材料成型及控制工程专业英语-_1.MATERIALS_AND_THEIR_PROPERTIES.ppt

1、材料成型及控制工程专业英语,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,1.1 Metals and Non-metals Words and terms definite确定的、明确的 defect缺陷 plastic deformation塑性变形 stress concentrator 应力集中点 self-strengthening自强化 the tip of a crock裂纹尖端,- 1 -,- 2 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,Among numerous properties poss

2、essed by materials，their mechanical properties，in the majority of cases，are the most essential and therefore，they will be given much consideration in the book,在一些主要应用场合，机械性能是材料的各种性能中最重要的性能，因此，本书中将重点讨论。,consideration 考虑，需要考虑的事项，报酬,- 3 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,All critical parts and

3、elements，of which a high reliability（可靠性）is required，are made of metals, rather than of glass，plastics or stone.,由于各种关键零部件的可靠性要求高，均用金属而不是玻璃、塑料或石头制造。,is required 翻译时将英文中的被动语态，改译为汉语中的主动语态。,rather than 而不是,- 4 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,As has been given in Sec.1-1，metals are characteri

4、zed by the metallic bond（金属键），where positive ions （正离子）occupy the sites of the crystal lattice （晶格）and are surrounded by electron gas（电子云） ,正如Sec1-1中所说，金属主要由金属键组成（其特征主要）。金属键就是正离子占有晶格位置，周围包围着电子云。,- 5 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,All nonmetals have an ionic or a covalent bond(共价键)，these

5、types of bond are rigid and are due to electrostatic attraction of two ions of unlike charges,非金属主要由离子键或者共价键组成。这些类型的化学键不是通过电荷间，而是离子间的静电吸引连接在一起的。这种连接是刚性的。,Bond n. 结合(物), 粘结(剂), 联结, 公债, 债券, 合同,- 6 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,Because of the metallic bond，metals are capable of plastic def

6、ormation （塑性变形）and self-strengthening（加工硬化） upon plastic deformation. Therefore , if there is a defect（缺陷） in a material or if the shape of an element is such that there are stress concentrators ,the stresses in these points may attain a great value and even cause cracking .,由于具有金属键，金属在(塑性)变形时具有塑性以及

7、在塑性变形基础上产生的加工硬化的象。因此，如果材料或者其某部分中有缺陷，会导致应力集中，在这些点的应力会达到很大甚至产生裂纹。,- 7 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,but since the plasticity of the material is high，the metal is deformed plastically in that point，say，at the tip of a crack，undergoes strengthening, and the process of fracture comes to an a

8、rrest. Arrest-t停止、扣留、制动、逮捕。Fracture裂纹、断裂,但是由于材料的塑性好，金属可以在这些位置产生塑性变形，即：裂纹尖端产生硬化，会推迟断裂过程的产生。,- 8 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,This does not occur in non-metalsThey are uncapable of plastic deformation and self-strengthening. Therefore, fracture（断裂） will occur as soon as the stresses at t

9、he tip of a defect exceed a definite value,这一现象则不会在非金属中出现。非金属不能进行塑性变形和发生加工硬化现象。因此，一旦某处缺陷的应力超过某一定值后，就会产生断裂。,- 9 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,These facts explain why metals are reliable structural materials and can not be excelled by nonmetallic materials,Excelled 胜过,超过,优于,超越,这些现象可以解释为什么

10、金属可以作为可靠的结构材料而非金属却不能(的原因)。,“why” is the object clause.,- 10 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,deoxidafion脱氧 hot-rolled steel热轧钢 beam线材 State Standard国家标准 forging锻造 alloying element合金元素 harmful impurity有害杂质 welding焊接 stamping冲压,1.2 Ferrous Alloys,magnesium 化镁 manganese化锰(元素符号为Mn) phosphorus磷

11、 sulphur 硫 impurity n.杂质, 混杂物, 不洁, 不纯 plain carbon steel普通碳钢 bar棒材 sheet板材,- 11 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,More than 90 by weight of the metallic materials used by human beings are ferrous alloys. This represents an immense family of engineering materials （工程材料）with a wide range of m

12、icrostructures and related properties,人类所用的金属材料中90的都为铁合金。这则说明功能材料种类繁多，其组织和性能也各种各样。 Note：the long sentence should be decomposed into clause ( short sentence).,- 12 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,The majority of engineering designs that require structural load support or power transmission

13、 involve ferrous alloys,工程设计中主要要求铁合金能够承受结构载荷或进行能量传输。,- 13 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,As a practical matter，these alloys fall into two broad categories based on the carbon in the alloy composition. Steel generally contains between 0.05 and 2.0 wtcarbon The cast irons generally contain

14、 between 2.0 and 4.5 wtcarbon wt%weight percent carbon碳,实际应用时，根据(铁)合金中碳含量将其分为两大类：钢铁一般含有0.05-2.0wt的碳，铸铁一般含有2.0-4.5wt的碳。,- 14 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,Within the steel category，we shall distinguish whether or not a significant amount of alloying elements other than carbon is usedA co

15、mposition of 5wt total non-carbon (非碳元素) additions will serve as all arbitrary boundary between low alloy and high alloy steels,在钢的分类中，我们还需明确是否使用了大量的合金中非碳合金元素。高合金钢和低合金钢的严格界限在于非碳合金元素的含量是否超过了5%wt.,- 15 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,These alloy additions are chosen carefully because they i

16、nvariably bring with them sharply increased materials costsThey are justified only by essential improvements in properties such as higher strength or improved corrosion resistance,因为合金元素的加入会导致材料成本的明显上升，所以，选择加入合金元素时需谨慎。只有加入合金元素能改善材料性能，比如提高强度或改善抗腐蚀性时，合金的添加才比较合理。,“they”in the second sentence refer to“t

17、hese alloy additions”in the first sentence.,- 16 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,1.2.1 Plain Carbon Steel 普通碳钢 Hot-rolled steel delivered （供给）by steelmaking works as rolled sections(bars, beams，sheetstubes，etc) is the most wildly used material for manufacture of various machines，machine t

18、ools, building structures，consumer goods，etcDelivered steel should have the properties as specified by State Standards（国家标准）,钢铁制造车间供给的热轧钢主要为棒材、柱材、板材、管材等，热轧钢是制造各种机械、机器工具、建筑结构和消费品中应用最广泛的材料。所供给的钢应具有国家标准规定的各种性能。,“delivered ”act as attribute.,- 17 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,In the RSSUPla

19、in carbon steels are classified into three groups：A, B and C，depending on their application.,在RSSU中，普通碳钢根据其用途分为A、B、C三类。,RSSU 可能代表的简写？,- 18 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,A: If a steel is to be used for making products without hot working (welding, ForgingEtc.). Its structure and properti

20、es in the final product will be the same as delivered from the rolling mill,A:如果钢在制造产品的过程中没有进行热加工（焊接、锻造等），则最终产品的组织和性能将与轧厂提供的相同。 hot working 热加工-在再结晶温度以上成形加工 welding, 焊接 Forging锻造,- 19 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,In that case the user requests for a steel of warranted（保证） mechanical pr

21、operties，while the chemical composition is not guaranteed（保证、担保）,这种情况下，用户只需要求材料应有的机械性能，而不必保证其成分。 Warrant保证的 Guarantee vt. 保证, 担保 “While .”表示语意的转折，但不如转折意味“but”明显 。,- 20 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,B: If a steel is to be subjected to hot working(forging，stamping，etc)，its initial structu

22、re and mechanical properties will be changed .,B.如果钢要进行热加工（锻造、冲压等），则其初始组织和机械性能将会改变。 Stamping冲压,- 21 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,In that case the composition of the steel will be of prime importance for the user，since it determines the conditions of hot working and the final mechanical

23、 properties of steel productsNow a steel of warranted composition is delivered to the user.,此时/在这种情况下，钢的成分对用户来讲是最重要的，因为它(成分)决定了热加工的条件，钢制品的最终机械性能。因此，提供给用户的钢应保证其成分含量。 prime adj.主要的, 最初的, 最好的, 第一流的, 根本的,- 22 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,C: If a steel is to be weldedthe user wants to know

24、the composition of the steelsince it determines the properties of the metal in the zone subjected to thermal effect of weld（焊接热影响区）,C如果钢要进行焊接，则用户需要知道钢的成分，因为成分决定钢焊接时热影响区的性能。,- 23 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,The user is also interested in the initial mechanical properties of the metal，s

25、ince these properties will remain the same in portions not subjected to weldingIn that case the metal is delivered with warranted composition and mechanical properties.,用户也会对钢材的原始机械性能感兴趣，因为未焊接的部分的性能是原始性能。这种情况下，供给用户的钢应具有规定的成分和机械性能。,“not subjected to welding” act as attribute.,- 24 -,CHAPTER 1 MATERIA

26、LS AND THEIR PROPERTIES,General-purpose plain steels are not alloyedSome alloying elements may sometimes be present in them occasionally and their content（含量） is limited,非特殊用途/一般用途的普通钢不是合金钢。一些合金元素偶尔会出现，其含量受限制。,- 25 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,The presence of silicon and manganese may

27、be due to the steelmaking process(the necessity of deoxidation脱氧)Surphur（硫）and phosphorus（磷） are harmful impurities（杂质） in steel and their content should be minimized as it may affect the quality of steel,在钢冶炼过程中由于脱氧的需要，会出现硅和锰。硫、磷是钢中有害的杂质，应尽可能减少其含量，它们会影响钢的质量。,“as.”induct the adverbial clause of caus

28、e,- 26 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,The principal element whose content is responsible for the properties of steels is carbon,影响钢性能最主要的元素是碳。,- 27 -,1.2.2 Low Alloy Steels Proprietary专利、所有人， specified规定、指定。 Optimal最优、最佳 elevate提高。 Low alloy steel 低合金钢 eminently杰出地 HSLA低合金高强度钢 ductile可延展

29、的；可锻的 proprietary特定的 stress relief应力松驰,- 28 -,- 29 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,The majority of ferrous alloys belongs to this category. The reasons for this are straight-forward(显而易见). They are moderately priced due to the absence of large amounts of alloying elements, and they are su

30、fficiently ductile(延展性) to be readily formed. The final product is strong and durable.,大多数铁合金属于低合金钢,其中的原因是显而易见的，低合金钢中缺乏大量的合金元素，使其价格适中，并具有足够的塑性/延展性以满足成形的要求。最终产品结实耐用。,- 30 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,These eminently practical materials find applications form ball bearings to metal sheet

31、s formed into automobile bodies.,这些不同寻常的材料实际运用涉及球轴承以及金属板材制成的汽车车身。,ball bearings 球轴承,Eminently adv. 闻名的, 卓越的, 显赫的,- 31 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,The designation of ferrous alloys is specified by digits（阿拉伯数字） such as 10 xx，11XX，12XX，15KX etc(AISI standards，in which the first two numb

32、ers gives a code designating the type of alloying additions and the last two or three numbers give the carbon content in hundredths of a weight percent).,铁合金的(设计)牌号主要用阿拉伯数字表示为10XX, 11XX, 12XX, 15XX等。（AISI标准中，前两个数字用来表明添加合金的规定牌号，后两个数字表示碳的重量百分比。）,AISI American Iron and Steel Institute 美国钢铁学会,- 32 -,CHA

33、PTER 1 MATERIALS AND THEIR PROPERTIES,As an example , the plain carbon steel with 0.40 wtcarbon is a 1040 steel，whereas a steel with 1.45 wtCr and l.50 wtcarbon is a 52150 steel .,例如，含0.40C的普通碳钢，其牌号为1040钢，而含1.45Cr和1.50C则表示为52150钢。,Cr 化铬 (chromium),- 33 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,One

34、should keep in mind that chemical compositions quoted in alloy designations are approximate(近似的) and will vary slightly from product to product within acceptable limits of industrial quality control.,我们应该记住，合金牌号中的化学成分是近似值，在工业质量控制可接受的范围内，产品之间的(成分)范围有细微差别。,Quote vt. 引用, 引证, 提供, 提出, 报(价) “quoted”acted

35、as attribute.,- 34 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,An interesting class of alloys known as high strength low alloy(HSLA) steels has emerged in response to requirements for weight reduction of vehicles. The composition of many commercial HSLA steels are proprietary and specified by mechani

36、cal properties rather than composition.,为了满足汽车减重要求而出现了高级高强度低合金钢。许多商用HSLA钢是根据其性能尤其是机械性能而不是成分来确定的。,- 35 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,But typical example might contain 0.2 wt% carbon and about 1.0wt% or less of such elements as Mn, Si, Cr, W, Ni or Mo.,但是典型的HSLA钢包含0.2wtC，Mn、Si、Cr、W、i等含量不超

37、过1.0wt。,Mn 锰(manganese),Cr 化铬 (chromium),W 钨 tungsten,Ni 镍(nickel),Mo 钼(molybdenum),- 36 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,The strength of HSLA steels is the result of optimal alloy selection and carefully controlled processing such as hot rolling (deformation at temperatures sufficiently e

38、levated to allow some stress relief).,通过选择最合适的合金并谨慎控制的热轧成形等工艺，来获得HSLA钢的强度。(热轧是在温度充分提高的条件下钢板进行变形，使其一部分应力得以释放。),- 37 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,1.2.3 High Alloy Steel turbine蜗轮机 austenitic奥氏体的 bcc体心立方 tetragonal四角的 curler刀具 dislocation位错 molybdenum钼,rust生锈 fcc面心立方 ferritic铁紊体的 martensi

39、te马氏体 precipitation沉淀 tungsten钨 cobalt钻,- 38 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,1.2.3 High Alloy Steel As mentioned above, alloy additions must be made with care and justification because they are expensive. We shall now look at three cased in which engineering design requirements justify hi

40、gh alloy composition(i.e., total non-carbon additions greater than 5wt%).,如上所说，因为其价格昂贵，添加合金必须适当。现在，我们看三个例子，这些例子是关于工程设计中所要求的合适的高合金成分。（即，添加的非碳合金含量不超过5wt）,- 39 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,Stainless steels require alloy additions to prevent damage from a corrosion atmosphereTool steels re

41、quire alloy additions to obtain sufficient hardness for machining applications . So it is called “superalloys” which require alloy additions to provide stability in high temperature applications such as turbine blades,不锈钢中添加的合金元素用来阻止腐蚀性气氛的破坏。工具钢中添加的合金元素主要是为了获得机械加工中所需的硬度。因此它也叫“超合金”，这需要添加的合金可以提供高温工作时的

42、稳定性，比如涡轮机叶片。,- 40 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,Stainless steels are more resistant to rusting and staining than carbon and low alloy steels，due primarily to the presence of chromium addition. The amount of chromium is at least 4wtand usually above 10 wt，levels as high as 30wtCr are som

43、etimes used. Rust铁锈 staining浸蚀 chromium铬,不锈钢比碳钢和低合金钢更不易产生铁锈和锈蚀，这主要归功于铬的加入。铬含量至少4wt，一般在10wt以上。有时也高达30wt。,- 41 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,The austenite stainless steels have the austenitic structure retained at room temperatureThe austenite has the fcc structure and is stable above 910

44、.This structure can occur at room temperature, when it is stabilized by an appropriate alloy addition such as nickelWithout the high nickel content，the bcc structure is stable，as seen in the ferrite stainless steels,奥氏体不锈钢在室温下含有奥氏体组织。奥氏体为面心立方结构，在910时依然稳定。通过加入Ni，奥氏体稳定性提高，室温下就可产生。不加入Ni，体心立方结构稳定，此时为铁素体

45、不锈钢。,- 42 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,For many applications not requiring the high corrosion resistant of austenitic stainless steels，these lower alloy(and less expensive) ferritic stainless steels are quite serviceable Serviceable有用的, 耐用的,由于很多应用场合不要求奥氏体不锈钢那样的抗腐蚀性能，那些低合金（或低价格的）铁素体不锈钢就

46、可满足要求。,- 43 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,A rapid quench heat treatment discussed later allows the formation of a more complex body centered tetragonal crystal structure called martensite . This crystal structure yields high strength and low ductilityAs a result，this martensitic stainle

47、ss steels are excellent for applications such as cutlery and springs quench淬火 cutlery刀具,热处理时快速淬火可形成更复杂的体心四角晶格结构的马氏体组织，该晶格结构强度高塑性差。因此马氏体不锈钢用于刀具和弹簧时非常好。,- 44 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,Precipitation hardening is another heat treatment Essentially，it involves producing a multiphase micr

48、ostructure from a single one. The result is increased resistance to dislocation motion and，thereby，great strength of hardness. Precipitation hardening stainless steels can be found in applications such as corrosion resistant structural members.,沉淀强化是另外一种热处理，实际上，它主要是从单一相生成多相组织。这会增加位错运动时的抗力，继而提高强度和硬度。

49、沉淀强化不锈钢主要应用于抗腐蚀的结构件。,- 45 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,Tool steels are used for cutting，forming or otherwise shaping another material. Plain carbon steel can also be tool steelFor shaping operations that are not too demanding，such a material is adequate. In fact, tool steels were histo

50、rically of the plain carbon variety until the mid-nineteenth century Adequate适当的，合适的，足够的，充分的。,工具钢主要应用于切削、成形或使其他材料成型（的场合）。普通碳钢也可作为工具钢。因为成型操作过程中没有太多要求，这一材料是足够（应用）的。事实上，直到19世纪中叶，工具钢都是各种普通碳钢。,- 46 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,Now high alloy additions are common . Their advantage is that th

51、ey can provide the necessary hardness with simple heat treatments and retain that hardness at higher operating temperature. The primary alloying elements used in these materials are tungsten，molybdenum and chromium. Tungsten钨 molybdenum钼,现在，工具钢中加入高合金也很普通。加入合金可以通过简单热处理提供所需硬度，获得高温工作时的硬度。这些材料中加入的主要元素为钨

52、、钼、铬。,- 47 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,The term superalloy refers to a broad class of metals with especially high strength at elevated temperature(even above 1000)Many stainless steels serve a dual role as heat resistant alloysExcept iron based superalloys，there are also cobalt and ni

53、ckel based alloys .,超合金一词特指高温(至少1000以上)下具有高强度的一大类钢。许多不锈钢也是耐热钢。除了铁基超合金，还有钴基和镍基合金。,- 48 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,Most superalloys contain chromium additions for oxidation and corrosion resistanceThese materials are expensive and, in some case，extremely soBut the increasingly severe r

54、equirements of modem technology are justifying such costs,大多数超合金含有铬以抗氧化和抗腐蚀。这些材料比较贵，有时特别贵。但是现代技术要求越来越严格，这样的价格也比较合理。,- 49 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,Between 1950 and 1980，the use of superalloys in aircraft turbojet engines rose from 10to 50by weight .At this point, our discussion of s

55、teels has taken us into closely to non-ferrous alloys. Before going on to the general area of all other nonferrous alloysWe must discuss the traditional and important ferrous system，the cast irons,在1950到1980的30年间，飞机涡轮喷气发动机中所用的超合金从10上升到50(重量百分比)。合金含量达50时，我们的讨论就接近非铁合金了。但在对非铁合金有个大致了解前，我们必须了解另一种传统且重要的铁铸铁。,- 50 -,CHAPTER 1 MATERIALS AND THEIR PROPERTIES,1.2.4 Cast Iron-铸铁 viscosity粘性，粘度 inferior低等的 magnesium镁 malleable可锻的；韧性的 shrinkage收缩 porosity孔；多孔性 Spheroidal 球状的；椭球体的 Nodular 节结状的；榴状,crystalline fracture surfa