材料科学与工程专业英语课文翻译(1,2,3,10).

United 1 材料科学与工程

材料在我们的文化中比我们认识到的还要根深蒂固。如交通、房子、衣物,通讯、娱乐和食物的生产,实际上,我们日常生活中的每一

部分都或多或少地受到材料的影响。历史上社会的发展、先进与那些能满足社会需要的材料的生产及操作能力密切相关。实际上,早期的文明就以材料的发展程度来命名,如石器时代,铜器时代。早期人们能得到的只有一些很有限的天然材料,如石头、木材、粘土等。渐渐地,他们通过技术来生产优于自然材料的新材料,这些新材料包括陶器和金属。进一步地,人们发现材料的性质可以通过加热或加入其他物质来改变。在这点上,材料的应用完全是一个选择的过程。也就是说,在一系列非常有限的材料中,根据材料的优点选择一种最适合某种应用的材料。直到最近,科学家才终于了解材料的结构要素与其特性之间的关系。这个大约是过去的60 年中获得的认识使得材料的性质研究成为时髦。因此,成千上万的材料通过其特殊的性质得以发展来满足我们现代及复杂的社会需要。很多使我们生活舒适的技术的发展与适宜材料的获得密切相关。一种材料的先进程度通常是一种技术进步的先兆。比如,没有便宜的钢制品或其他替代品就没有汽车。在现代,复杂的电子器件取决于所谓的半导体零件.

材料科学与工程有时把材料科学与工程细分成材料科学和材料工程学科是有用的。严格地说,材料科学涉及材料到研究材料的结构和

性质的关系。相反,材料工程是根据材料的结构和性质的关系来设

计或操纵材料的结构以求制造出一系列可预定的性质。从功能方面

来说,材料科学家的作用是发展或合成新的材料,而材料工程师是利用已有的材料创造新的产品或体系,和/或发展材料加工新技术

。多数材料专业的本科毕业生被同时训练成材料科学家和材料工程师。“structure”一词是个模糊的术语值得解释。简单地说,材料

的结构通常与其内在成分的排列有关。原子内的结构包括介于单个原子间的电子和原子核的相互作用。在原子水平上,结构包括原子或分子与其他相关的原子或分子的组织。在更大的结构领域上,其包括大的原子团,这些原子团通常聚集在一起,称为“微观”结构,

意思是可以使用某种显微镜直接观察得到的结构。最后,结构单元可以通过肉眼看到的称为宏观结构。

“Property” 一词的概念值得详细阐述。在使用中,所有材料对外部的刺激都表现出某种反应。比如,材料受到力作用会引起形变,或者抛光金属表面会反射光。材料的特征取决于其对外部刺激的反应程度。通常,材料的性质与其形状及大小无关。实际上,所有固体材料的重要性质可以概括分为六类:机械、电学、热学、磁学、光学和腐蚀性。对于每一种性质,其都有一种对特定刺激引起反应的能

力。如机械性能与施加压力引起的形变有关,包括弹性和强度。对于电性能,如电导性和介电系数,特定的刺激物是电场。固体的热学行为则可用热容和热导率来表示。磁学性质表示一种材料对施加的电场的感应能力。对于光学性质,刺激物是电磁或光照。用折射和反射来表示光学性质。最后,腐蚀性质表示材料的化学反应能力。除了结构和性质,材料科学和工程还有其他两个重要的组成部分,即加工和性能。如果考虑这四个要素的关系,材料的结构取决于其如何加工。另外,材料的性能是其性质的功能。因此,材料的加工、结构、性质和功能的关系可以用以下线性关系来表示:加工——结构——性质——性能。

为什么研究材料科学与工程?为什么研究材料科学与工程?许多应用科学家或工程师,不管他们是机械的、民事的、化学的或电子的领域的,都将在某个时候面临材料的设计问题。如用具的运输、建筑的超级结构、油的精炼成分、或集成电路芯片。当然,材料科学家和工程师是从事材料研究和设计的专家。

很多时候,材料的问题就是从上千个材料中选择出一个合适的材料。对材料的最终选择有几个原则。首先,现场工作条件必须进行表征。只有在少数情况下材料在具有最优或理想的综合性质。因此,有必要对材料的性质进行平衡。典型的例子

是当考虑材料的强度和延展性时,而通常材料具有高强度但却具有低的延展性。这时对这两种性质进行折中考虑很有必要。其次,选择的原则是要考虑材料的性质在使用中的磨损问题。如材料的机械性能在高温或腐蚀环境中会下降。最后,也许是最重要的原则是经济问题。最终产品的成本是多少?一种材料的可以有多种理想的优越性质,但不能太昂贵。这里对材料的价格进行折中选择也是可以的。产品的成本还包括组装中的费用。工程师与科学家越熟悉材料的各种性质、结构、功能之间的关系以及材料的加工技术,根据以上的几个原则,他或她对材料的明智选择将越来越熟练和精确。

Unit 2 Classification of Materials

Solid materials have been conveniently grouped into three basic classifications: metals, ceramics, and polymers. This scheme is based primarily on chemical makeup and atomic structure, and most materials fall into one distinct grouping or another, although there are some intermediates. In addition, there are three other groups of important engineering materials—composites, semiconductors, and biomaterials.

译文:固体材料被便利的分为三个基本的类型:金属,陶瓷和聚合物。这个分类是首先基于化学组成和原子结构来分的,大多数材料落在明显的一个类别里面,尽管有许多中间品。除此之外,有三类其他重要的工程材料-复合材料,半导体材料和生物材料。

Composites consist of combinations of two or more different materials, whereas semiconductors are utilized because of their unusual electrical characteristics; biomaterials are implanted into the human body. A brief explanation of the material types and representative characteristics is offered next.

译文:复合材料由两种或者两种以上不同的材料组成,然而半导体由于它们非同寻常的电学性质而得到使用;生物材料被移植进入人类的身体中。关于材料类型和他们特殊的特征的一个简单的解释将在后面给出。

METALS

Metallic materials are normally combinations of metallic elements. They have large numbers of nonlocalized electrons; that is, these electrons are not bound to particular atoms. Many properties of metals are directly able to these electrons.

be bound to 被约束于。be attribute to 归属于。。归因于。。

译文:金属材料通常由金属元素组成。它们有大量无规则运动的电子。也就是说,这些电子不是被约束于某个特定的原子。金属的许多性质直接归属这些不规则运动的电子。

Metals are extremely good conductors of electricity and heat and are not transparent to visible light; a polished metal surface has a lustrous appearance. Furthermore, metals are quite strong, yet deformable, which accounts for their extensive use in structural applications.

科技英语在讲述科学真理的时候通常用主动语态。如: Metals are extremely good conductors of electricity Deformable ?

译文:金属是十分好的电和热的导体,它们对可见光不透明;一个抛光的金属表面有光辉的外表。除此之外,金属是十分硬的,也是可变

形的,这个性质解释了它们广泛使用在结构方面的应用。CERAMICS

Ceramics are compounds between metallic and nonmetallic elements; they are most frequently oxides, nitrides, and carbides. The wide range of materials that falls within this classification includes ceramics that are composed of clay minerals, cement, and glass.

that引导的定语从句

译文:陶瓷是介于金属和非金属元素之间的化合物;它们通常是氧化物,氮化物和碳化物。落在这个分类种类中的宽的材料范围包括陶瓷,它们由粘土矿物,水泥和玻璃组成。

These materials are typically insulative to the passage of electricity and heat, and are more resistant to high temperatures and harsh environments than metals and polymers. With regard to mechanical behavior, ceramics are hard but very brittle.

more…. Than…..

with regard to….

译文:这些材料是典型的电和热的绝缘体,并且它们比金属和聚合物更加耐高温和耐苛刻的环境。至于机械性能,陶瓷是硬的但是却很脆。

POLYMERS

Polymers include the familiar plastic and rubber materials. Many of them are organic compounds that are chemically based on carbon, hydrogen, and other nonmetallic elements; furthermore, they have very large molecular structures. These materials typically have low densities and may be extremely flexible.

译文:聚合物包括常见的塑料和橡胶材料。它们中的大多数是有机化合物,这些化合物是以化学的方法把碳、氢和其他非金属元素组合而成。因此,它们有非常大的分子结构。这些材料通常有低的密度并且可能十分柔软。

COMPOSITES

A number of composite materials have been engineered that consist of more than one material type. Fiberglass is a familiar example, in which glass fibers are embedded within a polymeric material.

more than…

译文:许多复合材料被作用工程使用,它们由至少一种类型的材料组成。玻璃丝是一个熟悉的例子,玻璃纤维被埋入聚合物材料中。

A composite is designed to display a combination of the best characteristics of each of the component materials. Fiberglass acquires strength from the glass and flexibility from the polymer. Many of the recent material developments have involved composite materials.

译文:为了联合显示每一种组分材料最好的特性,一种复合材料被设计出来。玻璃丝从玻璃中获得强度并且从聚合物中获得柔软性。最近发展中的绝大多数材料包含了复合材料。

SEMICONDUCTORS

Semiconductors have electrical properties that are intermediate between the electrical conductors and insulators. Furthermore, the electrical characteristics of these materials are extremely sensitive to the presence of minute concentrations of impurity atoms, which concentrations may be controlled over very small spatial regions.

be sensitive to 对…敏感的

译文:半导体有电的性质,它们是介于电导体和绝缘体之间的中间物。除此之外,这些材料的电学性质对微量杂质原子的存在十分敏感,杂质原子浓度可能只是在一个十分小的区域内可以控制。

The semiconductors have made possible the advent of integrated

circuitry that has totally revolutionized the electronics and computer industries (not to mention our

lives over the past two decades.

译文:这些半导体使得集成电路的出现变得可能,在过去20多年间,这些集成电路革新了电子装置和计算机工业(更不用说我们的生活。

BIOMATERIALS

Biomaterials are employed in components implanted into the human

body for replacement of diseased or damaged body parts. These materials must not produce toxic substances and must be compatible with body tissues (i.e., must not cause adverse biological reactions.

译文:生物材料被应用于移植进入人类身体以取代病变的或者损坏的身体部件。这些材料不能产生有毒物质而且必须同人身体器官要相容(比如,不能导致相反的生物反应。

All of the above materials—metals, ceramics, polymers,

composites, and semiconductors—may be used as biomaterials. For example, some of the biomaterials such as CF/C (carbon fibers/carbon and CF/PS (polysulfone are utilized in artificial hip replacements.

译文:所有以上材料-金属,陶瓷,聚合物,复合材料和半导体材料可能用作生物材料。比如,如CF/C和CF/PS(聚砜这些生物材料被用作人工肾的取代物。

ADVANCED MATERIALS

Materials that are utilized in high-technology (or high-tech applications are sometimes termed advanced materials. By high technology we mean a device or product that operates or functions using relatively intricate and sophisticated principles; examples include electronic equipment (VCRs, CD players, etc., computers, fiberoptic systems, spacecraft, aircraft, and military rocketry.

译文:用在高科技中的材料有时被称作先进材料。借助于高科技,我们预定一个装置或者产品,这些产品用相对复杂和熟练的原理运转或者起作用;这些例子包括电子设备( VCRs, CD 播放器,计算机,光纤系统,宇宙飞船,航天飞机和军事火箭。

These advanced materials are typically either traditional materials whose properties have been enhanced or newly developed, high-performance materials. Furthermore, they may be of all material types (e.g., metals, ceramics, polymers, and are normally relatively expensive.

译文:这些高级材料或是典型的传统材料,它们的性质被提高,最近开发出来的,高性能材料。除此之外,它们可能是所有材料类型(比如,金属、陶瓷和聚合物,通常相对较贵。

In subsequent chapters are discussed the properties and applications of a number of advanced materials—for example, materials that are used for lasers, integrated circuits, magnetic information storage, liquid crystal displays (LCDs,

fiber optics, and the thermal protection system for the Space Shuttle Orbiter. 译文:在下面的章节将讨论众多先进材料的性质和应用-比如被用作激光,集成电路,磁信息存储,液晶显示器,光纤和空间舱轨道的热保护系统的材料。

MODERN MATERIALS’ NEEDS

In spite of the tremendous progress that has been made in the discipline of materials science and engineering within the past few years, there still remain technological challenges, including the development of even more sophisticated and specialized materials, as well as consideration of the environmental impact of materials production. Some comment is appropriate relative to these issues so as to round out

this perspective.

译文:在过去几年内,不论材料科学与工程的规律取得了巨大的进步,仍然有一些技术挑战,包括开发更加熟练的专业化的材料,并且考虑材料生产对环境导致的影响。针对这个问题,一些评论是十分相关的。

Nuclear energy holds some promise, but the solutions to the many problems that remain will necessarily involve materials, from fuels to containment structures to facilities for the disposal of radioactive waste.

译文:核能还保持着一些承诺,但是解决许多仍然存在的问题,将有必要把材料包括在里,从燃料到保护结构以便方便处置这些放射性废料。

Significant quantities of energy are involved in transportation. Reducing the weight of transportation vehicles (automobiles, aircraft, trains, etc., as well as increasing engine operating temperatures, will enhance fuel efficiency. New high strength,low-density structural materials remain to be developed, as well as materials that have higher-temperature capabilities, for use in engine components.

译文:相当数量的能源用在交通上。减少交通工具(汽车,飞机,火车等的重量,和提高引擎操作温度,将提高燃料的使用效率。新的

高强,低密度结构材料仍在发展,用作引擎部位能耐高温材料也在发展中。

Furthermore, there is a recognized need to find new, economical sources of energy, and to use the present resources more efficiently. Materials will undoubtedly play a significant role in these developments.

译文:除此之外,寻找新的、经济的能源资源,并且更加有效的使用目前现存的资源是公认为必须的。材料将毫无疑问的在这些发展过程中扮演重要的角色。

For example, the direct conversion of solar into electrical energy has been demonstrated. Solar cells employ some rather complex and expensive materials. To

ensure a viable technology, materials that are highly efficient in this conversion process yet less costly must be developed.

译文:比如,太阳能直接转化为电能已经被证实了。太阳能电池使用相当复杂并且昂贵的材料。为了保证技术的可行,在这个转化过程中的高效但不贵的材料必须被发展。

Furthermore, environmental quality depends on our ability to control air and water pollution. Pollution control techniques employ various materials. In addition, materials processing and refinement methods need to be improved so that they produce less environmental degradation, that is, less pollution and less despoilage of the landscape from the mining of raw materials.

译文:除此之外,环境质量取决于我们控制大气和水污染的能力。污染控制技术使用了各种材料。再者,材料加工和精制的方法需要改善以便它们产生很少的环境退化,也就是说,在生材料加工过程中,带来更少的污染和更少的对自然环境的破坏。

Also, in some materials manufacturing processes, toxic substances are produced, and the ecological impact of their disposal must be considered. Many materials that we use are derived from resources that are nonrenewable, that is, not capable of being regenerated.

These include polymers, for which the prime raw material is oil, and some metals. These nonrenewable resources are gradually becoming depleted.

译文:也,在一些材料生产过程中,有毒物质产生了,并且它们的处置对生态产生的影响必须加以考虑。我们使用的许多材料来源于不可再生的资源,不可再生也就是说不能再次生成的。这些材料包括聚合物,最初的原生材料是油和一些金属。这些不可再生的资源逐渐变得枯竭

which necessitates: 1 the discovery of additional reserves, 2 the development of new materials having comparable properties with less adverse environmental impact, and/or 3 increased recycling efforts and the

development of new recycling technologies.

译文:下面是必须的:1发现另外的储藏,2开发拥有较少负环境影响的新材料,3增加循环的努力并且开发新的循环技术。

As a consequence of the economics of not only production but also environmental impact and ecological factors, it is becoming increasingly important to consider the

‘‘cradle-to-grave’’ li fe cycle of materials relative to the overall manufacturing process.

译文:结果,不仅是生产,而且环境影响和生态因子,和材料整个生产过程紧密相关的材料“一生”的生命周期的考虑变得越来越重要。

Unit3 Atomic Structure of Materials

1.众所周知所有的物质都是由原子组成的。在下面周期表中我们可

以知道仅仅大约有100多种不同种类的原子存在于整个宇宙中 ,从我们呼吸的空气,到各种各样性质迥异的金属成千上万的物种均是由一百多种原子组成的。金属与陶瓷有不同表现行为,陶瓷又与聚合物有所差异。物质的性能取决于组成他们的原子类型以及原子的结合方式。材料的结构可以根据我们所认为的各种特性的的数量级来分类,三种最常见的主要结构上的分类通常按尺寸的增大列出它们是,原子的结构是指不可见的结构例如原子间的结合方式以及原子的排布。微观结构是指不能同肉眼观察到而能用显微镜观察到的结构。宏观结构是指可以用肉眼直接观察到的结构。

2.原子结构主要影响物质的化学性质、物理性质、耐热性、电性、

磁性、光学性质。微观结构和宏观结构也能影响这些性质但它们通常在力学性质和化学反应速率方面的影响更大。材料的性能为材料的结构提供了一定的线索。

金属的具有的强度就说明构成他的原子是通过很强的成健能力结合在一起的.然而

由于金属经常成型,这些结合力必须允许原子运动。为了了解材料的结构,我们必须知道原子所呈现的类型,原子是如何排布的、如何结合的。

3.从基础化学我们知道任何元素的原子结构都是有被电子围绕的带

正电的原子核组成。一个元素的原子数目显示了原子核中带正电的质子数。为了确定在一个原子里有多少中子,只需要把原子的数目从原子的重量中减去。

4.原子具有平衡的电荷。因此,通常有和质子数目相同的带负电荷

的电子围绕在原子核周围。我们都知道电子以不同的能量存在,那些围绕在原

子核周围的电子可以方便的认为是一个能源层。例如。

镁原子序数是12 最内层有两个电子 8个电子,最外层有两个电子。所有的化学键都包含电子。如果原子共用一个或多个电子时他们会保持很紧密。当原子没有部分填充的电子层时,它们会处于最稳定的状态。如果一个原子在电子层上仅有几个

电子那么它就趋向于失去电子使电子层变空。这些即是金属元素。当金属原子结合, 金属键就出现了。

Unit10 Introduction to Ceramic Materials

The word "ceramic" is derived from the Greek keramos, which means "potter's clay" or "pottery." Its origin is a Sanskrit term meaning "to burn." So the early Greeks used "keramous" when describing products obtained by heating clay-containing materials. The term has long included all products made from fired clay, for example, bricks, fireclay refractories, sanitaryware, and tableware.

“陶瓷”这个词是来自希腊keramos,这意味着“陶土”或“陶”。它的起源是梵文术语,意思是“燃烧”。因此,早期的希腊人用“keramous”描述加热含粘土的物料获得的

产品。这个词早已包括所

有陶土制成的产品,例如,砖,粘土质耐火材料,卫生洁具,餐具。

In 1822, refractory silica were first made. Although they contained no clay, the traditional ceramic process of shaping, drying, and firing was used to make them. So the term" ceramic," while retaining its original sense of a product made from clay, began to include other products made by the same manufacturing process. The field of ceramics (broader than the materials themselves can be defined as the art and science of making and using solid articles that contain as their essential component a ceramic. This definition covers the purification of raw materials, the study and production of the chemical compounds concerned, their formation into components, and the study of structure, composition, and properties.

1822年,耐火材料二氧化硅被首次提出。虽然他们中没有粘土,传

统陶瓷的塑造过程,干燥和烧成使用,使它们。所以说,“陶瓷”,

同时保留其原来意义上的粘土制成的产品,开始向包括由同一制造工

艺制成的其他产品。陶瓷比材料本身更广泛的领域可以被定义为制作

和使用含有固体的文章作为自己的重要组成部分陶瓷艺术和科学。这

个定义涵盖了原料的净化,研究和生产有关的化学成分,他们到组件

的形成,结构,组成和性质的研究。

Ceramics are usually associated with "mixed" bonding-a combination of covalent, ionic, and sometimes metallic. They consist of arrays of interconnected atoms; there are no discrete molecules. This characteristic distinguishes ceramics from molecular solids such as iodine crystals (composed of discrete I2 molecules and paraffin wax (composed of long-chain alkane molecules. It also excludes ice, which is composed of discrete H20 molecules and often behaves just like many ceramics. The majority of ceramics are compounds of metals or metalloids and nonmetals. Most frequently they are oxides, nitrides, and carbides.

陶瓷通常与“混合”接合的共价键,离子,有时金属结合。他们组

成的相互联系的原子阵列;没有离散的分子。这一特点区分,如碘晶体(离散碘分子组成和石蜡(长链烷烃分子组成分子固体的陶瓷。

它也排除了冰,这是由离散的水分子,往往表现就像许多陶瓷。大多

数陶瓷,金属或非金属化合物和非金属。他们最常见的氧化物,氮化

物和碳化物。

However, diamond and graphite are also classified as ceramics. These forms of carbon are inorganic in the most basic meaning of the term: they were not prepared from the living organism.

然而,金刚石和石墨也被归类为陶瓷。这些形式的碳是无机一词的最基本的含义:他们不准备从活的有机体。

General Properties一般属性

Ceramics generally have specific properties associated with them. We will look at some properties and see how closely they match our expectations of what constitutes a ceramic.

陶瓷一般都与他们相关的特定属性。我们将看看一些属性,看看他们如何紧密匹配何谓陶瓷我们的期望。

Brittleness脆性This probably comes from personal experiences such as dropping a glass beaker or a dinner_ plate. The reason that the majority of ceramics are brittle is the mixed ionic-covalent bonding that holds the constituent atoms together. At high temperatures (above the glass transition temperature, glass no longer behaves in a brittle manner; it behaves as a viscous liquid. That is why it is easy to form glass into intricate

shapes. So what we can say is that most ceramics are brittle at room temperature but not necessarily at elevated temperatures.

这可能来自于个人的经验,如删除一个玻璃烧杯或餐盘。大多数陶瓷是易碎的原因是共同持有的组成原子的混合离子共价键。在高温(玻璃化转变温度以上,玻璃不再表现脆性的方式,它作为一种粘性液体的行为。这就是为什么它很容易形成复杂形状的玻璃。因此,我们可以说是大多数陶瓷在室温下很脆,但在高温下不一定。

Poor electrical and thermal conduction恶劣的电气和热传导The valence electrons are tied up in bonds, and are not free as they are in metals. In metals it is the free electrons-the electron gas-that determines many of their electrical and thermal properties. Diamond, which is classified as a ceramic, has the highest thermal conductivity of any known material. The conduction mechanism is due to Phonons, not electrons. Ceramics can also have high electrical conductivity,(1the oxide ceramic, ReO3, has an electrical conductivity at room temperature similar to that of Cu; (2 the mixed oxide YBa2Cu3O7 is an HTSC; it has zero resistivity below 92K.

价电子被捆绑起来的债券,是不是免费的,因为他们在金属。在金属,它是自由电子的电子气,决定其电气和热性能。钻石,这是作为陶瓷的分类,有任何已知的材料的导热系数最高。传导机制是由于声子,没有电子。陶瓷也可以有高导电性,(1氧化物陶瓷,ReO3,有一个类似的铜在室温下的电导率;(2混合氧化物YBa2Cu3O7是高温超导;它具有零电阻低于92K。

These are two examples that contradict the conventional wisdom when it comes to ceramics. 这些都违背了传统的智慧，当谈到陶瓷的两个例子。 Compressive strength 抗压强度 Ceramics are stronger in compression than in tension, whereas metals have comparable tensile and compressive strengths. This difference is important when we use ceramic components for load-bearing applications. It is necessary to consider the stress distributions in the ceramic to ensure that they are compressive. An important example is in the design of concrete bridges-the concrete, a CMC, must be kept in compression.

Ceramics generally have low toughness, although combining them in composites can dramatically improve this property. 陶瓷在紧张的压缩比，而金属具有可比性的抗拉和抗压强度。这种差异是很重要的，当我们使用承载应用的陶瓷元件。这是有必要考虑在陶瓷的应力分布，以确保它们是压缩。一个重要的例子是在设计的混凝土桥梁，混凝土，中央军委，必须保持在压缩。陶瓷一般有韧性低，虽然复合材料相结合，可以极大地提高这个属性。 Chemical insensitivity 化学不灵敏度 A large number of ceramics are stable in both harsh chemical and thermal environments. Pyrex glass is used widely in chemistry laboratories specifically be-cause it is resistant to many corrosive chemicals, stable at high temperatures (it does not soften until 1100K, and is resistant to thermal shock because of its low coefficient of thermal expansion (33×10-7K-1. It is also widely used in bakeware. 大量的陶瓷，在苛刻的化学和热环境是稳定的。硼硅玻璃是在化学实验室中广泛使用，具体原因是抵抗许多腐蚀性化学品的，稳定的高温（不软化，直到1100K），抵抗热冲击，由于其低的热膨胀系数（33×10- 7K- 1）。它也被广泛用于在烤盘。 Transparent透明 Many ceramics are transparent because they have a large Eg. Examples include sapphire watch covers, precious stones, and optical fibers. Glass optical fibers have a percent

transmission >96%km-1. Metals are transparent to visible light only when they are very thin, typically less than 0.1μm. 许多陶瓷是透明的，因为他们有一个大的如。例子包括蓝宝石手表盖，宝石，和光纤。玻璃光纤具有传输％>96％每公里。金属可见光是透明的的，只有当他们是非常薄，通常小于0.1微米。 Although it is always possible to find at least one ceramic that shows a typical behavior, the properties mentioned above are in many cases different from those shown by metals and polymers. 虽然它总是可以找到至少一个陶瓷，显示了一个典型的行为，上面提到的属性不同的金属和聚合物中的许多案件。

Types of Ceramic and Their Applications陶瓷及其应用的类型 Large numbers of materials are ceramics. The applications for these materials are diverse, from bricks and tiles to electronic and magnetic components. These applications use the wide range of properties exhibited by ceramics. Some of these properties are listed in Table 3.1 together

with examples of specific ceramics and applications. The functions of ceramic products are dependent on their chemical composition and microstructure, which determines their properties. It is the interrelationship between structure and properties that is a key element of materials science and engineering. 大量的材料是陶瓷。这些材料的应用是多种多样的，从砖瓦，电子和磁性元件。这些应用程序使用广泛的陶瓷展出的属性。这些属性与特定的陶瓷和应用的例子，在表3.1列出了一些。陶瓷产品的功能上取决于其化学成分和微观结构，这就决定了它们的属性。它的结构和性能的关键因素是材料科学与工程之间的相互关系。 You may find that, in addition to dividing ceramics according to their properties and applications, it is common to class them as traditional or advanced. Traditional ceramics include high-volume items such bricks and tiles, toilet bowls (whitewares, and pottery. Advanced ceramics include newer materials such as laser host materials, piezoelectric ceramics .ceramics for dynamic random access memories (DRAMs, and so on, often produced in small quantities with higher prices. There are other characteristics that separate these categories. 您可能会发现，除了除以陶瓷根据其性质和应用，它是常见他们为传统或先进的阶级。传统的陶瓷，包括高容量的项目，如砖瓦，马桶（whitewares），和陶器。先进陶瓷新材料，如激光基质材料，压电陶瓷，陶瓷，动态随机存取存储器（DRAM的）等，往往在价格较高的小批量的生产。有单独的这些类别的其他特点。 Traditional ceramics are usually based on clay and silica. There is sometimes a tendency to equate traditional ceramics with low technology, however, advanced manufacturing techniques are often used. Competition among producers has caused processing to becom1 more efficient and cost effective. Complex tooling and machinery is often used and may be coupled with computer-assisted process control. 通常是基于传统的陶瓷粘土和二氧化硅。然而，

有时也有一种倾向等同于低技术传统陶瓷，先进的制造技术通常用于。生产者之间的竞争已经引起处理becom1更有效率和成本效益。经常使用复杂的工具和机械，并可能与计算机辅助工艺控制。 Advanced ceramics are also referred to as "special", “technical", or“engineering" ceramics. They exhibit superior mechanical

properties, corrosion/oxidation resistance, or electrical, optical, and/or magnetic properties. While traditional clay-based ceramics have been used for over

25000 years, advanced ceramics have generally been developed within the last 100 years. 先进陶瓷也被称为“特殊”，“科技”，或“工程”的陶瓷。他们表现出优越的机械性能，耐腐蚀/抗氧化性能，电，光，和/或磁学性质。虽然已超过25000年的使用传统的粘土基陶瓷，先进陶瓷已普遍被发达国家在过去100年。 Table 3.2 compares traditional and advanced ceramics in terms of the type of raw materials used, the forming and shaping processes, and the methods used for characterization. 表3.2比较传统和先进的陶瓷，在原材料的使用类型方面的形成和塑造的过程和方法用于表征。

城市学院英语课文翻译word版本

城市学院英语课文翻 译

Don't Wait Until Death Does Its Part We have but one body. It must last a lifetime. Without it, life ends, and we are done and finished. But do we treat our body fairly, lovingly, like prized possessions? Do we appreciate our body's nonstop efforts to function smoothly? My body asks for little: water to keep hydrated; food for nutrients, energy, and strong bones; rest when I'm tired or sick; and play to lift my spirits. Its ability to self-repair and respond to good care is incredible. But until recently, I have abused my body with excesses of all kinds. Not only did I take its resiliency for granted, I was annoyed when a physical problem, such as a cold or injury, kept me from doing what I want. Moreover, I was harshly critical when it failed to conform to standards of beauty in the media. My overeating, lazy lifestyle, and excessive work had a negative impact on my life, though not fatal. I've also seen friends and family members destroy their body through drugs, alcoholism, or workaholism. For years I had good intentions to change, but I didn't follow through. I could see my future: increased medical expenses, exhausted senses, premature death. Once I understand that it is in my own self-interest to take care of it, I'm struggling to develop a positive relationship with my body. Evidently, I'm not the only one with this awareness now. I begin to make more constructive choices. Instead of asking the question, “What do I want?” I ask, “What does my body need?” And then I respond acc ordingly. Positive actions — exercising, eating mindfully, getting enough rest and water, limiting my work hours, and scheduling recreation — have gradually become regular habits rather than disciplined efforts. After all, each of us gets only one body. So don't wait until death does its part. Appreciate our body and treat it lovingly. It will reward us with a longer, healthier and happier life.

化学专业英语(修订版)翻译

01 THE ELEMENTS AND THE PERIODIC TABLE 01 元素和元素周期表 The number of protons in the nucleus of an atom is referred to as the atomic number, or proton number, Z. The number of electrons in an electrically neutral atom is also equal to the atomic number, Z. The total mass of an atom is determined very nearly by the total number of protons and neutrons in its nucleus. This total is called the mass number, A. The number of neutrons in an atom, the neutron number, is given by the quantity A-Z. 质子的数量在一个原子的核被称为原子序数,或质子数、周淑金、电子的数量在一个电中性原子也等于原子序数松山机场的总质量的原子做出很近的总数的质子和中子在它的核心。这个总数被称为大量胡逸舟、中子的数量在一个原子,中子数,给出了a - z的数量。 The term element refers to, a pure substance with atoms all of a single kind. T o the chemist the "kind" of atom is specified by its atomic number, since this is the property that determines its chemical behavior. At present all the atoms from Z = 1 to Z = 107 are known; there are 107 chemical elements. Each chemical element has been given a name and a distinctive symbol. For most elements the symbol is simply the abbreviated form of the English name consisting of one or two letters, for example: 这个术语是指元素,一个纯物质与原子组成一个单一的善良。在药房“客气”原子的原子数来确定它,因为它的性质是决定其化学行为。目前所有原子和Z = 1 a到Z = 107是知道的;有107种化学元素。每一种化学元素起了一个名字和独特的象征。对于大多数元素都仅仅是一个象征的英文名称缩写形式,一个或两个字母组成,例如: oxygen==O nitrogen == N neon==Ne magnesium == Mg

汽车专业英语翻译综合

第一章汽车总论 1)Today’s average car contains more than 15,000 separate, individual parts that must work together. These parts can be grouped into four major categories: body, engine, chassis and electrical equipment 。P1 现在的车辆一般都由15000多个分散、独立且相互配合的零部件组成。这些零部件主要分为四类：车身、发动机、底盘和电气设备。 2)The engine acts as the power unit. The internal combustion engine is most common: this obtains its power by burning a liquid fuel inside the engine cylinder. There are two types of engine: gasoline (also called a spark-ignition engine) and diesel (also called a compression-ignition engine). Both engines are called heat engines; the burning fuel generates heat which causes the gas inside the cylinder to increase its pressure and supply power to rotate a shaft connected to the power train. P3 发动机作为动力设备，常见的类型是内燃机，其原理是通过发动机缸内的液体燃料燃烧而产生能量。发动机可分为两类：汽油机（点燃式）和柴油机（压燃式），都属于热力发动机。燃料燃烧产生热量使缸内气压上升，产生的能量驱动轴旋转，并传递给动力传动系。 第二章内燃机 1)Power train system: conveys the drive to the wheels 2)Steering system: controls the direction of movement 3)Suspension system: absorbs the road shocks 4)Braking system: slows down the vehicle P4 传动系把发动机输出的扭矩传递给驱动轮。传动系包括离合器（对应机械变速器）或液力变矩器（对应液力自动变速器）、变速器、驱动轴、主减速器、差速器和驱动桥。 5)Drum brakes have a drum attached to the wheel hub, and braking occurs by means of brake shoes expanding against the inside of the drum. With disc brakes, a disc attached to the wheel hub is clenched between two brake pads. P6 鼓式制动器的制动鼓和轮毂连接，制动蹄张开压紧制动鼓内侧从而产生制动。在盘式制动器上，连着轮毂的制动盘被紧紧夹在两个制动块之间。 1)Linking the piston by a connecting rod to a crankshaft causes the gas to rotate the shaft through half a turn.The power stroke"uses up"the gas,so means must be provided to expel the burnt gas and recharge the cylinder with a fresh petrol-air mixture:this control of gas movement is the duty of the valves;An inlet valve allows the mixture to enter at the right time and an exhaust valve lets out the burnt gas after the gas has done its job . P10 活塞通过连杆和曲轴连接，使得气体带动曲轴旋转半圈。作功冲程耗尽了所有的气体，这样就必须采取相应的措施排出废气并且向气缸内充入新的可燃混合气：气体的运动由气门来控制。进气门使可燃混合气在恰当的时刻进入气缸，排气门使燃烧后的废气排出气缸。 2)The spark-ignition engine is an internal-combustion engine with externally supplied in ignition,which converts the energy cntained in the fuel to kinetic energy.The cycle of operations is spread over four piston strokes. To complete the full cycle it takes two revolutions of the crankshaft. P11 火花点火式发动机是由外部提供点火的内燃机，从而将含在燃料内的能量转化成动能。发动机的一个工作循环分布在活塞的四个行程中，一个完整的工作循环曲轴需要转动两圈。 3)The oil pump in the lubricating system draws oil from the oil pan and sends it to all working parts in the engine. The oil drains off and runs down into the pan. Thus,there is constant circulation of oil between the pan and the working parts of the engine. P15

《机械工程专业英语教程》课文翻译

Lesson 1 力学的基本概念 1、词汇： statics [st?tiks] 静力学；dynamics动力学；constraint约束；magnetic [m?ɡ＇netik]有磁性的；external [eks＇t?:nl] 外面的, 外部的；meshing啮合；follower从动件；magnitude [＇m?ɡnitju:d] 大小；intensity强度，应力；non-coincident [k?u＇insid?nt]不重合；parallel [＇p?r?lel]平行；intuitive 直观的；substance物质；proportional [pr?＇p?:??n?l]比例的；resist抵抗，对抗；celestial [si＇lestj?l]天空的；product乘积；particle质点；elastic [i＇l?stik]弹性；deformed变形的；strain拉力；uniform全都相同的；velocity[vi＇l?siti]速度；scalar[＇skeil?]标量；vector[＇vekt?]矢量；displacement代替；momentum [m?u＇ment?m]动量； 2、词组 make up of由……组成；if not要不，不然；even through即使，纵然； Lesson 2 力和力的作用效果 1、词汇： machine 机器；mechanism机构；movable活动的；given 规定的，给定的，已知的；perform执行；application 施用；produce引起，导致；stress压力；applied施加的；individual单独的；muscular [＇m?skjul?]]力臂；gravity[ɡr?vti]重力；stretch伸展，拉紧，延伸；tensile[tensail]拉力；tension张力，拉力；squeeze挤；compressive 有压力的，压缩的；torsional扭转的；torque转矩；twist扭，转动；molecule [m likju:l]分子的；slide滑动; 滑行；slip滑，溜；one another 互相；shear剪切；independently独立地，自立地；beam梁；compress压；revolve (使)旋转；exert [iɡ＇z?:t]用力，尽力，运用，发挥，施加；principle原则, 原理，准则，规范；spin使…旋转；screw螺丝钉；thread螺纹； 2、词组 a number of 许多；deal with 涉及，处理；result from由什么引起；prevent from阻止，防止；tends to 朝某个方向；in combination结合；fly apart飞散； 3、译文： 任何机器或机构的研究表明每一种机构都是由许多可动的零件组成。这些零件从规定的运动转变到期望的运动。另一方面，这些机器完成工作。当由施力引起的运动时，机器就开始工作了。所以，力和机器的研究涉及在一个物体上的力和力的作用效果。 力是推力或者拉力。力的作用效果要么是改变物体的形状或者运动，要么阻止其他的力发生改变。每一种

outofstep课文全文翻译.doc

Unit 3 Out of Step Bill Bryson 1 After living in England for 20 years, my wife and I decided to move back to the United States. We wanted to live in a town small enough that we could walk to the business district, and settled on Hanover, N.H., a typical New England town—pleasant, sedate and compact. It has a broad central green surrounded by the venerable buildings of Dartmouth College, an old-fashioned Main Street and leafy residential neighborhoods. 2 It is, in short, an agreeable, easy place to go about one’ s business on foot, and ye far as I can tell, virtually no one does. 3 Nearly every day, I walk to the post office or library or bookstore, and sometimes, if I am feeling particu larly debonair, I stop at Rosey Jekes Caféa cappuccino. Occasionally, in the evenings, my wife and I stroll up to the Nugget Theatre for a movie or to Murphy’ s on the Green for a beer, I wouldn’ t dream of going to any of these places by car. People ha ve gotten used to my eccentric behavior, but in the early days acquaintances would often pull up to the curb and ask if I wanted a ride. 4“ I’ m going your way,” they would insist when I politely declined. no bother.”

《化学工程与工艺专业英语》课文翻译 完整版

Unit 1 Chemical Industry 化学工业 1.Origins of the Chemical Industry Although the use of chemicals dates back to the ancient civilizations, the evolution of what we know as the modern chemical industry started much more recently. It may be considered to have begun during the Industrial Revolution, about 1800, and developed to provide chemicals roe use by other industries. Examples are alkali for soapmaking, bleaching powder for cotton, and silica and sodium carbonate for glassmaking. It will be noted that these are all inorganic chemicals. The organic chemicals industry started in the 1860s with the exploitation of William Henry Perkin‘s discovery if the first synthetic dyestuff—mauve. At the start of the twentieth century the emphasis on research on the applied aspects of chemistry in Germany had paid off handsomely, and by 1914 had resulted in the German chemical industry having 75% of the world market in chemicals. This was based on the discovery of new dyestuffs plus the development of both the contact process for sulphuric acid and the Haber process for ammonia. The later required a major technological breakthrough that of being able to carry out chemical reactions under conditions of very high pressure for the first time. The experience gained with this was to stand Germany in good stead, particularly with the rapidly increased demand for nitrogen-based compounds (ammonium salts for fertilizers and nitric acid for explosives manufacture) with the outbreak of world warⅠin 1914. This initiated profound changes which continued during the inter-war years (1918-1939). 1．化学工业的起源 尽管化学品的使用可以追溯到古代文明时代，我们所谓的现代化学工业的发展却是非常近代（才开始的）。可以认为它起源于工业革命其间，大约在1800年，并发展成为为其它工业部门提供化学原料的产业。比如制肥皂所用的碱，棉布生产所用的漂白粉，玻璃制造业所用的硅及Na2CO3. 我们会注意到所有这些都是无机物。有机化学工业的开始是在十九世纪六十年代以William Henry Perkin 发现第一种合成染料—苯胺紫并加以开发利用为标志的。20世纪初，德国花费大量资金用于实用化学方面的重点研究，到1914年，德国的化学工业在世界化学产品市场上占有75%的份额。这要归因于新染料的发现以及硫酸的接触法生产和氨的哈伯生产工艺的发展。而后者需要较大的技术突破使得化学反应第一次可以在非常高的压力条件下进行。这方面所取得的成绩对德国很有帮助。特别是由于1914年第一次世界大仗的爆发，对以氮为基础的化合物的需求飞速增长。这种深刻的改变一直持续到战后（1918-1939）。 date bake to/from: 回溯到 dated: 过时的，陈旧的 stand sb. in good stead: 对。。。很有帮助

机械工程专业英语 翻译

2、应力和应变 在任何工程结构中独立的部件或构件将承受来自于部件的使用状况或工作的外部环境的外力作用。如果组件就处于平衡状态,由此而来的各种外力将会为零,但尽管如此,它们共同作用部件的载荷易于使部件变形同时在材料里面产生相应的内力。 有很多不同负载可以应用于构件的方式。负荷根据相应时间的不同可分为: (a)静态负荷是一种在相对较短的时间内逐步达到平衡的应用载荷。 (b)持续负载是一种在很长一段时间为一个常数的载荷, 例如结构的重量。这种类型的载荷以相同的方式作为一个静态负荷; 然而,对一些材料与温度和压力的条件下,短时间的载荷和长时间的载荷抵抗失效的能力可能是不同的。 (c)冲击载荷是一种快速载荷(一种能量载荷)。振动通常导致一个冲击载荷, 一般平衡是不能建立的直到通过自然的阻尼力的作用使振动停止的时候。 (d)重复载荷是一种被应用和去除千万次的载荷。 (e)疲劳载荷或交变载荷是一种大小和设计随时间不断变化的载荷。 上面已经提到，作用于物体的外力与在材料里面产生的相应内力平衡。因此,如果一个杆受到一个均匀的拉伸和压缩，也就是说, 一个力,均匀分布于一截面,那么产生的内力也均匀分布并且可以说杆是受到一个均匀的正常应力,应力被定义为 应力==负载 P /压力 A, 因此根据载荷的性质应力是可以压缩或拉伸的,并被度量为牛顿每平方米或它的倍数。 如果一个杆受到轴向载荷，即是应力，那么杆的长度会改变。如果杆的初始长度L和改变量△L已知，产生的应力定义如下: 应力==改变长△L /初始长 L 因此应力是一个测量材料变形和无量纲的物理量 ,即它没有单位;它只是两个相同单位的物理量的比值。 一般来说,在实践中,在荷载作用下材料的延伸是非常小的, 测量的应力以*10-6的形式是方便的, 即微应变, 使用的符号也相应成为ue。 从某种意义上说，拉伸应力与应变被认为是正的。压缩应力与应变被认为是负的。因此负应力使长度减小。 当负载移除时，如果材料回复到初始的，无负载时的尺寸时，我们就说它是具有弹性的。一特定形式的适用于大范围的工程材料至少工程材料受载荷的大部分的弹性, 产生正比于负载的变形。由于载荷正比于载荷所产生的压力并且变形正比于应变, 这也说明,当材料是弹性的时候, 应力与应变成正比。因此胡克定律陈述, 应力正比于应变。 这定律服从于大部分铁合金在特定的范围内, 甚至以其合理的准确性可以假定适用于其他工程材料比如混凝土，木材，非铁合金。 当一个材料是弹性的时候，当载荷消除之后，任何负载所产生的变形可以完全恢复,没有永久的变形。

全新版大学英语[第二版]综合教程2课文翻译

Unit 1 Text A Howard Gardner, a professor of education at Harvard University, reflects on a visit to China and gives his thoughts on different approaches to learning in China and the West. 哈佛大学教育学教授霍华德·加德纳回忆其中国之行，阐述他对中西方不同的学习方式的看法。 Learning, Chinese-Style Howard Gardner 1 For a month in the spring of 1987, my wife Ellen and I lived in the bustling eastern Chinese city of Nanjing with our 18-month-old son Benjamin while studying arts education in Chinese kindergartens and elementary schools. But one of the most telling lessons Ellen and I got in the difference between Chinese and American ideas of education came not in the classroom but in the lobby of the Jinling Hotel where we stayed in Nanjing. 中国式的学习风格 霍华德·加德纳 1987年春，我和妻子埃伦带着我们18个月的儿子本杰明在繁忙的中国东部城市南京住了一个月，同时考察中国幼儿园和小学的艺术教育情况。然而，我和埃伦获得的有关中美教育观念差异的最难忘的体验并非来自课堂，而是来自我们在南京期间寓居的金陵饭店的大堂。 2 The key to our room was attached to a large plastic block with the room number on it. When leaving the hotel, a guest was encouraged to turn in the key, either by handing it to an attendant or by dropping it through a slot into a box. Because the key slot was narrow, the key had to be positioned carefully to fit into it. 我们的房门钥匙系在一块标有房间号的大塑料板上。酒店鼓励客人外出时留下钥匙，可以交给服务员，也可以从一个槽口塞入钥匙箱。由于口子狭小，你得留神将钥匙放准位置才塞得进去。 3 Benjamin loved to carry the key around, shaking it vigorously. He also liked to try to place it into the slot. Because of his tender age and incomplete understanding of the need to position the key just so, he would usually fail. Benjamin was not bothered in the least. He probably got as much pleasure out of the sounds the key made as he did those few times when the key actually found its way into the slot. 本杰明爱拿着钥匙走来走去，边走边用力摇晃着。他还喜欢试着把钥匙往槽口里塞。由于他还年幼，不太明白得把钥匙放准位置才成，因此总塞不进去。本杰明一点也不在意。他从钥匙声响中得到的乐趣大概跟他偶尔把钥匙成功地塞进槽口而获得的乐趣一样多。 4 Now both Ellen and I were perfectly happy to allow Benjamin to bang the key

汽车专业英语翻译

About car engine Of all automobile components,an automobile engie is the most complicated assembly with dominant effects on the function of an autombile.So, the engine is generally called the"heat"of an automobile. 在汽车的所有部件中，汽车发动机是最复杂的组件，其对整车性能有着决定性的作用。因而发动机往往被称作发动机的“心脏”。 There are actually various types of engines such as electric motors,stream engines,andinternal combustion engines.The internal combustion engines seem to have almost complete dominance of the automotive field.The internal combustion engine,as its name indicates,burns fuel within the cylinders and converts the expanding force of the combustion into rotary force used to propel the vehicle. 事实上，按动力来源分发动机有很多种，如电动机、蒸汽机、外燃机等。然而内燃机似乎在发动机领域有着绝对的统治地位。就像其字面意思一样，内燃机的染料在气缸内燃烧，通过将燃烧产生气体的膨胀力转换成转动力来驱动发动机前进。 Engine is the power source of the automobile.Power is produced by the linear motion of a piston in a cylinder.However,this linear motion must be changed into rotary motion to turn the wheels of cars or trucks.The puston attached to the top of a connecting rod by a pin,called a piston pin or wrist pin.The bottom of the connecting rod is attached to the crankshaft.The connecting rod transmits the up-and-down motion of the piston to the crankshaft,which changes it into rotary motion.The connecting rod is mounted on the crankshaft with large bearings called rod bearing.Similar bearings, called main bearings,are used to mount the crankshaft in the block. 发动机是整部车的动力来源。能量来自于活塞在气缸内的（往复）直线运动。然而这种（往复）直线运动必须要转换成旋转运动才能驱动车轮。活塞与连杆通过一个销来连接，这个销称为活塞销。连杆的下部连接于曲拐。连杆把活塞的上下往复运动传递给曲拐，从而将往复直线运动转变成旋转运动。连杆和曲拐的连接使用大的轴承，称之为连杆轴承，类似的轴承也用于将曲轴连接到机体，称之为主轴承。 They are generally two different types of cooling system:water-cooling system and air-cooling system.Water-cooling system is more common.The cooling medium, or coolant, in them is either water or some low-freezing liquid, called antifreeze.A water-cooling system consists of the engine water jacket, thermostat, water pump, radiator, radiator cap, fan, fan drive belt and neccessary hoses. 主要有两种类型的冷却系统：水冷和风冷。水冷系统更为普遍。系统所用冷却介质或是冷却液常委水或其他低凝固点液体，称为抗凝剂。一个完整的水冷系统包括机体水套，节温器，水泵，散热器，散热器罩，风扇，风扇驱动皮带和必需的水管。 A water-cooling system means that water is used as a cooling agent to circulate through the engine to absorb the heat and carry it to the radiator for disposal.The ebgine is cooled mainly through heat transfer and heat dissipation.The heat generated by the mixture burned in the engine must be transferred from the iron or aluminum cylinder to the waterin the water jacket.The outside of the water jacket dissipates some of the heat to the air surrounding it, but most of the heat is carried by the cooling water to the radiator for dissipation.When the coolant temperature in the system reaches 90°,the termostat valve open fully, its slanted edge shutting off

机械制造专业英语文章

机械制造专业英语文章 篇一：机械专业英语文章中英文对照 Types of Materials 材料的类型 Materials may be grouped in several ways. Scientists often classify materials by their state: solid, liquid, or gas. They also separate them into organic (once living) and inorganic (never living) materials. 材料可以按多种方法分类。科学家常根据状态将材料分为：固体、液体或气体。他们也把材料分为有机材料(曾经有生命的)和无机材料(从未有生命的)。 For industrial purposes, materials are divided into engineering materials or nonengineering materials. Engineering materials are those used in manufacture and become parts of products. 就工业效用而言，材料被分为工程材料和非工程材料。那些用于加工制造并成为产品组成部分的就是工程材料。 Nonengineering materials are the chemicals, fuels, lubricants, and other materials used in the manufacturing process, which do not become part of the product. 非工程材料则是化学品、燃料、润滑剂以及其它用于加工制造过程但不成为产品组成部分的材料。 Engineering materials may be further subdivided into: ①Metal ②Ceramics ③Composite ④Polymers, etc. 工程材料还能进一步细分为：①金属材料②陶瓷材料③复合材料④聚合材料，等等。 Metals and Metal Alloys 金属和金属合金 Metals are elements that generally have good electrical and thermal conductivity. Many metals have high strength, high stiffness, and have good ductility. 金属就是通常具有良好导电性和导热性的元素。许多金属具有高强度、高硬度以及良好的延展性。 Some metals, such as iron, cobalt and nickel, are magnetic. At low temperatures, some metals and intermetallic compounds become superconductors. 某些金属能被磁化，例如铁、钴和镍。在极低的温度下，某些金属和金属化合物能转变成超导体。 What is the difference between an alloy and a pure metal? Pure metals are elements which come from a particular area of the periodic table. Examples of pure metals include copper in electrical wires and aluminum in cooking foil and beverage cans. 合金与纯金属的区别是什么？纯金属是在元素周期表中占据特定位置的元素。 例如电线中的铜和制造烹饪箔及饮料罐的铝。 Alloys contain more than one metallic element. Their properties can be changed by changing the elements present in the alloy. Examples of metal alloys include stainless steel which is an alloy of iron, nickel, and chromium; and gold jewelry which usually contains an alloy of gold