材料科学导论英文阅读.doc

Chapter 1 An Overview 第一章概述1.1 Introduction1.1介绍Materials are the matter of the universe. These substances have properties that make them useful in structures, machines, devices, products, and systems. The term properties describe behavior of materials when subjected to some external force or condition. For example, the tensile strength of a metal is a measure of the materials resistance to a pulling force. The Family of Materials consists of four main groups of materials: Metals (e.g., steel), Polymers (e.g., plastics), Ceramics (e.g., porcelain), and Composites (e.g., glass-reinforced plastics). The materials in each group have similar properties and/or structures, as will be described later.材料是宇宙的物质。这些物质的特性使其有用的结构、机器设备、产品和系统。这个术语属性描述材料的行为时,受到一些外部力量或状态。例如,抗拉强度的金属是测量的材料抵抗了拉力。这个家庭的材料由四个主要群体的材料:金属(如钢)、高分子材料(例如:塑料)、陶瓷(如瓷),复合材料(例如,增强塑料)。每一组的材料有相似的性质和/或建筑物,如稍后会提到。Engineering materials is a term often used loosely to define most materials that go into products and systems. A telephone is a product that would be part of a telephone system composed of many telephones, wires, fiber optics, switches, computers, and so on. Engineering materials can also have a more specific meaning that refers to materials whose structure has been designed to develop specific properties for a given application.工程材料是一种常用的松散定义最材料,进入产品和系统。电话是一种产品,将部分电话系统由许多电话、电线、光纤、开关、电脑等。工程材料也可以有更多的特定含义是指材料的结构已经被设计来发展特性对于一个给定的应用。Engineering plastics such as polycarbonates and acetals could replace more conventional engineering materials such as steel and wood because their properties are competitive for structural components such as piping, cams, and gears. On the other hand, general-purpose plastics, such as polystyrene and vinyls, do not possess the properties to carry heavy loads but serve as packaging, upholstery, and so on.工程塑料,如polycarbonates缩醛可以代替常规,工程材料,如钢材和木材,因为它们的性质有竞争力的结构元件,如管道、视角、齿轮。另一方面,通用型塑料制品,如聚苯乙烯、乙烯基、不具有携带重物,但作为包装、室内装潢,等等。The field of materials engineering deals with the synthesis and use of knowledge (structure, properties, processing, and behavior) in order to develop, prepare, modify, and apply materials to specific needs. Materials engineers have become very much in demand as we seek to improve the efficiency of products.这个领域的材料工程”涉及的合成和使用知识结构、性能、加工、行为)为了发展、准备、修改和申请材料的具体需求”。物料工程师已经成为需求量很大寻求提高效率的产品。Materials science and engineering (MSE) has become a major field of study, one critical to many other fields. As defined by a National Academy of Sciences study, MSE involves the generation and application of knowledge relating the composition, structure, and processing of materials to their properties and uses. The science focuses on discovering the nature of materials, which in turn leads to theories or descriptions that explain how structure relates to composition, properties, and behavior. The engineering, on the other hand, deals with use of the science in order to develop, prepare, modify, and apply materials to meet specific needs. The field is often considered an engineering science because of its applied nature. Materials science and engineering is interdisciplinary or multidisciplinary, embracing areas such as metallurgy, ceramics, solid-state physics, and polymer chemistry.材料科学与工程专业(MSE)已成为一个主要的研究领域,对其他许多领域的一个关键。定义一个国家科学院的一代,MSE涉及研究和应用的相关知识的组成、结构、加工材料性能和用途。“科学”的自然材料的发现,这就导致了理论或描述解释结构与组成、性质和行为。“工程”,另一方面,利用科学为发展,制定、修改、申请材料以满足特定需求。这个领域通常是被视为一种工程应用科学,因为它的本质。材料科学与工程学科交叉或语系,冶金、建材、陶瓷等领域,固态物理、聚合物化学。Many new processes have evolved for the manufacture of engineering materials. Through these processes, coupled with the design of engineering materials, we now enjoy the benefits of superior engineering materials.We current have available for potential use in engineering structures and electronic devices about 45,000 different metallic alloys, of the order of 15,000 different polymers, and hundreds, if not thousands, of other materials that fall in the categories of wood, ceramics, fabrics, and semiconductors. An automobile alone contains several hundred different materials. A 1986 Mercedes-Benz contains 67 wt% cast iron and steel, 12 wt% fabrics, 12 wt% polymers, and 4 wt% aluminum alloys, the balance being composed of glass and other nonferrous alloys. For a 1996 Mercedes-Benz, a span of only 10 years, iron and steel use fell to 62 wt%, while polymers and aluminum alloy content increased to 18 and 6 wt%, respectively. Throughout all industries, the trend to more polymer use is evident. As you are probably aware, polymers have replaced metals in many household functions. It is thus not only the current materials available with which we must be concerned in the material selection process but also those on the horizon, particularly the new developments in the fast-growing technologies. Frequently, such material developments can be transferred to the older, more mature industries. Figure 1-1 depicts a maturity curve for a variety of materials. This curve is, to a certain degree, based on projected use and should be considered in that light. The important point that is illustrated here is that in the future we can expect to see more and more applications of polymers, ceramics, and composites. Composites are a combination of two or more materials. Fiberglass and concrete are familiar examples. Composites now fall into a new and distinct category that is being referred to by technologists as engineered materials. In the past we have selected existing materials to fit a design or application. If the fit did not work, the design was altered or different materials were selected. In the future we can expect to see more materials that are engineered to suit an application. As stated in a Specific American review article, we are now leaving the basic materials age (i.e., the stone, bronze, and iron ages), and entering the era of engineered materials.我们目前所拥有的潜力,在工程结构使用电子设备约45000名不同的金属合金、顺序的不同聚合物,数以百计的15000,如果不是成千上万的其他材料,落在类别的木头、陶瓷、面料、半导体。一辆汽车有数百个不同的材料。1986年梅赛德斯-奔驰包含67股份铸铁、钢铁、12股份面料、12股份聚合物,4股份铝合金、平衡是由玻璃等有色金属合金。对于1996年的奔驰,只有10年、钢铁使用降至62股份,而聚合物和铝合金含量增加到18 %,分别为6重。整个产业的趋势,更多的聚合物使用是显而易见的。正如你可能知道,聚合物已经取代了金属在很多家庭功能。这样不仅当前的材料,我们必须关注在材料选择过程,而且那些地平线上的新进展,特别是在快速发展的技术。通常,这样的材料的发展可以转移到老年人,更成熟的行业。图1-1描绘一个成熟的曲线为各种各样的材料。该曲线,在某种程度上,根据使用和应考虑的光。最重要的一点,就是说明这是,在未来,我们可以看到越来越多的应用和复合材料、陶瓷、高分子聚合物。复合材料是一种由两个或更多的材料。玻璃纤维和混凝土熟悉的例子。现在落入一个新的材料,不同类别的被称为技术作为工程材料。在过去,我们已经选择了现有材料符合设计和应用。如果适合都不工作了,设计变更、不同材料的选择。在不久的将来,我们会看到更多的材料,制造适合一个应用程序。正如一个特定的美国篇,现在只剩下的基本材料时代(例如,石、铜、铁时代),并进入了时代的工程材料。Figure 1-1 Materials maturity curve图1-1材料成熟的曲线It is both historical and technical interest to follow the development of materials for aircraft construction, because no other situation have the properties of strength, weight, and operating temperature been so interrelated and important. The first all-metal monoplane, designed by Hanna Reissner of Germany, which first flew in 1912, had wings of pure aluminum. In the early 1930s riveted aluminum alloy skin was first used for airframe construction and was the predominant fuselage material until the advent of supersonic aircraft. The Boeing 757, for example, contains 80% aluminum, 12% steel, and 3% composites. But aluminum alloys are limited to temperature of about 175oC. The Concorde, the only supersonic commercial aircraft in use today, and military aircraft such as SR-71 surveillance aircraft (Mach 3), have titanium alloy fuselages. Starting with the Harrier, an aircraft designed in the 1970s at McDonnell Aircraft Company, much of the aluminum support structure was replaced by lighter, and stronger carbon-epoxy composites. Strong, lightweight composites are currently playing a major role in nonmilitary aircraft. The Voyager achieved its global circuit without refueling, in large part due to the use of graphite-epoxy composites in conjunction with the honeycomb structures. Predictions are that we will see many more composites in the aircraft of the 21st century, not only in the fuselage and support structures but in the jet engine itself.它既是历史与技术发展的兴趣跟飞机结构材料,因为没有其他情况的强度、重量、操作温度是如此相互联系和重要的。第all-metal单翼式的设计,由汉纳Reissner德国首飞在1912年,有翅膀的纯铝。在30年代初期铆接铝合金皮肤最初是用于机身结构,是时代的到来,机身材料到超音速飞机。这架波音757;例如,包含了80%,12%的钢铝复合材料、3%。但铝合金局限于温度约175oC。协和超音速的商用客机,只有在使用军用飞机今天,如SR-71监视飞机(3),马赫钛合金机身。从一架飞机的设计,在20世纪70年代,美国航空公司,大部分的铝支撑结构被减轻,更carbon-epoxy复合材料。强、轻便的材料中扮演主要角色目前非军事飞机。这个旅行者实现全球电路没有加油,这在很大程度上是由于使用复合的graphite-epoxy会同蜂窝结构。预测,我们将看到更多的复合材料在民用航空器的21世纪,不仅在机身和支护结构,但在喷气发动机的本身。When we examine the structure of the current jet engine we find that advances made in the alloys of nickel, cobalt, and chromium, called superalloys, have permitted the increase in operating temperature necessary for increased engine efficiency, which translates into faster travel speeds and increased fuel economy. One alternative would be to go to higher-melting-point metals such as tantalum, niobium, molybdenum, and tungsten. But these metals have the disadvantages of being very reactive to gases at elevated temperatures, hence requiring some kind of protective surface layer. Experiments with ceramic coatings have not been successful. Therefore, materials engineers are currently working on the development ceramic and ceramic composite materials for use in the hottest parts of the engine. Useful alloys developed to date are limited to about 1040oC, while ceramics can retain their strength to 1650C and are potentially useful to 2760C.当我们检视结构现状的基础上,我们发现了喷气发动机的镍合金、钴、铬合金,允许,称为操作温度的增加,增加引擎效率所需的旅行速度更快,转译为提高燃油经济性。一个你可以去higher-melting-point金属钽、铌、钼、钨。但是这些金属的弊端是非常活泼,在高温气体,因此需要一种防护表层。实验与陶瓷涂层尚未成功。因此,物料工程师正在开发陶瓷、陶瓷复合材料用于最热的部分的引擎。有用的合金发展到大约1040oC日期是有限的,而他们的力量能保留陶瓷C和潜在几百C 2760有用。Automotive engineers are also participating in the development of ceramic and ceramic composite materials. Approximately one-third of the energy generated in an internal combustion engine is lost in the cooling process necessary to prevent distortion of the metallic parts. Piston rods and ceramic cylinder liners, predicted by some to be used before the year of 2000, would lessen the amount of cooling required, while a ceramic engine block must, however, await the development of less brittle ceramic materials.汽车工程师也参与了发展陶瓷和陶瓷复合材料。约三分之一的能量产生在内燃机迷失在冷却过程中需要防止变形的金属部件。活塞棒和陶瓷圆柱衬垫,预测由一些在2000年,会减少,同时要求的冷却陶瓷柴油机机体必须,但是,等待开发更少的脆性陶瓷材料。1.2 The Materials CycleTo better understand materials engineering, it is useful to view the materials cycle. The materials cycle can be broken into phases as shown in Figure 1-2. An explanation of each of the stages listed in the figure will provide you with insight into the importance of materials, how they affect our lives, and their total impact on society.12材料的循环为了更好的理解材料工程,它是有用的材料。材料的周期可以分解成不同阶段如图1-2。一种解释每个阶段中列出的人物将会为您提供深入的重要性,他们的资料,他们会影响我们的生活总对社会的影响。Figure 1-2 Materials Cycle图1-2材料的循环1.2.1 Extracting Raw Materials1.2.1提取原料Some elements, in the form of solid materials, are readily available to use, such as gold. Pure carbon in the crystalline form of diamond, the hardest known material, also takes little processing. But other elements are locked in the earth, ocean, or atmosphere.It is often necessary to mine ore to obtain raw materials. Aluminum (Al), for example, is combined with oxygen (O) to form alumina (Al2O3). It takes large amounts of electricity to extract Al from bauxite (Al2O3) ore. It takes 95% less energy to produce aluminum by recycling scrap aluminum products.Some materials go through all stages from extraction of raw materials to production of finished parts by the same producers. For example, production of bulk polymers (plastic, rubber, paint, adhesives) is usually done by materials makers known as polymer manufacturers. These manufacturers are often located near oil refineries because most plastics are petroleum based. The manufacturer begins with raw materials such as crude oil, natural gas, trees, and cotton to make chemical compounds such as ethane, trichloromethane, hydrogen fluoride, and ethylene chloride. From these raw materials, monomers (single molecules) are produced and include ethylene, methylmethacrylate, and vinyl chloride. Through heat, pressure, and the addition of chemicals (catalysts), the monomers are polymerized to form long-chain polymers (synthesis). The final polymer (resin) is a bulk virgin material ready to go to the next stage of production.某些元素的形式,是现成固体材料使用,如金。在水晶形体的纯碳的钻石,最难的已知资料,也需要一点加工。但是其它元素被锁在地球的大气、海洋、或。我通常是必要的,获得原材料铁矿石。铝)为例,结合氧(11)形成氧化铝(氧化铝)。它需要大量的电提取铝是从铝土矿(氧化铝)矿床。它以较少的能源生产95%铝废品回收铝产品。有些材料穿过所有的阶段,从原料提取到生产完成部分相同的生产商。例如,生产的聚合物(塑胶、橡胶、涂料、胶粘剂)通常是由材料制造商称为聚合物制造商。这些厂家通常靠近炼油厂,因为大多数塑料石油基础。制造商始于原料,例如原油、天然气、树木、棉使等化合物trichloromethane、氢氟乙烯、环氧氯甲基化反应,。从这些原料、单体(单分子)产生和包括乙烯、methylmethacrylate、氯乙烯。通过热、压力、添加化学品(催化剂)、单体长链聚合物具有形式(综合)。最后的聚合物(树脂)是一个大部分“处女”准备走到下一个阶段的生产。1.2.2 Creating Bulk Materials, Components, and Devices1.2.2创建散装材料、建筑构配件,和设备Bulk materials are the products of synthesis, materials extraction, refinement, and processing. There are many bulk materials with which you are familiar, such as fir plywood, sheet steel, acrylic tubing, window glass, copper wire, and concrete. Bulk materials are usually made in large quantities through continuous processing and then supplied to manufacturers of components and devices.Components include gears, electrical wires, screws, nuts, jet engine turbine blades, brackets, levers, and the thousands of constituent parts that go into many products and systems. Devices, which include microprocessors, resistors, switches, and heating elements, are usually more complex than components and are designed to serve a specific purpose. Products are individual units, such as roller-blade skate sets, television sets, chairs, and telephones. Systems are an aggregate of products, components, and devices. For example, a telephone system is made up of millions of products (e.g., telephones, microwave transmitters, and computers), components (e.g., optical fiber, copper wire, and lasers), and devices (e.g., switches, relays, and microprocessors).While also dealing with atoms and molecules, materials processing includes control of structure at higher levels of aggregation and may sometimes have an engineering aspect. Materials processing will yield bulk materials such as nylon tubing, individual components such as ceramic jet nozzles, devices such as semiconductors for computers, structures such as automobile frames, and systems such as fiber-optic communications systems.散装材料的合成、材料的产品、加工和处理的提取。有许多大宗物资你所熟悉的,如杉木胶合板、钢板、丙烯酸管材、橱窗玻璃、铜丝、铝和混凝土。散装材料通常是在大批量连续处理,然后通过提供的组件和设备制造商。组件包括:齿轮、电线、螺丝、螺帽、喷气发动机涡轮叶片、支架、杠杆,成千上万的组成部分,走到许多产品和系统。设备,包括微处理器、电阻、开关、加热元件,通常更复杂部件,设计为一个特定的目的。产品有个别单位,例如roller-blade滑台、电视机、椅子,和电话。系统是一个集合的产品、零部件和设备。例如,一个电话系统是由成千上万的产品(如电话、微波发射器,电脑)、元件(例如,光纤、铜丝、铝、激光)、设备(如、开关、继电器、微处理器)。同时处理的原子和分子,材料处理”,包括控制结构在更高水平的集合,有时可能会有一个工程方面”。材料加工等大宗物资产量尼龙管、个别元件,如陶瓷喷射喷嘴、半导体器件,如电脑、结构,如汽车框架,和系统,如光纤通信系统。1.2.3 Manufacturing Engineered Materials1.2.3制造工程材料The new generation of engineering materials are often designed materials; they have been engineered to provide designated properties. In other words, instead of designers selecting from a list of available materials, they may specify the desired properties for their needs, and then rely on materials engineers and technologists to create materials to suit the need. Advanced composites are examples of engineered materials because engineers and technicians determine how reinforcing fibers should be aligned to withstand the stresses that a product will encounter under service conditions. These composites may be made of plastic resins that can withstand higher temperatures than general-purpose plastics. Advanced ceramics, one class of engineered materials, may be tougher than the normally brittle ceramics. Figure 5-7 shows the technique for manufacturing an engineered ceramic: chemical vapors of silicon carbide form a matrix as they are infiltrated into reinforcing fibers of silicon carbide for net-shape advanced ceramic composite parts.A new group of engineered materials is smart materials, a term referring to a variety of liquids and solids that have the ability at a predetermined condition to sense stresses and respond to alter their properties. For example, smart glass will darken when an electrical current is passed through a laminated grid in the glass. Electrical current can also thicken certain fluids. Optical fibers, metal fibers, and electrorheological (ER) fluids inserted into solids such as plastic composites, aluminum sheet, or concrete can sense stresses and cracking to provide early warning of probable failure. These fibers might be used in engineering applications such as insertion into aircraft wings and highway bridges to provide early warning of failure. Fibers could also serve to change the stiffness of automotive springs, helicopter blades, or golf clubs.In the search for smart materials, biomimicking has been employed to study nature and attempt to mimic its wonders. Examples of biomimickry include efforts to reproduce the way that spiders produce very strong fibers and the procedures used by mollusks in building their shells, which may lead to better techniques for fabricating integrated circuits for computers and microprocessors.新一代的工程材料通常材料;他们已经改造提供指定的属性。换句话说,而不是从列表中选择的设计师的材料,他们可能可以指定目标特性,并对其需求依赖于材料工程专业创造材料的需要。先进复合材料工程材料的例子,因为工程师和技术员决定如何增强纤维应该对齐能够承受的压力下的产品将会遇到使用条件。这些材料可能使树脂胶,能承受温度高于通用型塑料。先进的陶瓷,其中一类的工程材料,可能比正常的脆性陶瓷。图5-7显示技术,制造一个工程陶瓷:化学蒸汽碳化硅形成一个矩阵,因为它们潜入增强纤维的碳化硅陶瓷复合部件为近净先进。一群新工程材料是智能材料的一个术语,指各种液体和固体,有能力在预定的条件下应力和回应感觉改变自己的特性。例如,智能玻璃会变暗时,电流是通过一层玻璃格子。电流也会加厚一定的液体。光纤、金属纤维、电流变材料(ER)流体插入固体如塑料复合材料、铝板、混凝土开裂,能感受到压力和失败的可能性提供早期预警。这些纤维可能被用来在工程应用,如插入机翼和高速公路的桥梁,以提供早期预警的失效。纤维也可以为改变汽车的弹簧的刚度、直升机的叶片,或高尔夫球杆。在寻找智能材料,biomimicking已被用来研究,试图模仿大自然的奇迹。biomimickry的例子包括努力再现方式,蜘蛛产生很强的纤维和程序所使用的软体动物的壳大厦,这可能导致更好的制作技术的集成电路、微处理器的电脑。1.2.4 Fabricating Products and Systems1.2.4制造产品和系统Once engineering materials have been manufactured, they are assembled into many useful products and systems. New fabricating techniqu