机械专业英语课件Unit4.ppt

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1、第第第第 1 1/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextTextHeat Treatment&Hot Working of MetalsUnit 4金属的热处理和热加工金属的热处理和热加工1第第第第 2 2/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextTextHeat Treatment and Working Equipment2第第第第 3 3/5/54 4页页页页上一页上一页上一页上一页下一页下一页下

2、一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextTextTesting Before ClassTesting Before Class：What the meaning of“Shaping”?(radio)3第第第第 4 4/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextTextHeat Treatment&Hot Working of MetalsHeat Treatment&Hot Working of Metals 4第第第第 5 5/5/54 4页页页页上一页上一

3、页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText We can alter the characteristics of steel in various ways.In the first place,steel which contains very little carbon,will be milder than steel,which contains a higher percentage of carbon,up to the limit of about 1.5.Secondly,we can heat the

4、steel above a certain critical temperature,and then allow it to cool at different rates.At this critical temperature,changes begin to take place in the molecular structure of the meta1.In the process known as annealing we heat the steel above the critical temperature and permit it to cool very slowl

5、y.This causes the metal to become softer than before,and much easier to machine.5第第第第 6 6/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText Annealing has a second advantage.It helps to relieve any internal stresses which exist in the metal.These stresses are liable to occur th

6、rough hammering or working the metal,or through rapid cooling.Metal which we cause to cool rapidly contracts more rapidly on the outside than on the inside.This produces unequal contraction,which may give rise to distortion or cracking.Metal which cools slowly is less liable to have these internal s

7、tresses than metal,which cools quickly.6第第第第 7 7/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextTextOn the other hand,we can make steel harder by rapid cooling.We heat it up beyond the critical temperature,and then quench it in water or some other liquid.The rapid temperature dr

8、op fixes the structural change in the steel,which occurred at the critical temperature,and makes it very hard.But a bar of this hardened steel is more liable to fracture than normal steel.We therefore heat it again to a temperature below the critical temperature,and cool it slowly.This treatment is

9、called tempering.It helps to relieve the internal stresses,and makes the steel less brittle than before.The properties of tempered steel enable US to use it in the manufacture of tools,which need a fairly hard steel.High carbon steel is harder than tempered steel,but it is much more difficult to wor

10、k.7第第第第 8 8/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextTextThese heat treatments take place during the various shaping operations.We can obtain bars and sheets of steel by rolling the metal through huge rolls in a rolling mill.The roll pressures must be much greater for cold

11、 rolling than for hot rolling,but cold rolling enables the operators to produce rolls of great accuracy and uniformity,and with a better surface finish.Other shaping operations include drawing into wire,casting in moulds,and forging.8第第第第 9 9/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英

12、语 徐存善主编TextTextThe mechanical working of metal is the shaping of metal in either a cold or a hot state by some mechanical means.This does not include the shaping of metals by machining or grinding,in which processes metal is actually machined off,nor does it include the casting of molten metal into

13、some form by use of molds.In mechanical working processes,the metal is shaped by pressure-acutely forging,bending,squeezing,drawing,or shearing it to its final shape.In these processes the metal may be either cold or hot worked.Although normal room temperatures are ordinarily used for cold working o

14、f steel,temperatures up to the re-crystallization range are sometimes used.Hot working of metals takes place above the re-crystallization or workhardening range.9第第第第 1010/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextTextFor steel,re-crystallization starts around 650 to 700C,a

15、lthough most hot work on steel is done at temperatures considerably above this range.There is no tendency for hardening by mechanical work until the lower limit of the re-crystalline range is reached.Some metals,such as lead and tin,have a low re-crystalline range and can be hot worked at room tempe

16、rature,but most commercial metals require some heating.Alloy composition has a great influence upon the proper working range,the usual result being to raise the re-crystalline range temperature.This range may also be increased by prior cold working.10第第第第 1111/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英

17、语机电专业英语机电专业英语机电专业英语 徐存善主编TextText molecular mlekjl a.由分子组成的,分子的annealing ni:li n.(低温)退火，焖火，磨炼relieve rili:v v.解除，减轻，使不单调乏味liable laibl a.有责任的，有义务的，应受罚的，有倾向的contract kntrkt v.收缩，缩紧，感染，订约 rise raiz v.上升，增强，起立，高耸shaping eipi n.成形，造型，塑造mechanical miknikl a.机械的，呆板的，力学的machining mi:ni n.切肖，制造，机械加工grinding

18、 raindi n.磨肖力工machined mi:nd a.机械加工的pressure pre n.压力，压强bend bend v.使弯曲，使屈服，使致力，使朝向bending bendi n.弯曲(度)，扭曲(度)New words and New words and phrasesphrases11第第第第 1212/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText squeeze skwi:z v.挤(压，干)，压榨，勒索，紧握prior prai a.在先的，在前的，优先的distort

19、ion dist:n n.变形，扭曲，曲解，失真crack krk v.&n破裂，裂纹，打开beyond bijnd prep.超过的范围,超过,越过quench kwent v.&n熄灭，机 淬火,解渴；fix fiks v.&n.安装,修理，使固定，准备 tempering tempri v.回火 rolls ruls n.薄板卷，泛指钢材 draw dr:v.拉,画,吸引 drawing dr:i n.冲压成形shear i v.剪断，切断，修剪，剥夺recrystallization ri:,kristlaizein n.再结晶hardening h:dni n.硬化，淬火,锻炼cry

20、stalline kristlain a.结晶的凡结晶体influence influns n.影响，作用New words and New words and phrasesphrases12第第第第 1313/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText mechanical means 机械设备(工具)be known as 称为workhardening range淬火温度区Technical Terms13第第第第 1414/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一

21、页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText 1.This produces unequal contractions，which may give rise to distortion or cracking译文：这将引起不均匀压缩，增加其出现畸变和破裂的可能。说明：此句为非限定性定语从句。“Which”引导的从句时对“unequal contractions”的进一步解释说明。Language points14第第第第 1515/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存

22、善主编TextText2.This does not include the shaping of metals by machining or grinding，in which processes metal is actually machined off，nor does it include the casting of molten metal into some form by use of molds 译文：这既不包括金属已经过机械或磨削加工的成形，也不包括熔化的金属注入铸造模所进行的成形。说明：“in which processes metal is actually mac

23、hined off”为非限定性定语从句，对前面的主句起进一步解释说明作用。“nor does it include the casting of molten metal into some form by use of molds”此句为倒装句，由于“nor”提前，整个句子发生了部分倒装。Language points15第第第第 1616/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText 3.These stresses are liable to occur through hammering

24、 or working the metal,or through rapid cooling.金属在锻打加工或快速冷却时外层收缩比内层收缩速度快，极易导致内应力。be liable to:易于的；有倾向的；应付有责任，应遵守 (1)A third party,whose fault causes the fuel gas accident,shall be liable to pay damages according to law.因第三人的过错造成燃气事故的，第三人应当依法承担损害赔偿责任。(2)Non-complying trusts are also deemed to be liab

25、le to taxation on the trusts worldwide income.“非照办信托”同时也被推定为按其信托之全球收入征税。Language points16第第第第 1717/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText4.We heat it up beyond the critical temperature,and then quench it in water or some other liquid.我们将金属加热到超过极限温度，然后在水或其他液体中淬火。heat

26、 up：加热 （1）The electronic heater can heat up fast and safely.It also functions as a steamer.以电热为燃料能源，既方便，而且加热速度快，有蒸气锅炉之同功效。（2）Material spiraling into a black hole can heat up to millions of degrees and glow brightly.捲入黑洞中的物质，将会被加热至数百万度并放出耀眼的光芒。Language points17第第第第 1818/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一

27、页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText5.The properties of tempered steel enable US to use it in the manufacture of tools,which need a fairly hard steel.当制造的工具需要高硬度的钢铁时，我们可以用回火钢。enable to:使;使能够;能够(1)Using ICON controlling circuit,enable to detect the status of the mechanism operation.本机采用ICON控制回路

28、，可侦测机械操作状况。(2)The space between the inner and outer plate is full of heat insulation materials which enable to provide the nice performance of heat insulation.内外板之间形成的空间可以填充保温材料，能够提供良好的保温功能。Language points18第第第第 1919/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText6.Other sha

29、ping operations include drawing into wire,casting in moulds,and forging.其他的塑性加工有拉丝、模铸和锻造。drawing into:使卷入(1)SMS Draw integrates into the target application and appears as a new service in the toolbar.短信抽奖集成到目标应用，似乎作为一种新的服务工具栏。(2)Now the pattern repeat with manual twist,will itself draw into the acti

30、ve level of the Photoshop data file and the original is maintained again on a separate level.现在的模式重复与手工捻，本身将提请进入活跃水平的Photoshop的数据文件和原再次是保持在一个单独的水平。Language points19第第第第 2020/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText7.There is no tendency for hardening by mechanical wor

31、k until the lower limit of the re-crystalline range is reached.在达到最低的再结晶温度之前，机械加工的金属没有硬化的趋势。tendency tendnsi n.倾向，趋势；癖好(1)Since gravity works equally on everything,there would be a tendency to pull those uneven places down.由于重力作用于物体上是相等的，会有倾向于将受力不相等的地方拉平。(2)The tendency of modern science is to reduc

32、e proof to absurdity by continually reducing absurdity to proof.现代科学的倾向，是不断把谬论化为根据来使实证变得荒谬。Language points20第第第第 2121/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText8.Alloy composition has a great influence upon the proper working range,the usual result being to raise the re

33、-crystalline range temperature.合金的成分对合适的加工范围有极大的影响，通常会提高再结晶的温度范围。have/has influence upon:有影响(1)The level of weighting rate has direct influence upon the fabric properties.增重率的高低对织物性能有直接影响。(2)In the legal system of termination of labor contract,dismissal system has great influence upon employee.劳动法律关

34、系解除法律制度中，解雇制度对劳动者权益的影响尤其重大。Language points21第第第第 2222/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextTextI.Answer the following questions.1.Explain the ways that can alter the characteristics of steel In the first place,steel which contains very little carbon,will be milder than

35、 steel,which contains a higher percentage of carbon,up to the limit of about 1.5.Secondly,we can heat the steel above a certain critical temperature,and then allow it to cool at different rates.On the other hand,we can make steel harder by rapid cooling.keykeyExercises22第第第第 2323/5/54 4页页页页上一页上一页上一页

36、上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText 2.What are the advantages of annealing?In the process known as annealing we heat the steel above the critical temperature and permit it to cool very slowly.This causes the metal to become softer than before,and much easier to machine.Annealing ha

37、s a second advantage.It helps to relieve any internal stresses which exist in the metal.These stresses are liable to occur through hammering or working the metal,or through rapid cooling.keykeyExercises23第第第第 2424/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText 3.What is the

38、 meaning of tempering?We heat up the steel beyond the critical temperature,and then quench it in water or some other liquid.The rapid temperature drop fixes the structural change in the steel,which occurred at the critical temperature,and makes it very hard.But a bar of this hardened steel is more l

39、iable to fracture than normal steel.We therefore heat it again to a temperature below the critical temperature,and cool it slowly.This treatment is called tempering.keykeyExercises24第第第第 2525/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText 4.What is the temperature at which

40、steel starts to re-crystallize?For steel,re-crystallization starts around 650 to 700C.keykeyExercises25第第第第 2626/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText1.金属的分子结构 2.不均匀压缩3.快速冷却4.各种塑性加工IITranslate the following into Englishstructure of the meta1unequal contractionrapid

41、 coolingvarious shaping operationskeykeykeykeykeykeykeykey26第第第第 2727/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText5.金属的机械加工6.金属的冷热加工mechanical working of metalcold or hot working of steelkeykeykeykey.Put the phrases into English:27第第第第 2828/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页

42、下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText 在翻译过程中，由于英汉两种语言的表达方式不同，不能逐词对译。原文中有些词在译文中须要转换词性，才能使译文通顺流畅。词性转译的几种情况如下：一、英语动词、形容词、副词译成汉语名词 1.Telecommunications means so much in modern life that without it our modern life would be impossible.电信在现代生活中意义重大，没有它就不可能有我们现在的生活。词性转译词性转译TranslatingTranslating28第第第第 2

43、929/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText 2.Gases differ from solids in that the former has greater compressibility than the latter.气体和固体的区别在于气体的可压缩性比固体大。3.The instrument is characterized by its compactness and portability.这个仪器的特点是结构紧凑，携带方便。TranslatingTranslating29

44、第第第第 3030/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText二、英语名词、介词、形容词、副词译成汉语动词二、英语名词、介词、形容词、副词译成汉语动词 1.Substitution of manual finishing is one example of HSM application.替代手工精加工是高速加工应用的一个例子。2.Scientists are confident that all matter is indestructible.科学家们深信一切物质是不灭的。3.The ap

45、plication of electronic computers makes for a tremendous rise in labor productivity.使用电子计算机可以大大提高劳动生产率。TranslatingTranslating30第第第第 3131/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextText三、英语的名词、副词和动词译成汉语形容词三、英语的名词、副词和动词译成汉语形容词 1.This wave guide tube is chiefly characterized by

46、 its simplicity of structure.这种波导管的主要特点是结构简单。2.The maiden voyage of the newly built steamship was a success.那艘新造轮船的处女航是成功的。3.It is a fact that no structural material is perfectly elastic.事实上没有一种结构材料是十全十美的弹性体。TranslatingTranslating31第第第第 3232/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语

47、 徐存善主编TextText四、英语形容词、名词译成汉语副词四、英语形容词、名词译成汉语副词 1.Quasi-stars were discovered in1963 as a result of an effort to overcome the shortcomings of radio telescopes.类星体是1963年发现的，是人们努力克服射电望远镜的缺点所取得的一项成果。2.A continuous increase in the temperature of a gas confined in a container will lead to a continuous inc

48、rease in the internal pressure within the gas.不断提高密封容器内气体的温度，会使气体的内压力不断增大。TranslatingTranslating32第第第第 3333/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextTextSoldering and WeldingSoldering and WeldingThere are a number of methods of joining metal articles together,depending on

49、the type of metal and the strength of the joint that is required.1.Soldering and Brazing钎焊和焊接钎焊和焊接钎焊和焊接钎焊和焊接 金属连接在一起的方法很多，选用哪种方法要取决于金属的类别和所要求的接缝强度。1.软钎焊与硬钎焊 ReadingReading33第第第第 3434/5/54 4页页页页上一页上一页上一页上一页下一页下一页下一页下一页机电专业英语机电专业英语机电专业英语机电专业英语 徐存善主编TextTextSoldering gives a satisfactory joint for ligh

50、t articles of steel,copper or brass,but the strength of soldered joint is rather less than a joint which is brazed,riveted or welded.These methods of joining metal are normally adopted for strong permanent joint.Soldering is the process of joining two metals by a third metal to be applied in the mol