸型甚至使用金属型芯。
半永久型使用砂型芯。
铸型的两部分通常紧紧地铰接在一起，并使用螺钉装置紧固。
铸型图层或涂料由耐火材料，像石墨或三氧化二铁这样的润滑剂和粘结剂组成，其有助于铸件从铸型中取出。
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中英文对照外文翻译文献(文档含英文原文和中文翻译)一个描述电铸镍壳在注塑模具的应用的技术研究摘要：在过去几年中快速成型技术及快速模具已被广泛开发利用. 在本文中,使用电芯作为核心程序对塑料注射模具分析. 通过差分系统快速成型制造外壳模型. 主要目的是分析电铸镍壳力学特征、研究相关金相组织,硬度,内部压力等不同方面，由这些特征参数以生产电铸设备的外壳. 最后一个核心是检验注塑模具.关键词：电镀；电铸；微观结构；镍1. 引言现代工业遇到很大的挑战，其中最重要的是怎么样提供更好的产品给消费者,更多种类和更新换代问题. 因此,现代工业必定产生更多的竞争性. 毫无疑问,结合时间变量和质量变量并不容易,因为他们经常彼此互为条件; 先进的生产系统将允许该组合以更加有效可行的方式进行，例如,如果是观测注塑系统的转变、我们得出的结论是,事实上一个新产品在市场上具有较好的质量它需要越来越少的时间快速模具制造技术是在这一领域, 中可以改善设计和制造注入部分的技术进步. 快速模具制造技术基本上是一个中小型系列的收集程序，在很短的时间内在可接受的精度水平基础上让我们获得模具的塑料部件。
其应用不仅在更加广阔而且生产也不断增多。
本文包括了很广泛的研究路线,在这些研究路线中我们可以尝试去学习，定义，分析，测试，提出在工业水平方面的可行性，从核心的注塑模具制造获取电铸镍壳，同时作为一个初始模型的原型在一个FDM设备上的快速成型。
不得不说的是,先进的电铸技术应用在无数的行业，但这一研究工作调查到什么程度,并根据这些参数,使用这种技术生产快速模具在技术上是可行的. 都产生一个准确的，系统化使用的方法以及建议的工作方法.2 制造过程的注塑模具薄镍外壳的核心是电铸,获得一个充满epoxic金属树脂的一体化的核心板块模具(图1)允许直接制造注射型多用标本，因为它们确定了新英格兰大学英文国际表卓华组织3167标准。
这样做的目的是确定力学性能的材料收集代表行业。
该阶段取得的核心[4]，根据这一方法研究了这项工作,有如下:a,用CAD系统设计的理想对象b模型制造的快速成型设备(频分多路系统). 所用材料将是一个ABS塑料c一个制造的电铸镍壳，已事先涂有导电涂料(必须有导电).d无外壳模型e核心的生产是背面外壳环氧树脂的抗高温与具有制冷的铜管管道.有两个腔的注塑模具、其中一个是电核心和其他直接加工的移动版. 因此,在同一工艺条件下，同时注入两个标准技术制造，获得相同的工作。
3 获得电壳:设备电镀是电解质时电流的化学变化,电解所形成的直流电有两个电极，阳极和阴极。
当电流流经电路，在离子溶液中转化为原子。
电镀液用于这项工作是由氨基磺酸镍400 毫升/升,氯化镍(10克/升)、硼酸(50克/升),allbrite SLA(30毫升/升),allbrite703(2毫升/升). 选择这种组合主要原因是我们考虑注塑模具程序是玻璃纤维. 氨基磺酸镍让我们获得可以接受的内部压力(测试不同工艺条件结果,而不是最佳工艺条件约2兆帕最高为50兆帕). 不过,这种内部压力是由touenesulfonamode 衍生物和甲醛水溶液使用的ALLbrite添加剂的结果。
这种添加剂也增加了壳的阻力. Allbrite703是一种可生物降解水溶液表使用剂氯化镍,有利于解决金属统一分布在阴极，提高导电性的问题。
硼酸作为PH值缓冲区。
该设备用于制造壳的测试如下：●聚丙烯:600毫米×400毫米×500毫米的尺寸●三聚四氟乙烯电阻器,每一个有800W●具有机械搅拌系统的阴极●循环和过滤系统用的泵和聚丙烯过滤器。
●充电整流器. 最大强度在连续50个A和连续电流电压介于0至16伏●篮钛镍阳极(镍硫回合电解镍)纯度99%以上●气体注入系统一旦电流密度( 1-22A/dm）,温度(35至55℃)和pH值,已经确定，执行参数以及测试的进程部分不可改变。
4 获得硬度电壳硬度的测试一直保持在相当高的很稳定的结果。
如图2，可以看到：电流密度值2.5到22A/dm，硬度值介于540到580高压，PH值为4+-0.2和温度为45摄氏度，如果PH减少到3.5和温度为55摄氏度，硬度为520以上，高压低于560.这一测试使常规组成不同于其他氨基磺酸镍，允许其经营更加广泛，然而，这种operatyivity将是一定的取决于其他因素，如内部压力，因为他可能的变异。
改变PH值，电流密度和温度等，另一方面，传统的硬度氨基磺酸镍承受的高压在200-250之间，远低于取得的一个实验结果的电压。
对于一个注塑模具，硬度可以接受的起点300高压这是必须考虑的，注塑模具中最常见的材料，有改善钢（290高压），整体淬火（520-595高压），casehardened钢铁（760-8--高压）等，以这样一种方式，可以看到，注塑模具硬度水平的镍是壳内的高范围的材料。
因为这是一个负责内部压力的塑料注射液，这种方式与环氧树脂灌浆将遵循它，相反对低韧性的壳补偿，这就是为什么它是必定尽可能的外壳厚度均匀，并没有重要的原因，如腐蚀。
5 金相组织为了分析金相结构、电流密度、温度主要变化. 在正面横向部分（垂直沉积）对样品进行了分析，为了方便地封装在树脂，抛光。
铭刻，在不同阶段的混合乙酸和硝酸。
该时刻间隔15,25,40,50之后再次抛光, 为了在金相显微镜下观察奥林巴斯PME3-ADL3.3X/10X 必须要说的是，这一条规定显示了图片之后的评论，用于制造该模型的壳在FDM快速成型机里融化的塑料材料（澳大利亚统计局）巩固和解决了该阶层。
后来在每一个层，挤出的模具都留下一个大约0.15毫米直径横向和纵向的线程。
因此，在表面可以看到细线表面头部的机器。
这些西路将作为参考信息解决镍的重复性问题。
重复性的模型将作为一个基本要素来评估注塑模具的表面纹理。
表1测试系列：表1. 检验系列系列pH 温度(℃)电流密度A/mm21 4.2 ±0.2 55 2.222 3.9 ±0.2 45 5.563 4.0 ±0.2 45 10.004 4.0 ±0.2 45 22.22图3说明该系列第一时刻表面的样本它显示了流道起点的频率复用机，这就是说，又一个很好的重复性。
它不能仍然要注意四舍五入结构。
在图4 系列2，经过第二次，可以看到一条线的流道的方式与以前的相比不太清楚。
在图5系列3虽然第二次时刻开始出现圆形晶结果是非常困难的。
此外，最黑暗的部分表明时刻不足的进程和组成。
这种现象表明，在低电流密度和高温条件下工作，得到更小的晶粒尺寸和壳重现性好，就是所需要的足够的应用程序。
如果分析横向平面进行的沉积，可以在所有测试样品和条件增长的结构层（图6），牺牲一个低延展性取得令人满意的高机械阻力，最重要的是添加剂的使用情况，氨基磺酸镍液的添加剂通常创建一个纤维和非层状结果[9].这个问题表明在任何情况下改变润湿剂，由于该层结构的决定因素是这种结构的应力减速器（ALLbriteSLA)。
另一方面，她也是测试的层状结构不同厚度中的电流密度.6 内部压力壳的一个主要特点是应该有其应用，如插入时要有一个低水平的内部压力。
测试不同的温度很电流密度，所采取的措施取决于阴极弯曲张力计法。
A钢测试控制使用侧固定和其他自由度固定（160毫米长，12.7毫米宽，0.3毫米厚）。
金属沉积只有在控制了机械拉伸力（拉深或压应力），才能计算内部压力。
弹性的角度来看，斯托尼模型应用，假定镍基质厚度，对部分钢材产生足够小（3微米）的影响。
在所有测试情况下，一个能够接受的应用程序在内部压力在50兆帕的极端条件下和2兆帕的最佳条件下产生。
得出的结论是，内部压力在不同的工作条件和参数没有明显的变化条件下。
7 校验注塑模具试验已进行了各种代表性热塑性材料如聚丙烯、高密度聚乙烯和PC、并进行了注射部件性能的分析，如尺寸，重量，阻力，刚度和柔性。
对壳的力学性能进行了拉伸破坏性测试和分析。
大约500个注射液在其余的条件下，进行了更多的检验总体而言, 为分析一种材料，重要的是注意到行为标本中的核心和那些加工腔之间的差异。
然而在分析光弹注入标本（图7）有人注意到不同的国家之间张力存在两种不同的类型的标本，是由于不同的模腔热传递和刚度。
这种差异解释了柔性的变化更加突出的部分晶体材料，如聚乙烯和聚酰胺6.有人注意到一个较低的柔性标本在的高密度聚乙烯分析测试管在镍核心的情况下，量化30%左右。
如尼龙6这个值也接近50%。
8 结论经过连续的测试，注塑模具在不同条件下检查的氨基磺酸镍液使用添加剂。
这就是说塑性好，硬度好和摩擦力好的层状结构，已取得的力学性能是可以接受的。
借鞋缺陷的镍壳将部分取代环氧树脂为核心的注塑模具，使注入的一系列中型塑料零部件达到可接受的质量的水平。
参考资料[1] A.E.W. Rennie, C.E. Bocking and G.R. Bennet, Electroforming of rapid prototyping mandrels for electro discharge machining electrodes, J. Mater. Process. Technol.110(2001), pp. 186–196. [2] P.K.D.V. Yarlagadda, I.P. Ilyas and P. Chrstodoulou, Development of rapid tooling for sheet metal drawing using nickel electroforming and stereo lithography processes, J. Mater. Process. Technol.111 (2001), pp. 286–294.[3] J. Hart, A. Watson, Electroforming: A largely unrecognised but expanding vital industry, Interfinish 96, 14 World Congress, Birmingham, UK, 1996.[4] M. Monzón et al., Aplicación del electroconformado en la fabricación rápida de moldes de inyección, Revista de Plásticos Modernos.84(2002), p. 557.[5] L.F. Hamilton et al., Cálculos de Química Analítica, McGraw Hill (1989).[6] E. Julve, Electrodeposición de metales, 2000 (E.J.S.).[7] A. Watson, Nickel Sulphamate Solutions, Nickel Development Institute (1989).[8] A. Watson, Additions to Sulphamate Nickel Solutions, Nickel Development Institute (1989).[9] J. Dini, Electrodeposition Materials Science of Coating and Substrates, Noyes Publications (1993).[10] J.W. Judy, Magnetic microactuators with polysilicon flexures, Masters Report, Department of EECS, University of California, Berkeley, 1994. (cap′. 3).A technical note on the characterization of electroformed nickel shells for their application to injection molds——a Universidad de Las Palmas de Gran Canaria, Departamento de Ingenieria Mecanica, SpainAbstractThe techniques of rapid prototyping and rapid tooling have been widely developed during the last years. In this article, electroforming as a procedure to make cores for plastics injection molds is analysed. Shells are obtained from models manufactured through rapid prototyping using the FDM system. The main objective is to analyze the mechanical features of electroformed nickel shells, studying different aspects related to their metallographic structure, hardness, internal stresses and possible failures, by relating these features to the parameters of production of the shells with an electroforming equipment. Finally a core was tested in an injection mold.Keywords: Electroplating; Electroforming; Microstructure; Nickel 1. IntroductionOne of the most important challenges with which modern industry comes across is to offer the consumer better products with outstanding variety and time variability (new designs). For this reason, modern industry must be more and more competitive and it has to produce with acceptable costs. There is no doubt that combining the time variable and the quality variable is not easy because they frequently condition one another; the technological advances in the productive systems are going to permit that combination to be more efficient and feasible in a way that, for example, if it is observed the evolution of the systems and techniques of plastics injection, we arrive at the conclusion that, in fact, it takes less and less time to put a new product on the market and with higher levels of quality. The manufacturing technology of rapid tooling is, in this field, one of those technological advances that makes possible the improvements in the processes of designing and manufacturing injected parts. Rapidtooling techniques are basically composed of a collection of procedures that are going to allow us to obtain a mold of plastic parts, in small or medium series, in a short period of time and with acceptable accuracy levels. Their application is not only included in the field of making plastic injected pieces [1], [2] and [3], however, it is true that it is where they have developed more and where they find the highest output.This paper is included within a wider research line where it attempts to study, define, analyze, test and propose, at an industrial level, the possibility of creating cores for injection molds starting from obtaining electroformed nickel shells, taking as an initial model a prototype made in a FDM rapid prototyping equipment.It also would have to say beforehand that the electroforming technique is not something new because its applications in the industry are countless [3], but this research work has tried to investigate to what extent and under which parameters the use of this technique in the production of rapid molds is technically feasible. All made in an accurate and systematized way of use and proposing a working method.2. Manufacturing process of an injection moldThe core is formed by a thin nickel shell that is obtained through the electroforming process, and that is filled with an epoxic resin with metallic charge during the integration in the core plate [4] This mold (Fig. 1) permits the direct manufacturing by injection of a type a multiple use specimen, as they are defined by the UNE-EN ISO 3167 standard. The purpose of this specimen is to determine the mechanical properties of a collection of materials representative industry, injected in these tools and its coMParison with the properties obtained by conventional tools.Fig. 1. Manufactured injection mold with electroformed core.The stages to obtain a core [4], according to the methodology researched in this work, are the following:(a) Design in CAD system of the desired object.(b) Model manufacturing in a rapid prototyping equipment (FDM system). The material used will be an ABS plastic.(c) Manufacturing of a nickel electroformed shell starting from the previous model that has been coated with a conductive paint beforehand (it must have electrical conductivity).(d) Removal of the shell from the model.(e) Production of the core by filling the back of the shell with epoxy resin resistant to high temperatures and with the refrigerating ducts made with copper tubes.The injection mold had two cavities, one of them was the electroformed core and the other was directly machined in the moving platen. Thus, it was obtained, with the same tool and in the same process conditions, to inject simultaneously two specimens in cavities manufactured with different technologies.3. Obtaining an electroformed shell: the equipmentElectrodeposition [5] and [6] is an electrochemical process in which a chemical change has its origin within an electrolyte when passing an electric current through it. The electrolytic bath is formed by metal salts with two submerged electrodes, an anode (nickel) and a cathode (model), through which it is made to pass an intensity coming from a DC current. When the current flows through the circuit, the metal ionspresent in the solution are transformed into atoms that are settled on the cathode creating a more or less uniform deposit layer.The plating bath used in this work is formed by nickel sulfamate [7] and [8] at a concentration of 400 ml/l, nickel chloride (10 g/l), boric acid (50 g/l), Allbrite SLA (30 cc/l) and Allbrite 703 (2 cc/l). The selection of this composition is mainly due to the type of application we intend, that is to say, injection molds, even when the injection is made with fibreglass. Nickel sulfamate allows us to obtain an acceptable level of internal stresses in the shell (the tests gave results, for different process conditions, not superior to 50 MPa and for optimum conditions around 2 MPa). Nevertheless, such level of internal pressure is also a consequence of using as an additive Allbrite SLA, which is a stress reducer constituted by derivatives of toluenesulfonamide and by formaldehyde in aqueous solution. Such additive also favours the increase of the resistance of the shell when permitting a smaller grain. Allbrite 703 is an aqueous solution of biodegradable surface-acting agents that has been utilized to reduce the risk of pitting. Nickel chloride, in spite of being harmful for the internal stresses, is added to enhance the conductivity of the solution and to favour the uniformity in the metallic distribution in the cathode. The boric acid acts as a pH buffer.The equipment used to manufacture the nickel shells tested has been as follows:• Polypropylene tank: 600mm ×400 mm ×500 mm in size.• Three teflon resistors, each one with 800 W.• Mechanical stirring system of the cathode.• System for recirculation and filtration of the bath formed by a pump and a polypropylene filter.• Charging rectifier. Maximum intensity in continuous 50 A and continuous current voltage between 0 and 16 V.• Titanium basket with nickel anodes (Inco S-Rounds Electrolytic Nickel) with a purity of 99%.• Gases aspiration system.Once the bath has been defined, the operative parameters that have been altered for testing different conditions of the process have been thecurrent density (between 1 and 22 A/dm2), the temperature (between 35 and 55 °C) and the pH, partially modifying the bath composition.4. Obtained hardnessOne of the most interesting conclusions obtained during the tests has been that the level of hardness of the different electroformed shells has remained at rather high and stable values. In Fig. 2, it can be observed the way in which for current density values between 2.5 and 22 A/dm2, the hardness values range from 540 and 580 HV, at pH 4 ±0.2 and with a temperature of 45 °C. If the pH of the bath is reduced at 3.5 and the temperature is 55 °C those values are above 520HV and below 560 HV. This feature makes the tested bath different from other conventional ones composed by nickel sulfamate, allowing to operate with a wider range of values; nevertheless, such operativity will be limited depending on other factors, such as internal stress because its variability may condition the work at certain values of pH, current density or temperature. On the other hand, the hardness of a conventional sulfamate bath is between 200–250 HV, much lower than the one obtained in the tests. It is necessary to take into account that, for an injection mold, the hardness is acceptable starting from 300 HV. Among the most usual materials for injection molds it is possible to find steel for improvement (290 HV), steel for integral hardening (520–595 HV), casehardened steel(760–800 HV), etc., in such a way that it can be observed that the hardness levels of the nickel shells would be within the medium–high range of the materials for injection molds. The objection to the low ductility of the shell is compensated in such a way with the epoxy resin filling that would follow it because this is the one responsible for holding inwardly the pressure charges of the processes of plastics injection; this is the reason why it is necessary for the shell to have a thickness as homogeneous as possible (above a minimum value) and with absence of important failures such as pitting.Fig. 2. Hardness variation with current density. pH 4 ±0.2, T= 45 °C.5. Metallographic structureIn order to analyze the metallographic structure, the values of current density and temperature were mainly modified. The samples were analyzed in frontal section and in transversal section (perpendicular to the deposition). For achieving a convenient preparation, they were conveniently encapsulated in resin, polished and etched in different stages with a mixture of acetic acid and nitric acid. The etches are carried out at intervals of 15, 25, 40 and 50 s, after being polished again, in order to be observed afterwards in a metallographic microscope Olympus PME3-ADL 3.3×/10×.Before going on to comment the photographs shown in this article, it is necessary to say that the models used to manufacture the shells were made in a FDM rapid prototyping machine where the molten plastic material (ABS), that later solidifies, is settled layer by layer. In each layer, the extruder die leaves a thread approximately 0.15 mm in diameter which is compacted horizontal and vertically with the thread settled inmediately after. Thus, in the surface it can be observed thin lines that indicate the roads followed by the head of the machine. These lines are going to act as a reference to indicate the reproducibility level of the nickel settled. The reproducibility of the model is going to be a fundamental element to evaluate a basic aspect of injection molds: the surface texture.The tested series are indicated in Table 1.Table 1.Tested seriesSeries pH Temperature (°C)Current density (A/dm2)1 4.2 ±0.255 2.222 3.9 ±0.245 5.563 4.0 ±0.24510.004 4.0 ±0.24522.22Fig. 3 illustrates the surface of a sample of the series after the first etch. It shows the roads originated by the FDM machine, that is to say that there is a good reproducibility. It cannot be still noticed the rounded grain structure. In Fig. 4, series 2, after a second etch, it can be observed a line of the road in a way less clear than in the previous case. In Fig. 5, series 3 and 2° etch it begins to appear the rounded grain structure although it is very difficult to check the roads at thistime. Besides, the most darkened areas indicate the presence of pitting by inadequate conditions of process and bath composition.Fig. 3. Series 1 (×150), etch 1.Fig. 4. Series 2 (×300), etch 2.Fig. 5. Series 3 (×300), etch 2.This behavior indicates that, working at a low current density and a high temperature, shells with a good reproducibility of the model and with a small grain size are obtained, that is, adequate for the required application.If the analysis is carried out in a plane transversal to the deposition, it can be tested in all the samples and for all the conditions that the growth structure of the deposit is laminar (Fig. 6), what is very satisfactory to obtain a high mechanical resistance although at theexpense of a low ductibility. This quality is due, above all, to the presence of the additives used because a nickel sulfamate bath without additives normally creates a fibrous and non-laminar structure [9]. The modification until a nearly null value of the wetting agent gave as a result that the laminar structure was maintained in any case, that matter demonstrated that the determinant for such structure was the stress reducer (Allbrite SLA). On the other hand, it was also tested that the laminar structure varies according to the thickness of the layer in terms of the current density.Fig. 6. Plane transversal of series 2 (×600), etch 2.6. Internal stressesOne of the main characteristic that a shell should have for its application like an insert is to have a low level of internal stresses. Different tests at different bath temperatures and current densities were done and a measure system rested on cathode flexural tensiometer method was used.A steel testing control was used with a side fixed and the other free (160 mm length, 12.7 mm width and thickness 0.3 mm). Because the metallic deposition is only in one side the testing control has a mechanical strain (tensile or compressive stress) that allows to calculate the internal stresses. Stoney model [10] was applied and was supposed that nickel substratum thickness is enough small (3 μm) to influence, in an elastic point of view, to the strained steel part. In all the tested cases the most value of internal stress was under 50 MPa for extreme conditions and 2 MPa for optimal conditions, an acceptable value for the required application. The conclusion is that the electrolitic bath allows to work at different conditions and parameters without a significant variation of internal stresses.7. Test of the injection moldTests have been carried out with various representative thermoplastic materials such as PP, PA, HDPE and PC, and it has been analysed the properties of the injected parts such as dimensions, weight, resistance, rigidity and ductility. Mechanical properties were tested by tensile destructive tests and analysis by photoelasticity. About 500 injections were carried out on this core, remaining under conditions of withstanding many more.In general terms, important differences were not noticed between the behavior of the specimens obtained in the core and the ones from the machined cavity, for the set of the analysed materials. However in the analysis by photoelasticiy (Fig. 7) it was noticed a different tensional state between both types of specimens, basically due to differences in the heat transference and rigidity of the respective mold cavities. This difference explains the ductility variations more outstanding in the partially crystalline materials such as HDPE and PA 6.Fig. 7. Analysis by photoelasticity of injected specimens.For the case of HDPE in all the analysed tested tubes it was noticed a lower ductility in the specimens obtained in the nickel core, quantified about 30%. In the case of PA 6 this value was around 50%.8. ConclusionsAfter consecutive tests and in different conditions it has been checked that the nickel sulfamate bath, with the utilized additives has allowed to obtain nickel shells with some mechanical properties acceptable for the required application, injection molds, that is to say, good reproducibility, high level of hardness and good mechanical resistance in terms of the resultant laminar structure. The mechanical deficiencies of the nickel shell will be partially replaced by the epoxy resin that finishes shaping the core for the injection mold, allowing to inject medium series of plastic parts with acceptable quality levels.References[1] A.E.W. Rennie, C.E. Bocking and G.R. Bennet, Electroforming of rapid prototyping mandrels for electro discharge machining electrodes, J. Mater. Process. Technol.110(2001), pp. 186–196. [2] P.K.D.V. Yarlagadda, I.P. Ilyas and P. Chrstodoulou, Development of rapid tooling for sheet metal drawing using nickel electroforming and stereo lithography processes, J. Mater. Process. Technol.111 (2001), pp. 286–294.[3] J. Hart, A. Watson, Electroforming: A largely unrecognised but expanding vital industry, Interfinish 96, 14 World Congress, Birmingham, UK, 1996.[4] M. Monzón et al., Aplicación del electroconformado en la fabricación rápida de moldes de inyección, Revista de Plásticos Modernos.84(2002), p. 557.[5] L.F. Hamilton et al., Cálculos de Química Analítica, McGraw Hill (1989).[6] E. Julve, Electrodeposición de metales, 2000 (E.J.S.).[7] A. Watson, Nickel Sulphamate Solutions, Nickel Development Institute (1989).[8] A. Watson, Additions to Sulphamate Nickel Solutions, Nickel Development Institute (1989).[9] J. Dini, Electrodeposition Materials Science of Coating and Substrates, Noyes Publications (1993).[10] J.W. Judy, Magnetic microactuators with polysilicon flexures, Masters Report, Department of EECS, University of California, Berkeley, 1994. (cap′. 3).谢谢下载，祝您生活愉快！谢谢下载，祝您生活愉快！。