机械制造专业英语--课后答案(部分)

专业英语翻译一stressandstrain（应力与应变）1thefundamentalconcepts基本概念crosssection横截面theinternalstressesproducedinthebar杆的内应力continuousdistributionofhydrostaticpressure流体静压力thetensileload拉伸载荷auniformdistributionoverthecrosssection在横截面均匀分布arbitrarycross-sectionalshape任意截面形状tensilestresses拉应力compressivestresses压应力anormalstress正应力throughthecentroidofthecrosssectionalarea通过横截面形心theuniformstresscondition压力均匀分布thestressdistributionattheendsofthebar杆末端应力分布highlocalizedstresses高度应力集中anaxiallyloadedbar轴向载荷杆件atensilestrain拉应变anelongationorstretchingofthematerial材料拉伸acompressivestrain压应变theratiooftwolengths两个长度的比值purelystaticalandgeometricalconsiderations从纯静态以及几何角度考虑1.Thatbranchofscientificanalysiswhichmotions,timesandforcesiscalledmechanicsandismadeupoftwoparts,staticsanddynamics.研究位移、时间和力运动乘力是科学分析法的一个分支，被称作力学，力学由两大部分组成，静力学和动力学。2.Forexample,iftheforceoperatingonasleevebearingbecomestoohigh,itwillsqueezeouttheoilfilmandcausemetal-to-metalcontact,overheatingandrapidfailureofthebearing.例如：如果止推轴承上的作用力过大的话，会挤出油膜，引起金属和金属之间的相互接触，轴承将过热而迅速失效。3.Ourintuitiveconceptofforceincludessuchideasasplaceofapplication,direction,andmagnitude,andthesearecalledthecharacteristicsofaforce.力的直观概念包括力的作用点、大小、方向，这些被称为力的三要素。4.Allbodiesareeitherelasticorplasticandwillbedeformedifacteduponbyforces.Whenthedeformationofsuchbodiesissmall,theyarefrequentlyassumedtoberigid,i.e.,incapableofdeformation,inordertosimplifytheanalysis.所有的物体既可以是弹性的也可以是塑性的，如果受到力的作用就产生变形。当变形很小的时候它们被假设成刚体，也就是不产生变形。5.Therigid-bodyassumptioncannotbeusedininternalstressesandstrainsduetotheappliedforcestobeanalyzed.Thusweconsiderthebodytobecapableofdeforming.刚体假设不能应用于内应力和内应变的分析，所以在实际力的分析时，要考虑物体的形变。6.Ifalltheforcesactingonaparticlearebalanced,theparticlewilleitherremainatrestorwillcontinuetomoveinastraightlineatauniformvelocity.如果作用在质点上所有的力是平衡的，质点将会保持静止或做做匀速直线运动。21)themainmanifestationsofcapacity主要的表现能力2)themaximumunitload（stress）最大单位载荷（应力）3）stress-straindiagram应力—应变图4）thesimpletensiletest简单的拉伸试验5）thepercentageelongationatrupture断裂伸长率6）theendsoftensilespecimens拉伸试样的两端7）permanentdeformation永久变形8）theresultingload-displacementcurve由此产生的载荷位移曲线9）asubstantialyieldingofthematerial大量产生的物质10）yieldpoint屈服点11)thetransitionfromelastictoplasticbehavior从弹性到塑性的过度12）materialpropertytable材料属性表13）plasticdeformation塑性变形14）aspecifiedstandardlengthofthespecimen指定的 标准 excel标准偏差excel标准偏差函数exl标准差函数国标检验抽样标准表免费下载红头文件格式标准下载 式样长度15）atthemomentofrupture此刻的破裂16）shortcylindricalspecimens短圆柱标本17）ductilematerials韧性材料18）highstressconcentration高应力集中19）ultimatetensilestrength极限抗拉强度20）strainhardeningzone应变硬化区1)Atensiletestconsistsofslowlypullingasampleofmaterialwithatensileloaduntilitbreaks.Theendsoftensilespecimensareusuallyenlargedtoprovideextraareaforgrippingandtoavoidhavingthesamplebreakwhereitisbeinggripped.拉伸试验包括慢慢加载拉伸载荷直到断裂，拉伸试件两端加粗为了提供装夹区域和避免试件断裂。2）Theusualmannerofconductingthetestistodeformthespecimenataconstantspeed.Forexample,intheUniversaltestingmachines,themotionbetweenthefixedandmovingcrossheadscanbecontrolledataconstantspeed.通常进行试验的方法就是使试件以恒定速度发生变形。例如，在万能拉伸试验机上，固定端和移动的十字滑块之间的变形是以恒定速度进行的。3）Theloadthatmustbeappliedtoenforcethisdisplacementratevariesasthetestproceeds.ThisloadFmaybedividedbythecross-sectionalareaAtoobtainthestressinthespecimenatanytimeduringthetest.随着实验的进行，用来产生位移的载荷是随位移的变化而变化。在实验中，载荷F除以横截面积A可以得到任意时刻点的应力。4）HoweveractualmeasurementofΔLispreferablewhereThisisfeasible.Stressandstrainbasedontheinitial(undeformed)dimensions,AiandLi,arecalledengineeringStressandstrain.然而，在可行的位置的ΔL的实际测量是更可取的，基于原始尺寸Ai和Li的应力和应变称为工程应力和工程应变。5)Ductileandbrittlematerialsbehavedifferentlyincompressiontestaswell.ThecompressiontestisconductedonshortCylindricalspecimensplacedbetweenparallelplates.塑性和脆性材料在压缩试验中表现的特性是不相同的。压缩试验是把短圆柱形试件放在两平行平板之间进行的6）Thecompressiontestdiagramforthesematerialsretains.Thequalitativefeaturesofthetensiontestdiagram.Theultimatecompressivestrengthofabrittleofabrittlematerialisdeterminedinthesamewayasintension.材料压缩试验图保持了拉伸试验图性能上的特征。脆性材料的最大压缩强度与最大拉伸强度得到的方法相同。第三单元Virtuallyallmachinescontainshafts.Themostcommonshapeforshaftsiscircularandthecrosssectioncanbeeithersolidorhollow(hollowshaftscanresultinweightsavings).几乎所有的机器都有轴，最常用的外形是圆形的，横截面是空心的或实心的圆形截面（空心轴可以减少重量）。Ashaftmusthaveadequatetorsionalstrengthtotransmittorqueandnotbeoverstressed.Itmustalsobetorsionallystillenoughsothatonemountedcomponentdoesnotdeviateexcessivelyfromitsoriginalangularpositionrelativetoasecondcomponentmountedonthesameshaft.一个轴必须有足够的扭转强度来传递扭矩而不会破坏，同样也必须有足够的扭转刚度，这样安装轴就不能过度偏离相对于安装在同一轴上第二个零件的原始位置。Shaftsaremountedonbearingsandtransmitpowerthroughsuchdevicesasgears,pulleys,camsandclutches.Thesedevicesintroduceforceswhichattempttobendtheshaft;hence,theshaftmustberigidenoughtopreventoverloadingofthesupportingbearings.轴安装在轴承上通过齿轮，滑轮，凸轮和离合器这些装置传递力。这些装置可以产生使轴弯曲的力，所以轴必修有足够的刚性防止支撑轴承的过载。Inaddition,theshaftmustbeabletosustainacombinationofbendingandtorsionandbending.另外，轴必须能承载弯扭组合的载荷，因此，这样就必须考虑弯扭组合的等效载荷。Componentssuchasgearsandpulleysaremountedonshaftsbymeansofkey.Thedesignofthekeyandthecorrespondingkeywayintheshaftmustbeproperlyevaluated.齿轮和滑轮构件是用键的方式连接在轴上的，键和对应的键槽的设计必须进行估算。Anotherimportantaspectofshaftdesignisthemethodofdirectlyconnectingoneshafttoanother.Thisisaccomplishedbydevicessuchasrigidandflexiblecouplings.轴设计的另一个重要方面是直接连接两轴，通过刚性和柔性的联轴器装置来实现。41)herringbonegears人字形齿轮2）spiralgears螺旋齿轮3）wormgears蜗轮4)bevelgears（圆）锥齿轮，伞齿轮5）hypoidgears准双曲面齿轮6）sizesofspur-gearteeth轮齿尺寸7)theautomotiverearaxledrives汽车后桥驱动8)rack-and-piniondrives齿条和小齿轮驱动9)diametralpitch径节10)pitchcircle节圆11)thetangencypoint切点12)pressureangles压力角13)aninvolutecurve渐开线曲线14)theradialdistant径向距离15)atrightangles成直角16)theaveragenumberofteethincontact平均啮合齿数17)thereciprocalofthediametralpitch径节的导数18)tochangeinchestomillimeters将英寸改为毫米19)alineperpendiculartothecenterlines垂直于中心线的线20)centerdistancebetweentwomeshedgears两个互相啮合齿轮的中心距离1)Pressureanglesforspurgearsareusually14.5or20degress,althoughothervaluescanbeused.Meshinggearsmusthavethesamepressureangles.译文：虽然直齿圆柱齿轮的压力角可以取很多其他值，但通常大多是在14.5至20度之间。互相啮合齿轮的压力角必须相同。2)Theshapeofthespacebetweengearteethiscomplexandvarieswiththenumberofteethonthegearaswellastoothmodule,somostgearmanufacturingmethodsgeneratethetoothflankinsteadofforming.译文：由于齿轮齿数以及齿形的不同，齿轮齿侧间隙的形状也是复杂多样的，所以大多数齿轮的制造方法是范成发而不是成型法。3)Wormgearsareusedwherehighratiosaredesiredandwheretheshaftsarenointersectingandatrightangles.译文：蜗轮蜗杆常用于那些要求高传动比同时两根轴不交叉但成直角的场合。4)Ithasthegreatadvantagethatthecuttingtoolisasimplerackwith(nearly)straightsidedteethwhichcaneasilybegroundaccurately.译文：一个很大的优势在于刀具是在一个简单的齿条几乎可以直接准确地支起被磨损的轮齿。5)Modernshaperscuttingcargearscanrunat2000cuttingperminute.Theshapeofthecutterisroughlythesameasaninvolutegearbutthetipsoftheteetharerounded.译文：现代牛头刨床削减汽车齿轮可以运行在每分钟2000。刀具的形状大致与渐开线齿轮的圆形轮齿相同。6)Bevelgearsareoftenusedwhentwoshaftsareatrightanglestoeachotherandtheircentenlineextensionsintersect;however,somebevelgearsareatanglesotherthan90degrees.译文：锥齿轮常用于两轴互相垂直且它们中心线的延长线相交的场合下。可是，有些锥齿轮的轴线并非互相垂直。51.platecams盘形凸轮2.cylindricalcams圆柱凸轮3.thecamassembliesinautomaticrecordplayers录音机上的凸轮组件4.camprofiles凸轮轮廓5.makeafull-scaletemplate制造一个实尺样板6.inthecourseofseveralrevolutionsofthecam在凸轮转几转的过程中7.atangentialplatetemplate切向盘形凸轮8.atranslationcam移动凸轮9.thegrooveintheperipheryofthecam凸轮表面上的槽10.aguidedverticalreciprocatedfollower纵向做往复运动的从动件11.aconstant-diametercam等径凸轮12.automaticwashingmachines自动洗衣机13.afacecam面凸轮14.theedgeofapivotedfollower摆动从动件的边缘15.areciprocatingknife-edgedfollower一个做往复运动的刃口式从动件16.miniaturesnap-actionelectricalswitches微型速动电开关17.apivotedflat-facedfollower一个转动的平面从动件18.airpilotvalues空气试点值19.theabruptchangeincamprofile凸轮轮廓的突变20.aScotchyokemechanism苏格兰约克机构1.Thepurposeofanycamistoproduceadisplacementofitsfollowerisofenusedtoproduceadditionaldisplacementinanotherlocation.使用凸轮的目的是使其从动件产生位移，次级从动件常用来在另一位置产生附加位移2.TherelativeverticalpositionofpointAwithrespecttoBneedstoberaisedifthereactionvalueatBisexcessive.如果B点的值超量，点A相对于B的垂直位置就要升高3.Ingeneral,thefollowerisconsideredtobethepartthatcomesincontactwiththecamprofile.However,whenasecondaryfollowerisused,themotionofthesecondaryfollowerisdicatatedbythatoftheprimaryfollower.总的来说，从动件是与凸轮轮廓相接触的零件。然而，当用次级从动件时，次级从动件的运动就需要通过主要从动件来实现4.Thesimplesttypeoffolloweristhereciprocatingtypethatmerelymovesupanddown(orinandout)withtherotationofthecam;thecenterlinecanbeeithercollinearwiththecamcenterlineoroffsetfromit.最简单的从动件是随着凸轮的转动而仅作上下（或进出）往复运动的从动件，其中心线可与凸轮中心线共线，也可与之偏离。5.Fastenersaredeviceswhichpermitoneparttobejoinedtoasecondpartand,hence,theyareinvolvedinalmostalldesigns.紧固件是一种可以连接两个零件的部件，因此他们几乎在所有设计中都被涉及到。6.Springsaremechanicalmemberswhicharedesignedtogivearelativelylargeamountofelasticdeflectionundertheactionofanexternallyappliedload.弹簧是一种被设计为在外部负载的作用下能发生相对大量弹性变形的机械部件。61)adevelopinganddemandingindustry产业的发展与要求2)propellershaft螺旋轴3)suspensioncomponents悬挂部件4)aslidingsplinedtypeofjoint滑动式花键5)towrearaxleshafts双转向轴轴6)tomeshwithalargerbevelgear与较大的锥齿轮啮合7)theuniversaljoints万向节8)asteeringwheel转向盘9)unevennessofroadsurface路面的不平整度10)thetransverselineofthetheaxleshafts该轴的横向线11)tocauseexcessivetyrewear使轮胎磨损过度12)theexactlysimilardiameter完全相似的直径13)quarter-ellipticleafsprings四分之一椭圆钢板弹簧片14)thetransmissionofshock震动的传播15)roadsurfacevariation路面的变化16)thefinal-drivegears最终传动齿轮17)theprecisealignmentofshaft轴的精确定位18)arotatingdrum一个旋转的筒鼓19)ahandlever手柄20)belockedintheoneposition被锁定在一个位置1)Thelubricationsystemprovidesaconstantflowoffilteredoiltoallmovingpartsoftheengine.Thesystemconsistsofanoilpantostoretheoil,apumptocirculateit,afiltertoremovesolidabrasiveparticles,andanoilgaugeorlightinthedriver’scompartmentforcheckingpurposes.译:润滑系统提供了源源不断的过滤油给发动机的各个运动部件，该系统由一个油箱来储存油，一个泵来输送油，一个过滤装置除去固体磨料颗粒，并且在驾驶室里有个油压表或者指示灯来方便驾驶员检查油量是否充足。2)Thedrivelineconsistsofmechanismsandunitswhichtransmittorquefromtheenginetothedrivewheelsandchangetorqueandrpminmagnitudeanddirection.译:传动系包括机制和单位，它将扭矩传送到驱动轮并改变转矩和转速的大小和方向。3)Ithasbeenseenthatiftheconditionsarenotveryabnormal,sufficientamountoftyresliptakingplaceunderrunningconditionswouldreleasethesestressescompletely.译:可以看到，如果运行状况不是很正常，轮胎在行驶的情况下发生足够的滑移，这些压力就会被完全释放出来。4)Mucheffortisrequiredtocranktheengineduringstarting,sinceitisnecessarytoovercomefrictioninthemovingenginecomponentsandtheresistanceofferedbythechargebeingcompressed.译:发动机开始运行需要经过许多努力，比如必须要克服发动机运动部件之间的阻力和内部装置间的压力。5)Theclutchisafrictiondeviceusedtoconnectanddisconnectadrivingforcefromadrivenmember.Itisusedinconjunctionwithanengineflywheeltoprovidesmo0thengagementanddisengagementoftheengineandmanualtransmission.译:离合器是一个将驱动力从驱动机构连接或者断开的摩擦装置，它由人力操控连接发动机的飞轮来提供平滑的连接与分离。6)Thedifferentialisagearsystemthattransferspowerfromthedriveshafttothedrivingaxles.Italsopermitsonedrivingwheeltoturnfasterthantheothertopreventskiddingandscuffingoftiresonturns.译:差速器是一个将动力从主动轴传送到驱动轴的齿轮装置，它的存在可以允许一个驱动轮的速度比另一个更快从而避免轮胎在转动时发生打滑和擦伤。71.Greensand型砂2.Pourmoltenmetalintoapreparedcavity将熔融的金属倒入型腔中3.Morestableandrefractorysands耐熔砂4.Beusedtoproduceintricatemolds用来制作复杂铸型5.Bothferrousandnonferrousmaterials黑色及有色金属6.Partingpowder分形砂7.Berammed夯实8.Patterndraft拔模斜度9.Sprues,runnersandgates直浇道，横浇道和内浇口10.Apouringbasin外浇口11.Tomakeupforshrinkagelosses用于弥补收缩损失12.Thecopeandthedrag上沙箱和下沙箱13.Someorganicbondingmaterials一些有机黏合材料14.Grossshrinkage缩孔15.Abottom-pouringladle底部浇注铁水包16.Therateofsolidification凝固速率17.Toaffectthedegreeofliquidcontraction影响液体收缩的程度18.Columnargrowthpresentatthemoldwall铸型中针状物的成长19.Thefeedingcharacteristicsoftheriseringsystem冒口的补缩特征20.Unwantedmetalprotrusions多余的金属突起1.Thefirststageintheproductionofsandcastingmustbethedesignandmanufactureofasuitablepattern.Castingpatternhastobemadelargerthanthefinishedcastingsizetoallowfortheshrinkagethattakesplaceduringsolidificationandcooling.在型砂铸造生产中，第一阶段是必须设计和制造合适的模型，考虑到铸件在凝固和冷却期间产生的收缩，铸件模型的尺寸要比铸件的尺寸大。2.Ifahollowcastingistobemadethepatternwillincludeextensionpiecessothatspacestoacceptthesandcorearemoldedintothesand,Theseadditionalspacesinthemoldaretermedcoreprints.如果铸造空心铸件时，模型上包含伸长杆便于在砂中放置砂芯的空间称为型芯座3.Sandmoldsfortheproductionofsmallandmedium-sizedcastingsaremadeinamoldingbox.Themoldismadeintwoormorepartsinorderthatthepatternmayberemoved.中小型尺寸的铸件砂型是在一个砂箱中制造，砂型由两部分或更多部分组成，以利于模型的顺利取出。4.Thisprocessoffillingandrammingmaybedonebyhandbutmoldproductionisautomatedinalargefoundrywiththemoldboxesmovingalongaconveyor,firstlytobefilledwithsandfromhoppersandthentopassundermechanicalhammersforramming.填充和夯实的过程可以手工完成，但在大型铸造中砂型的制造是自动完成的，砂箱随着传送带移动，首先被料斗中的砂子填满，然后通过机械锤被打实。5.Therisersshouldcoincidewiththehighestpointsofthemoldcavitysothatthedisplacedaircanreadilyescapefromthemold.Thesizesofrisersshouldbesuchthatthemetalinthemdoesnotfreezetoorapidly.冒口应该与型腔的最高点相连接，使得进入的空气可以容易的从模型中溢出，冒口的尺寸应该足够大使模型中金属不会太快凝固。6.Whenthemetalthathasbeenpouredintoasandmoldhasfullysolidified,themoldisbrokenandthecastingisremoved.Thecastingstillhastherunnerandrisersattachedtoitandtherewillbesandadheringtoportionsofthesurface.当熔融的金属被倾倒到砂型内并充分凝固以后，砂型将被打破取出铸件，铸件上依然带有横浇口和冒口并且依然有砂子粘在表面。81).bulkdeformationdfmetals金属体积成形2).forging,rolling,orextruding锻造、轧制、挤压3).plasticdeformation塑性变形4).impactblows影响冲击5).therecrystallizationpointofthemetal金属的再结晶点6).hotworkingandcoldworking热加工和冷加工7).bettersurfacefinish更好的表面光洁度8).hammerforging锤锻造9).strikingthehotmetal热金属的10).aslowsqueezingacting缓慢的挤压作用11).opendiesangcloseddies开模和封闭模具12).bevelgearswithstraightorhelicalteeth圆锥齿轮跟直齿轮或者螺旋齿轮的齿13).impressiondies型腔模具14).eachofdiecavities每个模腔15).massproduction大规模生产16).ahomogeneouscircumferentialgrainflow均匀圆周颗粒流17).thethree-dimensionaldescription三维描述18)putersimulation计算机模拟19).hydraulicpresses液压机20).berough-andfinished-machined是粗糙的并且经过机加工完成的1.Forgingmeanstheshapingofmetalbyaseriesofhammerblows,orbyslowapplicationofpressure.Thesimplestexampleisablacksmith'sforgingofahotpieceofmetalbyhammeringthework-pieceonananvil.锻造是指通过一系列的捶打或缓慢的挤压使金属成形的过程。最简单的例子就是铁匠通过在铁砧上捶打一块热的金属来制造工件。2.Heavysmith'sforgingisfundamentallysimilar,differingonlyinthescaleoftheoperation,Thework-piecemaybeaningotof100tonsandthedeformingforceprovidedbyamassiveforginghammer,butthewholeprocessiscontrolledbythemastersmith,whodecideseachtimewhere,andwithwhatforce,theblowshouldtakeplace.铁匠们沉重的锻造工作基本上是相似的,不同的地方只是在于锻造的规模,工件可能是一个100吨的金属锭，并且金属锭变形所需要的力是通过一把大规模的锻造锤提供,但是整个过程都是由主铁匠控制,决定每一次捶打在什么地方，用什么力量以及是否需要冷却。3.Forgingoperationsmaybecarriedoutusingeitherforginghammersorforgingpresses.Withapress,asopposedtoahammer,pressureisslowlyappliedandplasticdeformationtendstooccurfairlyuniformlythroughoutthemeterial.锻造时可以用锻造锤，也可以用锻造压力机。与锻造锤不同,通过锻造压力机锻造时，压力被缓慢的施加，塑性变形往往会相当均匀地贯穿整个材料。4.Forginghammersareoftwobasictypeswiththelargehammereitherdroppingontothework-pieceacceleratedbygravityaloneor,asinthesteamhammer,acceleratedbybothgravityandsteampressure.大型锻造锤有两种基本类型，一种捶打工件仅仅靠重力使大锤加速,另一种靠重力和蒸汽加速使大锤加速，如蒸汽锤。5.Smith'soropen-dieforgingisusedformakingverylargeforgingsorwhenthenumberofforgingsofaparticulardesignissmall.Open-dieforgingisalsousedtopreformmetalpriortofinalshapingbymeansofclosed-dieforging.锤锻或开模锻适用于制造非常大锻件，或少量特殊设计锻件。开模锻还可以用于金属闭模锻之前的粗加工。6.Closed-dieforginginvolvestheuseofaccuratelymachineddieblocks.Thecapitalcostofapairofdieblocksishigh,butthisisallowablewhenitisrequiredtomakeforgingstoclosedimensionaltolerancesandinlargequantity,aswouldbethecasefor,say,connectingrodsfirtheengineofapopularcar.闭模锻涉及到精确加工模块的使用。一对模具块的成本很高,但当锻件尺寸公差要求很高，数量很大情况下，闭模锻是适用的91)carryinghigh-amperagecurrent带有高电流2)theelectrodeandthework-piece电极和工件3)theweldpool熔池4)acolumnofionizedgascalledplasma等离子区的柱状电离气体5)theoxidesandnitrides氮氧化物6）thepositiveions正离子7)deleterioussubstances有害物质8）thenewlysolidifiedmetal新凝固金属9)inoverheadwelding仰焊10）currentdensity电流密度11）depositionrate沉积速率12）anunbalancedmagneticfield不平衡磁场13）arcblow电弧偏吹14）theelectrodecoating焊条涂层15）inoverheadposition仰焊场合16）thecoolingrateofthedepositedmetal焊缝金属的冷却速率17）amorehomogeneousmicrostructure更均匀的显微（结构）18）asoomthflowofmoltenmetal熔融金属的平稳流动19）cellulosic-coatedelectrodes纤维涂层的焊条20）perpendiculartothecurrentpath垂直于电流通道1）Arcweldinginoneformoranotheristhemostwidelyusedformofwelding.Theelectricalsupplyislowvoltagebuthighamperageandmaybeeitheralternatingordirect.电弧焊在一种或另一种形式是应用最广泛的焊接形式。电源供应低电压，但是大电流,可以是交流或直流。2)Theearliestformsofarcweldingusedcarbonelectrodes.Butnowadaysthearcisstruckbetweenametalelectrodeandthework-piece.Theelectrodemayeitherbeoftungstenorbeaconsumablemetalelectrodethatmelts,actingasasourceoffillermetal.最早的形式的电弧焊用碳电极。但如今弧金属电极和工件之间。电极可以是钨或可熔化,作为填充金属供源的消耗性金属电极。3)Analternating-currentarcisbrokenandre-establishedateachhalfcycleandthisleadstoarcinstabilityalthoughtheuseofarc-establishingagentsinthefluxcoatingofelectrodewirescanovercomethisproblem.交流电弧被打破,重新建立在每个半周期和这导致电弧不稳定虽然在电极布线焊剂涂层使用电弧建立剂可以克服这个问题。4)Uncoatedweldingrodscanbeusedforarcwilding,butitismoreusualtouseflux-coatedelectrodes.Whensteelsareweldedusinguncoatedelectrodes,oxidesandnitridescanformandremainintheweldwithaconsequentlossoftoughness.裸焊接棒可用于电弧野生植物,但更通常使用焊剂涂层电极。钢焊接使用裸电极时,氧化物和氮化物可以形成并保持在焊缝的韧性。5)Flux-coatedelectrodesarewidelyused.Thecompositionofthecoatingiscomplexandavarietyofdifferentcoatingsareusedtocaterfordifferenttypesofweldingapplication.焊剂涂层电极被广泛使用。涂料的组成很复杂,各种不同的涂料用于满足不同类型的焊接应用。6)Inthiscasetheelectronflowisfromelectrodetowork-piece.Aconcentratedarcissuesfromtheelectrodetipandheatingofthework-pieceislargelyconfinedtotheverysmallareabeneaththeelectrode.在这种情况下,电子流动从电极到工件。集中弧电极头和工件的加热问题主要局限在极小的区域下的电极。10101)plaincarbonsteel普通碳素钢2)carboncontent含碳量3)lowcarbonsteel低碳钢4)mediumcarbonsteel中碳钢5)highcarbonsteel高碳钢6)becoldworked冷加工7)beheattreated热处理8)contain20pointofcarbon碳含量0.2%9)inthehot-rolledcondition热轧状态10)heat-treat-hardenedplaincarbonsteel热处理淬硬的普通碳素钢11)free-machiningsteels易切削钢12)hotshort热脆13)coldshortness冷脆性、低温脆性14)theisothermaltransformationcurves等温转变曲线15)grainrefinement晶粒细化16)stainlesssteel不锈钢17)AISIsteelsAISI钢18)iron-carbonequilibriumdiagram铁碳合金平衡相图19)toolanddiesteels工具钢和模具钢20)highcorrosionandchemicalresistance耐高腐蚀能力和抗化学作用1)Insimpleterms,aplaincarbonsteelmaybesaidtobeanalloyofironandcarboncontaininglessthan1.7%carbon.Inpractice,however,thesesteelsrarelycontainmorethan1.4%carbonandotherelementsarealsopresent,eitherasdeliberateadditions(e.g.manganese)orasimpurities(e.g.sulphurandphosphorus).简单来说，普通碳素钢被认为是一种含碳量少于1.7%的铁碳合金。然而，事实上，这些钢的含碳量很少超过1.4%，同时还含有一些其他元素，例如一些额外添加物（如锰）或杂质（如硫和磷）2)Inthemanufactureofmaterial,completedeoxiadationisnotcarriedoutanditismadeasrimmingsteel.Itisproducedashotandcoldworkedsheet,strip,rod,wire,andtube,andisavailableinthehot-workedorprocessannealedcondition.在材料的加工过程中，不完全脱氧还原的被加工成沸腾钢。它通过热加工或冷加工被制成板材、带材、棒材、线材和管材，这些也可在热加工和退火条件下获得。3)Thestrengthandhardnessofthesesteelislow,butahardsurfacecanbeobtainedbycarburizinginordertocombineawear-resistantsurfacewithtoughcoreproperties.这类钢的强度和硬度很低，但能通过渗碳作用表面硬化，他兼顾了表面耐磨和内部韧性较好的特点。4)Asthecarboncontentisraisedabove0.2%,thestrengthincreasesintotherangerequiredforconstructionalpurpose,buttheductilitydecreases.Thefabricationqualities(workingandweldingcharacteristics)ofthismaterialareverygood.当含碳量上升超过0.2%时，需求范围内的结构用途的强度增加，但是延展性会下降。材料的制造质量（承载性和焊接特性）会非常好。5)Mediumcarbonsteelsareoftenquenched-hardenedandfullytemperedtogivegoodstrengthwithmaximumtoughness,whicharethepropertiesrequiredofcomponentssuchasshafts,gearsandconnectingrods.中碳钢常被淬火和完全回火处理以赋予高的强度的同时拥有最大的韧性，这些特性都是像轴、齿轮和连杆这一类的零件所需要的。6)Highcarbonsteelsarequenchhardenedandlightlytemperedtogivehighhardnesswithonlylimitedtoughness.Materialinthisclassificationismainlyusedformakingfairlysmall,reactivelyinexpensivecuttingtoolssothatthegroupasawholeisknownascarbontoolsteel.高碳钢通过淬火和低温回火来给予高硬度的同时兼有一定的韧性。这类材料主要被用于加工相当小而可靠，并且廉价的切削工具，因此一般被称为碳素工具钢。111.allotoropicmaterials同素异晶体2.plainlowcarbonsteels普通低碳钢3.hypoeutectoidsteel亚共析钢4.normalizedsteel正火钢5.hypereutectoidsteel过共析钢6.eutectoidcomposition共析成分7.grainboundaries晶界8.ferritematrix铁素体基体9.about60℃abovetheAc1temperatureAc1温度以上大约60℃10.thenoseoftheI-Tcurve等温曲线鼻部11.coolingrate冷却温度12.quenchingmedia淬火介质13.thermalstress热应力14.thermalshock热冲击15.atemperedsteel回火钢16.temperbrittlement回火脆性17.inthetemperingordrawingprocedure回火时18.hardenedsteel淬硬钢19.fullannealing完全退火20.todissolveallthecementite溶解所有渗碳体1.Theprincipalkindsofheat-treatmentusedinpractice,whichdifferentlyaffectthestructureandproperities,andwhichareassignedtomeettherequirementsmadetothesemifabricatedmaterials(casting,forging,rolledstock,etc.）andfinishedarticles,are:(1)annealing;(2)normalizing;(3)hardeningand(4)tempering.在实践中用到的能对结构和性质有不同影响的，并被分配满足半成品材料（铸造，锻造，轧制成品等）的要求的热处理基本类型是：（1）退火；（2）正火；（3）硬化和（4）退火。2.Normalizingraisesthestrengthandhardnessofmedium-andhigh-carbonsteelsby10to15percentas