机械工程专业英语.ppt

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1、 机械工程机械工程 专业英语专业英语课程介绍v学习专业英语的重要性v学习目的v为何在大三开设这门课程v专业英语的英文名称 “专业英语”-English for Special Purpose Specified English for.“机械工程专业英语”Specified English for Mechanical Engineeringv专业英语和普通英语的区别 一.词义特点 1.根据词类辨明词义 e.g:(1)Round(adj.)surface reflector is a key unit for the solar energy device.曲面反射器是太阳能装置的关键元件。(

2、2)This is the whole round(n.)of knowledge.这是全部知识范围。2.区分场合确定词义（不同的场合，词义也不一样。要根据 上下文和语言环境来确定词义）e.g:(1)pig:猪 iron 生铁 (机械专业)metal 金属锭 copper 生铜 (2)dog:狗 (机械专业)鸡心夹头,挡块 3.按照习惯搭配词义 e.g:(1)I have a short memory.(2)This biscuit eats short.(3)Indeed he has a short temper.4.联系上下文活用词义 e.g:(1)There is no physica

3、l contact between tool and workpiece.工具和工件之间没有有形（直接）的接触。(2)High-speed grinding does not know this disadvantage 高速磨削不知道（存在）这个缺点。二.句子结构特点 1.句子长 2.被动语态多 e.g:The rate at which work is done is called power.3.后置定语多 4.名词化结构多 e.g:to control the machine-the control of the machine v学习方法与教学方法v工具书的介绍 1.收词不足,收词量

4、有限 2.收词面广 3.例证丰富 4.释义地道,全面 5.词的用法说明较详细Lesson 1 Introduction for Materials vDesigners and engineers are usually more interested in the behavior of materials under load or when in a magnetic field than in why they behave as they do.1.are.more interested in.than in 对.比对.更兴趣 2.under load：承载时vYet the bet

5、ter one understands the nature of materials and the reasons for their physical and mechanical properties the more quickly and wisely will he/she be able to choose the proper material for a given design.1.the better.the more quickly and wisely:越.越.2.a given design:某个设计 vGenerally,a material property

6、is the measured magnitude of its response to a standard test performed according to a standard procedure in a given environment.1.the measured magnitude:测定的大小 2.response to:对.的反应vIn engineering materials the properties are recorded in handbooks or,for new materials,are made available by the supplier

7、.make sth.+形容词(sth.be make=形容词):使.怎么样 the properties are made available:使可获得vFrequently such information is tabulated for room-temperature conditions only,so when the actual service conditions are at subfreezing or elevated temperatures,more information is needed.1.room-temperature conditions:室温状态 2

8、.the actual service conditions：实际工作状态 3.elevated temperatures：高温vThe properties of materials are sometimes referred to as structure sensitive,as compared to structure-insensitive properties.1.be referred to as,be known as:称为 2.(as)compared to(with):与相比,同.比较起来,与相对应 3.structure sensitive,structure-ins

9、ensitive properties 结构敏感性,结构不敏感性vIn this case structure-insensitive properties include the traditional physical properties:electrical and thermal conductivity,specific heat,density,and magnetic and optical properties.electrical and thermal conductivity:导热性与导电性 specific heat:比热 specific weight:比重vThe

10、 structure-sensitive properties include the tensile and yield strength,hardness,and impact,creep,and fatigue resistance.1.the tensile(strength)and yield strength:拉伸强度和屈服强度 2.impact,creep,and fatigue resistance:抗冲击性,抗蠕性,抗疲劳性vIt is recognized that some sources maintain that hardness is not a true mech

11、anical property,because it varies somewhat with the characteristics of the indenter and therefore is a technological test.It is recognized that.认出,识别,考虑(认识)到 some sources maintain:一些资料(文件)v It is well known that other mechanical properties vary significantly with rate of loading,temperature,geometry

12、 of notch in impact testing,and the size and geometry of the test specimen.1.rate of loading:载荷大小 2.geometry of notch in impact testing:试验中缺口的几何形状vFurthermore,since reported test values of material properties are statistical averages,a commercial material frequently has a tolerance band of 5 percent

13、 or more deviation from a given published value.1.reported test values:所报道的测量值 2.statistical averages:统计平均值 mercial material:商用材料 4.tolerance band:公差带 5.deviation from:与.的偏差 6.a given published value:某个公布的值vThe properties of materials are sometimes referred to as structure sensitive,as compared to s

14、tructure-insensitive properties.be referred to as:指的是.;叫做;be known as:称为;叫做vIn this case structure-insensitive properties include the traditional physical properties:electrical and thermal conductivity,specific heat,density,and magnetic and optical properties.1.electrical and thermal conductivity:导热

15、性与导电性 2.specific heat:比热 specific weight:比重 The structure-sensitive properties include the tensile and yield strength,hardness,and impact,creep,and fatigue resistance.1.tensile and yield strength tensile(strength)and yield strength 2.impact,creep,and fatigue resistance impact(resistance),creep (resi

16、stance),and fatigue resistance 抗冲击性,抗蠕变性和抗疲劳性 It is recognized that some sources maintain that hardness is not a true mechanical property,because it varies somewhat with the characteristics of the indenter and therefore is a technological test.1.It is recognized that.It is known that.It is said that

17、.2.vary withvFurthermore,since reported test values of material properties are statistical averages,a commercial material frequently has a tolerance band of 5 percent or more deviation from a given published value.has a tolerance band of 5 percent or more deviation from vAny particular material can

18、be described by its behavior when subjected to external conditions.described by behavior when(any particular material )subjected to external condition(外力作用)vThus,when it is loaded under known conditions of direction,magnitude,rate,and environment,the resulting responses are called mechanical propert

19、ies.When it is loaded under known conditions of direction,magnitude,rate,and environment.vMechanical properties such as yield strength,impact strength,hardness,creep and fatigue resistance are strongly structure-sensitive,i.e.,they depend upon the arrangement of the atoms in the crystal lattice and

20、on any imperfections in that arrangement,whereas the physical properties are less structure-sensitive.arrangement of the atoms:原子排列vThese include electrical,thermal,magnetic,and opticalproperties and do depend in part upon structure;for example,the resistivity of a metal increases with the amount of

21、 coldwork.1.in part:部分2.increases with:随着.而提高3.cold work:冷作;冷成型,冷加工vPhysical properties depend primarily upon the relativeexcess or deficiency of the electrons that establish structuralbonds and upon their availability and mobility.1.excess or deficiency:超过或不足2.structural bonds:结构键vBetween the condu

22、ctors with high electron mobility and the insulators with no free electrons,precise control of the atomic architecture has created semiconductors that can have a planned modification of their electron mobility.1.high electron mobility:高电子迁移率 2.the conductors with high electron mobility:高电子迁移率的导体 3.t

23、he insulators with no free electrons:无自由电子的绝缘体 4.semiconductors that can have a planned modification of their electron mobility 有计划改变电子迁移的半导体vSimilarly,advances in solid-state optics have led to the development of the stimulated emission of electromagnetic energy in the microwave spectrum(masers)and

24、 in the visible spectrum(lasers).1.solid-state optics:固态光学器件 2.the stimulated emission:激射vIn studying the general structure of materials,one may consider three groupings;first,atomic structure,electronic configuration,bonding forces,and the arrangement of the aggregations of atoms;second,the physica

25、l aspect of materials,including properties such as electrical and thermal conductivity,specific heat,and magnetism;and third,their macroscopic properties,such as their mechanical behavior under load,which can be explained in terms of impurities and imperfections in the lattice structure and the proc

26、edures used to modify that behavior.1.bonding forces:结合力 2.aggregations of atoms:原子团 3.in terms of:用.语言来.专业英语的特点专业英语的特点v专业英语（specified English）是在自然科学和工程技术的专业领域中使用的一种英语文体。它是在专业技术的不断发展中逐渐形成并与专业技术同步发展的。由于专业技术的要求语言表述能客观、严谨地反映科学研究的内容，所以，专业英语的特点，除了包含一些实验数据、公式推导和数学符号以外，在词汇含义、语法结构、句型使用和修辞手法等方面与日常英语、文学英语有不同的

27、特点。这诚如著名科学家钱三强指出的：专业英语“无论在语法结构或词汇方面都逐渐形成它特有的习惯用法、特点与规律”。不学习和掌握这些特点与规律，就很难搞好专业英语的阅读、翻译和写作。为了掌握这些特点和规律，本章及下一章节将主要介绍专业英语的语法特点和词汇特点。一专业英语的语法特点一专业英语的语法特点v1 无人称（无人称（Impersonal）（无生命的第三人称语气或非人）（无生命的第三人称语气或非人称语气）称语气）科技文体第一个显著的特点就是较多地使用无生命的第三人称语气。例如：Stepper motors are useful wherever accurate control of movem

28、ent is required.They are used extensively in robotics and in printers,plotters and computer disk drives,all of which require precise positioning or speed.凡需要精确控制运动的地方,步进电机都非常有用。他们广泛用于机器 人技术,打印机,绘图仪和计算机磁盘驱动器，这些需要精确的定位或速度。v2被动语态被动语态(Passive Voice)由于专业英语文献侧重叙事和推理，陈述的对象是客观事物。读者重视的是作者的观点和发明的内容，而不是作者本人。因此

29、在语言表述中必然较多地使用以客观事物为主体的被动语态。专业英语中的被动语句不一定要说出行为主体，特别当行为主体是人 时。但有时也用“by”引出行为者。这些行为者除了人、机构、物质以 外，还包括完成该动作的方法、原因或过程等。例如：The temperature of the liquid is raised by the application of heat.加热可以提高液体温度。The rate at which work is done is called power.v3非谓语动词非谓语动词 动词非谓语形式有：动名词、分词、动词不定式及它们的复合结构。专业英语中，动词的非谓语形式应用广

30、泛，这是因为专业英语要求准确、精炼，而动词的非谓语形式可以很好地实现这些要求。比如采用这一形式能用扩展的成分对所修饰的词进行严格的说明和限定。其中每一个分词定语都能代替一个从句，从而可使很长的句子匀称,避免复杂的主从符合结构，并省略动词时态的配合，使句子即不累赘又语意明确。3.1 分词的使用分词的使用 在专业英语中，分词短语被大量地用作定语、状语和独立分词结构，取代被动态或主动态的关系从句，使句子结构得到简化。例如：1.Rammers driven by compressed air can increase the production rates.压缩空气驱动的舂砂器可以提高生产效率。2.

31、Originally designed for rapid,automatic production of screws and similar threaded parts,the automatic screw machine has long since exceeded the confines of this narrow field,and today plays a vital role in the mass production of a variety of precision parts.自动螺丝车床最初是用来对螺钉和类似的带有螺纹的零件进行自动 化快速加工的。但是，这种

32、车床的用途早就超过了这个狭窄的范围。现 在，它在许多种类的精密零件的大批量生产中起着重要的作用。分词独立结构，即：名词或代词分词短语，是一种主谓结构，在句 中的作用相当于并列分句或从句。例如：3.Agitation is critical,the aim being to distribute silicon carbide particles homogeneously throughout the aluminum melt.搅拌至关重要，其目的是将碳化硅颗粒均匀地分布在整个铝液中。分词独立结构前加with(without)变成起状语作用的介词短语，用于当 分词的逻辑主语与句子主语不一致时

33、。4.In the heat exchanger of blast furnace the air flows through the outside pipe,the gas through the inside pipe,with heat exchange taking place through the wall.在高炉热交换器中，空气流过外管，燃气流过内管，热交换通过管 壁进行。3.2 动名词的使用动名词的使用 动名词构成的介词短语可取代状语从句或简化陈述句，在英语中广泛 应用。例如：In redesigning an experimental part for production

34、,economical tolerances should be used.为了生产而重新设计试件时,必须使用经济公差。v3.3 不定式的使用不定式的使用 不定式在专业英语中的使用也十分频繁，在句中常用来替换表示目的功能的从句，使句子结构简练。例如：1.To insure manufacture quality of electrodes,the American Welding Society has set up certain requirements for electrodes.为了确保电极的制造质量，美国焊接学会规定了电极必须具备的一些条件。2.There is high requ

35、irement of skill in carrying out this operation to produce products with high performances.进行这项操作时需要很高的技巧，以生产出具有高性能的产品。4.名词化结构名词化结构 “表示动作意义的名词of名词修饰语”叫做名词化结构。名词化结构具有文字明了、用词简洁、结构紧凑、表意客观、信息容量大等特点，在专业英语中经常用它代替主、谓结构作各种句子成分，使句子结构简化。例如:用普通英语表达这样一句话：The ultrasonic metal inspection is to apply ultrasonic vi

36、brations to materials with elastic properties and to observe the resulting action of the vibrations in the materials.用名词化结构如下表述：The ultrasonic metal inspection is the application of ultrasonic vibrations to materials with elastic properties and the observation of the resulting action of the vibratio

37、ns in the materials.金属超声波探伤是将超声振动施于具有弹性的材料，并观察振动在材料中产生的作用。二专业英语的词汇特点二专业英语的词汇特点v专业英语词汇的组成专业技术词汇：polymerization 聚合作用 diathermometer 热阻测定仪 mechatronics 机电一体化，机械电子学 lathe 车床半专业技术词汇：power 力量,权力（日常英语）动力 （机械专业）电力 （电力专业）幂 (数学专业）功率 （物理专业）爆发力 （体育专业）v构词法 英语的构词法包括转化、合成、派生三种形式。转化(conversion)如：melt 熔液to melt熔化 fi

38、nish光洁度to finish精加工、抛光 alloy 合金to alloy 使成合金复合法(composition)如：waveform 波形 ballbearing 滚珠轴承 workshop 车间 toolroom 工具室派生或词缀(derivation)如：unavoidable 不可避免的 inaccuracy 不精确v词汇缩略首字词缩略:它是由原词组的每个词首字母组成，在阅读中首字词要逐字母读.例如：NC 数控 AC 自适应控制 PLC 可编程控制器 AIEE American Institute of Electrical(Electronic)Engineers 美国电气（电

39、子）工程师学会首字词拼音:把一个词组中的首字母拼凑成一个词.例如 laser light amplification by stimulated emission of radiation 激光 ROM read only memory 只读存储器 AIDS acquired immune deficiency syndrome 爱滋病v节略词:某些词使用频率高,为了方便，在发展过程逐渐用 它们的前几个字母来表示。例如：ref.reference 参考文献 lab.laboratory 实验室 in.inch 英吋 ft.foot 英呎v缩写词 例如：etc.et cetera 等等 i.e

40、that is 即 e.g.for example 例如 vs.versus 对 v 拼缀:即以组成复合词的各个词中各抽取一或两个词缀相 拼合。例如：transeiver (transistor receiver)收发机 mechatronics (mechanics electronics)机电一体化vdistinguish 区别；区分区别；区分 distort:变形变形vby means of:借助于借助于 permanent:永久的永久的vcoefficient:系数系数 steel mill:钢厂钢厂vexpansion：膨胀：膨胀 roll:轧锟轧锟vreact to:对对.起作用起

41、作用;对对.的反应的反应 crack:裂开裂开,裂纹裂纹,破裂破裂vin connection with:与与.有关有关 gradually:逐渐地逐渐地 vfive broad categories:五大类五大类velasticity:弹性弹性vductility:延展性延展性vtoughness:韧性韧性velevator:升降机升降机 vcable:电缆电缆vbeam:横梁横梁vpenetration:压痕压痕,凹痕凹痕vabrasion:磨损磨损velongate:延长，伸长延长，伸长Lesson 2 Metals and Ferrous Metalsvferrous a.铁类的，黑色

42、的 nonferrous a.有色的vtwo general types 两大类 broad main vHowever,some nonferrous metals may contain a small amount of iron as an impurity.a small amount of:少量的 a large amount of:大量的 varying amounts:不同数量的vSteel and cast iron are the most common ferrous metals in general use.cast iron 铸铁 general use 普通的用途

43、vSteel is an alloy containing chiefly iron,and certain other elements in varying amounts.vA wide range of physical properties may be obtained in steel by controlling the amount of carbon and other alloying elements and by subjecting the steel to various heat treatment.a wide range of:各种各样的，形形色色的 be

44、subjected to:易受到，承受 subject sth.to:使.承受.vAlloy steels are formed by the addition of one or more of the following elements.vby far:迄今vIt is the amount of carbon present which largely determines the maximum hardness obtainable.It is+强调部分+which.vThe higher the carbon content,the higher the tensile stre

45、ngth and the greater the hardness to which the steel may be heat-treated.The steel may be heat-treated to the hardness.v.parts requiring a great deal of forming.a great deal of:大量vMedium-carbon steels are used for forgings and other applications where increased strength and a certain amount of ducti

46、lity are necessary.vAlloy steels have special properties determined by the mixture and the amount of metals added.mixture:混合物金属种类vTo the metallurgist who works in metal mining and manufacturing,steels containing very small quantities of elements other than carbon,phosphorus,sulphur,and silicon are k

47、nown as alloy steels.work in：从事other than：除了.be known as:叫做,称为be known for.:因.而著名be known to:被知道vEach alloy steel has a personality of its own.vTool-and-die steels are a large group of steels used when careful heat-treating must be done.vThese steels are used for parts such as chisels,hammers,screwd

48、rivers,springs,and tools and dies used to cut and form metals.vTool steels with certain alloying elements are designed for specific uses.be designed to.设计成能(做),用来,目的是使 be designed for.用做用途;为.而设计specific:a.1.比率，单位的 e.g:specific heat,specific weight 2.特殊(定,有,种)的;专门的;具体的,明确的 vThe most common kinds of t

49、ool steels include high-speed tool steels,hot work tool steels,cold work tool steels and special-purpose tool steels.hot work tool steels 热加工工具钢 cold work tool steels 冷加工工具钢special-purpose 专用的 special-purpose machines general-purpose 通用的 general-purpose machinesvRolled steel,which includes bar,rod,a

50、nd structural steels,is produced by rolling the steel into shape.bar 扁钢rod 圆钢by rolling the steel into shape 轧制成形的方法.vHot-rolled steels are formed into shape while the metal is red-hot.are formed into shape 成形vThe metal passes through a series of rollers,each a little closer to the next one.roller:轧