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英文文献翻译翻译原文题目：A study on the computer-aided measuring integration system for the sheet metal stamping die.文献出处：She C H, Chang C C, Kao Y C, et al. A study on the computer-aided measuring integration system for the sheet metal stamping dieJ. Journal of Materials Processing Technology, 2006, 177(1-3):138-141.翻译正文：(1)Metal CastingMetal casting process begins by creating a mould，which is the reverse，shape of the part we need. The mould is made from a refractory material，for example，sand. The metal is heated in an oven until it melts， and the molten metal is poured into the mould cavity. The liquid takes the shape of cavity，which is the shape Of the part. It is cooled until it solidifies. Finally，the solidified metal part is removed from the mould.A large number Of metal components in designs we use every day are made by casting. The reasons for this include：a. Casting can produce very complex geometry parts With internal cavities and hollow sections.b. It can be used to make small（few hundred grams)to very large size parts(thousands Of kilograms).c. It is economical，with very little wastage，the extra metal in each casting is remelted and re-used.d. Cast metal is isotropicit has the same physical/ mechanical properties along any direction.There are several types Of metal casting method：sand casting，permanent mould casting die casting, ceramic mould casting, vacuum casting, centrifugal casting, pressure casting, suspension casting, shell-mould casting, expendable-pattern casting (lost foam process), plaster-mould casting, investment casting (lost wax process),etc.2) Forging DieForging is, as far as we know, the oldest metalworking process. In the early dawn of civilization mankind discovered that a heated piece of metal was more easily hammered into different shapes. Forging can be defined as the working of a piece of metal into a desired shape by hammering or pressing, usually after it has been heated to improve its plasticity. In most cases, the metal to be forged is heated to its correct forging temperature, but sometimes cold-forging is done. Cold-forging is included under cold-working and is accomplished in the range from room temperature up to the critical temperature of the metal.Forgings are generally superior in mechanical properties to castings with the same chemical analysis. Therefore, parts which must withstand severe stresses are preferably made by forging, Forgings have better mechanical properties than castings for at least three reasons. First, the fiber flow lines when properly controlled and directed tend to provide higher strengths. Second, the forging process by hammering or pressing produces a dense structure usually free from voids, blow holes, or porosity. Third, the forging process helps to refine the grain size of the metal. The working of the metal breaks up coarse grains by producing a slip along crystallographic planes.In forging, the metal may be worked by:1) Drawing out. This increases length and decreases cross-sectional area.2) Upsetting. This increases cross-sectional area and decreases lengt.3) queening in closed Impression dies.The forging processes can be grouped under four principal methods as follows: smith forging; drop forging, press forging; upset forging. The sizes of the forgings produced range from 1 pound to over 200 tons. Usually steam hammers, large hydraulic presses, air hammers, or helve hammers are used.In the process of forging, in order to improve the production efficiency, is usually used to forging die. The tools necessary to produce a given forging cannot be made until the shape of the final forging has been determined. These will be considered in the following order: forging draft, parting planes, fillets and corner radii, shrinkage and die wear, mismatch of dies, tolerances, and finish allowances.Drop forging dies must withstand severe strains, resist wear, keep cracking and checking at a minimum, and have a long life under high-production conditions. In order to obtain these properties, chromium-nickel-molybdenum, chromium-nickel, or chromium-molybdenum alloy steels are used as die materials. when selecting the parting line on forgings, consideration must be given to the flow of metal and the directions of the resulting fiber flow lines. A flat parting surface in a single horizontal plane should be selected if possible, because irregular parting surfaces may create a side thrust and they add to the cost of the dies. The standard draft angle is 7 degrees since smaller draft angles cause more rapid die wear and increase the likelihood of the forgings sticking in the die. Interior surfaces require more draft, usually 10 degrees, since the forgings will shrink around those portions of the die as they cool if several blows are to be struck.No-draft forgings are used most often on nonferrous alloys. They are usually mounted in a die set and run in a forging press. Depending on the shape of the part, two or more sides of the die cavity are movable to allow the most conventional forgings and the production rates are much slower. In many cases, the parts are run once with the die not completely closed, excess flash material is removed and then the part is reheated and run a second time with the die closed completely.Although this is an expensive process, the advantage of secondary machining operations being eliminated due to the absence of the draft angles makes the overall cost of the part considerably less.翻译译文：(1)金属铸造金属铸造过程开始于创建一个模具，这是我们所需要的零件的“反向”形状。模具是由耐火材料制成的，例如，沙子。金属在烘箱中加热直到熔化，熔融金属倒入模具型腔中。液体呈腔体形状，形状为部件的形状。它被冷却直到它凝固。最后，将固化的金属部件从模具中取出。我们每天使用的大量金属部件是用铸造制造的，其原因包括：a) 铸造可以产生非常复杂的几何部件，内部空腔和空心部分。b) 它可以用来制造非常小的（几百克）到非常大的零件（几千克）。c) 它是经济的，浪费很小，每个铸件中的多余金属被重新熔化和再利用。d) 铸造金属是各向同性的，它沿任意方向具有相同的物理/机械性能。金属铸造有多种类型：砂型铸造、永久铸型铸造、陶瓷型铸造、真空铸造、离心铸造、压力铸造、悬浮铸造、壳型铸造、消失模铸造（消失模工艺）、石膏型铸造、熔模铸造（失蜡法）等。2) 锻造模具据我们所知，锻造是最古老的金属加工工艺。在文明的早期曙光中，人类发现一块被加热的金属更容易被锤击成不同的形状。锻造可以定义为通过锤击或压制将一块金属加工成期望的形状，通常是在加热以提高其塑性之后。在大多数情况下，锻造的金属被加热到其正确的锻造温度，但有时进行冷锻。冷锻包括在冷加工中，并且在从室温到金属临界温度的范围内完成。锻件在机械性能方面通常优于铸件，具有相同的化学分析。因此，必须承受严重应力的零件最好通过锻造来制造，由于至少三个原因，锻件比铸件具有更好的机械性能。首先，纤维流线在适当控制和引导时趋向于提供更高的强度。第二，锤击或压制的锻造过程产生致密的结构，通常不含空隙、吹孔或气孔。第三，锻造工艺有助于细化金属的晶粒尺寸。金属的加工通过沿晶面产生滑移来分解粗晶。在锻造过程中，金属可以通过以下方式工作：1）抽出。这增加了长度并减小了横截面积。 2）镦粗。这增加了横截面积并减小了长度。 3）封闭印模模具中的龟裂。锻造工艺可分为四种主要方法：史密斯锻造、落锤锻造、压锻、镦锻。锻件的尺寸从 1 磅到 200 吨以上。通常使用蒸汽锤、大型液压机、空气锤或重型锤。在锻造过程中，为了提高生产效率, 通常采用锻模。在确定最终锻造的形状之前，不能制造出给定锻件所必需的工具。这些将按以下顺序考虑：锻造草案，分型面、圆角和角半径、收缩和模具磨损、模具不匹配、公差和精加工余量。落料锻模在高生产条件下必须经得起剧烈的应变，耐磨，保持开裂和校核的最低限度，并具有长寿命。为了获得这些性能，使用铬-镍-钼、铬-镍或铬-钼合金钢作为模具材料。在选择锻件分型线时，必须考虑金属的流动以及由此产生的纤维流动线的方向。如果可能的话，应该选择单个水平平面中的平坦的分型表面，因为不规则的分型表面可能产生侧向推力，并且会增加模具的成本。标准牵伸角为 7 度，因为较小的牵伸角导致更快的模具磨损，并增加锻件粘附在模具中的可能性。内表面需要更多的拉力，通常是 10 度，因为如果要打几下，锻件会在模具的这些部分冷却时收缩。在有色金属合金上不经常使用牵伸锻件。它们通常安装在模具中，并在锻压机中运行。根据零件的形状，模腔的两侧或多侧是可移动的，以便允许最常规的锻件，并且生产速度要慢得多。在许多情况下，零件在模具未完全闭合的情况下运行一次，去除多余的闪光材料，然后重新加热零件并在模具完全闭合的情况下运行第二次。虽然这是一个昂贵的工艺，但由于没有牵伸角，二次加工的优点被消除，使得零件的总体成本大大降低。理解综述一、本文主要内容第一部分内容讲述了金属制造是一项将熔融金属倒入模具型腔中然后冷却后取出零件的加工工艺。金属铸造可以生产大大小小的具有各向同性的复杂零件，并且金属铸造的浪费很小，每个铸件中的多余金属被重新熔化和再利用。金属铸造主要有砂型铸造、永久铸型铸造等。第二部分内容告诉我们锻造是一项最古老的金属加工工艺之一，锻造是通过锤击或压制将一块金属加工成期望的形状的加工工艺。锻件在机械性能方面通常优于铸件，因为锻件能提供更高的强度，并且锻造过程中产生致密的结构且不含空隙、吹孔及，而且锻造工艺有助于细化金属的晶粒尺寸。在锻造过程中，金属可以通过抽出、镦粗、封闭模具中的龟裂的方式工作。锻造工艺的主要方法是史密斯锻造、落锤锻造、压锻、以及镦锻四种。在锻造过程中，为了提高生产效率, 通常采用锻模。锻模使用铬 -镍-钼、铬-镍或铬 -钼合金钢作为模具材料。锻模通常选择单个水平平面中平坦的分型表面，且标准牵伸角为 7 度。2、本文主要研究方法（手段）对金属铸造和锻造模具作了相关的阐述，分别介绍了它们的定义、优缺点、历史以及使用范围等内容，且这篇文章将两者作了比较，清晰的体现出了两者之间的不同之处，使读者能更加清楚的了解金属铸造与锻造模具。3、本文主要结论1. 金属铸造可以生产大大小小的具有各向同性的复杂零件，有大量的金属部件是用铸造制造的。2. 锻造技术历史悠久，锻件在机械性能方面通常优于铸件，通常用锻造来制造必须承受严重应力的零件。3. 锻模生产效率高，通常使用铬-镍-钼、铬-镍或铬-钼合金钢作为模具材料以获得经得起剧烈的应变、耐磨、并使用寿命长的性能。在设计锻模使应注意分型面和牵伸角的选择，通常选择单个水平表面中的平坦的面作为分型表面，标准牵伸角为 7 度。
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