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制造业与材料生产
第一单元    制造业的定义
制造业可以定义为转变成有用的产品的原材料通过使用最简单和便宜的方法。它不及如此，也是处理一些原材料和获得所需的产品。实际上,这是最重要的去实现这个目标通过使用最简单的,最快的,最有效的方法。如果使用低效率的技术,生产制造成本的部分将会很高,部分将竞争不比其它制造商生产的类似零件。此外,生产时间应尽可能短,以此获得一个更大的市场份额。
制造业的作用是确定和定义设备、工具和流程需要转换所需产品的设计变成现实在一个有效的方式。换句话说,它的任务是找出最合适的、最优的组合,和方法机械、材料需要实现经济和无故障的生产。因此, 制造业必须有一个强大的背景材料和最新的机械以及开发能力分析解决方案和备选方案为开放式问题经验丰富的制造业。这是除了拥有一个健全的知识的理论和实践方面的各种生产方法。
第二单元   设计材料和生产
一个产品的成本取决于原材料，设备和劳动力成本，管理，销售，仓储物流，和开销。机器和劳工成本联系和弥补，随着原材料费用，生产成本的散装。当一种材料的选择，工艺，包括机械，经常被指定，或者，如果机器是可用的，原材料，可以机加工，可以利用。可以说，经济生产的目的是在产品利润。这意味着成本必须是可接受的和竞争；同时，对产品的要求必须存在或必须创建。
生产效率
由于机床的使用，有着使机器更有效的结合操作和转移的技能更多的机器一个个渐进的趋势，从而减少时间和劳动。为了满足这些需求，机床已成为复杂的在设计和控制。许多机器已建成了自动功能，有的是完全自动的。这一技术的发展使人们有可能以较低的劳动力成本，是任何社会都希望享受较高的生活水平基本达到高生产速率。计算机辅助设计与制造是进步的重要步骤。
随着生产机械的发展，制造质量必须保持。在制造业务需求，尺寸控制保持提供是可互换的，提供最佳的运作服务备件的质量和准确性。任何大批量生产的零件数量必须适合在一个给定的组件。由可互换的零件产品的快速组装，成本低，易维修保养。保持这种尺寸的控制，检验设备必须提供适当的。三个标准来确定经济生产:
(1)功能，简单的设计,有适当的审美品质。
(2)材料的选择,代表了最佳妥协在物理性能、外观、成本及和易性或可加工性。
(3)选择的生产流程,将产生一个产品没有更多的准确性或更好的表面光洁度比必要的和最低的单位成本。
产品工程和设计
该产品的设计与制造材料，重要的是与工程有竞争力。对于任何产品可以指定一个更强大，更耐腐蚀，或更长的生命物质，例如，制造业不能忽视经济生产的机会的义务。这导致了工程价值，这是更便宜的材料或消除替代昂贵的材料或不必要的操作。
产生更高的精度、更昂贵的机器工具和操作是必要的，更高技能的劳动是必需的，并拒绝部分会越来越多。产品的设计不应比服务要求更高的精度。一个好的设计了是要整理或涂布操作的考虑，因为一个产品往往是判断外观以及功能和操作。许多产品，如那些由彩色塑料或其他特殊材料，因为外表更实用，在大多数情况下，这部分的功能是决定因素。这是特别真实，强度大，耐磨，耐腐蚀，重量，或遇到限制。
大批量生产的零件的设计应该适应大规模生产类型的机器。因为每当一个部分被加载,存储,或加载到另一个机器, 相关成本可能不增加价产品值。
第三单元    工程材料
在产品的设计和制造，它是材料和工艺理解的本质。材料有很大的不同的物理性能，可加工性的特点，形成的方法，和可能的使用寿命。设计师应选择经济的材料和工艺是最适合的产品考虑这些事实。
工程材料有两种基本类型:金属或非金属。非金属材料分为有机物质。因为这些是非金属材料以及纯金属及合金,相当多的研究是要选择合适的一个。
一些商业材料在自然界存在的元素。例如,天然化合物的金属,如氧化物、硫化物、或碳酸盐,必须经过分离或精炼操作之前他们可以进一步加工。一旦分开,他们必须有一个原子结构在常温下是长期稳定的。在金属加工,铁是最重要的自然因素。纯铁几乎没有商业用途在纯净,但当与其他元素结合成另一种金属成为领先的工程金属。的有色金属,如铜、锡、锌、镍、镁、铝、铅、和其他人都扮演了重要的角色，在我国的经济,每一个都有特定的性能和用途。
制造业需要的工具和机器才能产生经济。经济依赖于选择适当的机器，或给一个满意的成品,其最佳操作性能和最大的劳动和支持设施。选择是影响待生产的产品的数量。通常有一个机器最适合一个特定的输出。在小批量或作业车间制造、通用机械如车床,钻床,铣床可能被证明是最好的,因为他们是适应性强,具有较低的初始成本,需要较少的维护,并具有灵活性,以满足不断变化的条件。然而,一个特殊用途的机器应该考虑大量的标准化产品。如活塞或汽缸盖表面研磨,将做这项工作做好、做快、成本低，一个机器应建立一种类型的工作或操作。
许多专用的机器或工具不同于标准的类型,因为他们已经构建出他们的一些技能的操作。一个简单的螺栓可以在车床或自动螺丝机上生产。车床操作员不仅必须知道如何使螺栓，也必须足够熟练的操作机器。在自动机床的操作顺序和运动控制的工具是由凸轮控制,每一项生产都是与前一个相同。这种“技能迁移”的自动化机器，允许操作人员技能稍逊一筹,但需要更大的技能运营商在监督和维护。它常常是不经济的,因为成本可能是昂贵的。
对于一个给定的产品最好的机器或过程的选择需要的生产方法。必须考虑的因素是产量、成品的质量, 这件工作的优点和设备能力的局限性。大部分可以通过几种方法生产,但通常有一种方法是最经济的。
 

                   Unit 1    Definition of Manufacturing
Manufacturing can defined as the transformation of raw materials into useful products through the use of the easiest and least-expensive methods. It is not enough, therefore, to process some raw materials and obtain the desired product. It is, in fact, of major importance to achieve that goal through employing the easiest, fastest, and most efficient methods. If less efficient techniques are used, the production cost of the manufactured part will be high, and the part will not be as competitive as similar parts produced by other manufacturers. Also, the production time should be as short as possible to enable to enable capturing a larger market share.
The function of a manufacturing engineer is, therefore, to determine and define the equipment, tools, and processes required to convert the design of the desired product into reality in an efficient manner. In other words, it is the engineer is task to find out the most appropriate, optimal combination of machinery, materials, and methods needed to achieve economical and trouble-free production. Thus, a manufacturing engineer must have a strong background in materials and up-to-date machinery as well as the ability to develop analytical solutions and alternatives for the open-ended problems experienced in manufacturing. This is in addition to having a sound knowledge of the theoretical and practical aspects of the various manufacturing methods.
              Unit 2    Design Materials and Production
The cost of a product depends on raw materials, production costs for machines and labor, management and sales, warehousing and logistics, and overhead. Machine and labor costs are inexorably related and make up, along with raw materials expenditures, the bulk of production costs. When a material is chosen, the process, including the machine, is frequently specified, Alternatively, if a machine is available, the raw material that can be processed on that machine may be utilized. One could say that the purpose of economical production is to product at a profit. This infers that the cost must be acceptable and competitive; also, a demand for the product must exist or must be created.
Efficiency in Production
Since the first use of machine tools, there has been a gradual trend toward making machines more efficient by combining operations and by transferring more skill to the machine, thus reducing time and labor. To meet these needs, machine tools have become complex both in design and in control. Automatic features have been built into many machines, and some are completely automatic. This technical technical development has made it possible to attain the high production rate with low labor cost that is essential for any society wishing to enjoy high living standards. Computer-aided design and manufacturing are significant steps of progress.
Along with the development of production machines, the quality in manufacturing must be maintained. Quality and accuracy in manufacturing operations demand that dimensional control be maintained to provide parts that are interchangeable and give the best operating service. For mass production, any one of a quantity of parts must fit in a given assembly. A product made of interchangeable parts is quickly assembled, lower in cost, and easily serviced serviced. To maintain this dimensional control, appropriate inspection facilities must be provided.
Three criteria that determine economical production are:
(1) A functional but simple design that has appropriate aesthetic quality.
(2) A material choice that represents the best compromise among physical properties, appearance, cost, and workability or machinability.
(3) Selection of the manufacturing processes that will yield a product with no more accuracy or better surface finish than necessary and at the lowest possible unit cost.
Product Engineering and Design
     It is important that the product be designed with material, manufacturing, and engineering to be competitive. For any manufactured product it is possible to specify a stronger, a more corrosion-resistant, or a longer life material, for example, but it is the engineer is obligation not to overlook the opportunity of economical production. This leads to value engineering, which is the substitution of cheaper materials or elimination of costly materials or of unnecessary operations.
     To produce parts of greater accuracy, more expensive machine tools and operations are necessary, more highly skilled labor is required, and rejected parts may be more numerous. Products should not be designed with greater accuracy than the service requirements demand. A good design incensed consideration of a finishing or coating operation, because a product is often judged for appearance as well as function and operation. Many products, such as those made from colored plastics or other special materials, are more saleable because of appearance. In most cases the function of the part is the deciding factor. This is particularly true where great strength, wear, corrosion, resistance, or weight limitations are encountered.
     For mass produced parts the design should be adaptable to mass production-type machines with a minimum of different setups. Whenever a part is loaded, stored, and reloaded into another machine, costs are involved that may not add value to the product.
                   Unit 3   Engineering Materials
     In the design and manufacture of a product, it is essential that the material and the process be understood. Materials differ widely in physical properties, machinability characteristics, methods of forming, and possible service life. The designer should consider these facts in selecting an economical material and a process that is best suited to the product.
     Engineering materials are of two basic types: metallic or nonmetallic. Nonmetallic materials are further classified as organic substances. Since these is an infinite number of nonmetallic materials as well as pure and alloyed metals, considerable study is necessary to choose the appropriate one.
     Few commercial materials exist as elements in nature. For example, the natural compounds of metals, such as oxides, sulfides, or carbonates, must undergo a separating or refining operation before they can be further processed. Once separated, they muse have an atomic strucyure that is stable at ordinary temperatures over a prolonged period. In metal working, iron is the most important natural element. Iron has little commercial use in its pure state, but when combined with other elements into various allcys it becomes the leading engineering metal. The nonferrous metals, including copper, tin, zinc, nickel, magnesium, aluminum, lead, and others all play an important part in our economy; each has specific properties and uses.
     Manufacturing requires tools and machines that can produce economically and accurately. Economy depends on the proper selection of the machine or process that will give a satisfactory finished product, its optimum operation, and maximum performance of labor and support facilities. The selection is influenced by the quantity of items to be produced. Usually there is one machine best suited for a certain output. In small-lot or job shop manufacturing, general-purpose machines such as the lathe, drill press, and milling machine may prove to be the best because they are adaptable, have lower initial cost, require less maintenance, and possess the flexibility to meet changing conditions. However, a special-purpose machine should be considered for large quantities of a standardized product. A machine built for one type of work or operation, such as the grinding of a piston or the surfacing of a cylinder head, will do the job well, quickly, and at low cost with a semiskilled operator.
      Many special-purpose machines or tools differ from the standard type in that they have built into them some of the skill of the operator. A simple bolt may be produced on either a lathe or an automatic screw machine. The lathe operator must know not only how to make the bolt but must also be sufficiently skilled to operate the machine. On the automatic machine the sequence of operations and movements of tools are controlled by cams and stops, and each item produced is identical with the previous one. This “transfer of skill” into the machine, or automation, allows less skillful operators but does require greater skill in supervision and maintenance. Often it is uneconomical to make a machine completely automatic, because the cost may because prohibitive.
      The selection of the best machine or process for a given product requires knowledge of production methods. Factors that must be considered are volume of production, quality of the finished product, and the advantages and limitations of the equipment capable of doing the work. Most parts can be produced by several methods, but usually there is one way that is most economical.