專業(yè)英語翻譯

1thefundamentalconcepts基本概念crosssection橫截面theinternalstressesproducedinthebar桿內(nèi)應(yīng)力continuousdistributionofhydrostaticpressure流體靜壓力thetensileload拉伸載荷auniformdistributionoverthecrosssection在橫截面均勻分布arbitrarycross-sectionalshape任意截面形狀tensilestresses拉應(yīng)力compressivestresses壓應(yīng)力anormalstress正應(yīng)力throughthecentroidofthecrosssectionalarea經(jīng)過橫截面形心theuniformstresscondition壓力均勻分布thestressdistributionattheendsofthebar桿末端應(yīng)力分布highlocalizedstresses高度應(yīng)力集中anaxiallyloadedbar軸向載荷桿件atensilestrain拉應(yīng)變anelongationorstretchingofthematerial材料拉伸acompressivestrain壓應(yīng)變theratiooftwolengths兩個(gè)長度比值purelystaticalandgeometricalconsiderations從純靜態(tài)以及幾何角度考慮1.Thatbranchofscientificanalysiswhichmotions,timesandforcesiscalledmechanicsandismadeupoftwoparts,staticsanddynamics.研究位移、時(shí)間和力運(yùn)動乘力是科學(xué)分析法一個(gè)分支，被稱作力學(xué)，力學(xué)由兩大部分組成，靜力學(xué)和動力學(xué)。2.Forexample,iftheforceoperatingonasleevebearingbecomestoohigh,itwillsqueezeouttheoilfilmandcausemetal-to-metalcontact,overheatingandrapidfailureofthebearing.比如：假如止推軸承上作用力過大話，會擠出油膜，引發(fā)金屬和金屬之間相互接觸，軸承將過熱而快速失效。3.Ourintuitiveconceptofforceincludessuchideasasplaceofapplication,direction,andmagnitude,andthesearecalledthecharacteristicsofaforce.力直觀概念包含力作用點(diǎn)、大小、方向，這些被稱為力三要素。4.Allbodiesareeitherelasticorplasticandwillbedeformedifacteduponbyforces.Whenthedeformationofsuchbodiesissmall,theyarefrequentlyassumedtoberigid,i.e.,incapableofdeformation,inordertosimplifytheanalysis.全部物體既能夠是彈性也能夠是塑性，假如受到力作用就產(chǎn)生變形。當(dāng)變形很小時(shí)候它們被假設(shè)成剛體，也就是不產(chǎn)生變形。5.Therigid-bodyassumptioncannotbeusedininternalstressesandstrainsduetotheappliedforcestobeanalyzed.Thusweconsiderthebodytobecapableofdeforming.剛體假設(shè)不能應(yīng)用于內(nèi)應(yīng)力和內(nèi)應(yīng)變分析，所以在實(shí)際力分析時(shí)，要考慮物體形變。6.Ifalltheforcesactingonaparticlearebalanced,theparticlewilleitherremainatrestorwillcontinuetomoveinastraightlineatauniformvelocity.假如作用在質(zhì)點(diǎn)上全部力是平衡，質(zhì)點(diǎn)將會保持靜止或做做勻速直線運(yùn)動。21)themainmanifestationsofcapacity主要表現(xiàn)能力2)themaximumunitload（stress）最大單位載荷（應(yīng)力）3）stress-straindiagram應(yīng)力—應(yīng)變圖4）thesimpletensiletest簡單拉伸試驗(yàn)5）thepercentageelongationatrupture斷裂伸長率6）theendsoftensilespecimens拉伸試樣兩端7）permanentdeformation永久變形8）theresultingload-displacementcurve由此產(chǎn)生載荷位移曲線9）asubstantialyieldingofthematerial大量產(chǎn)生物質(zhì)10）yieldpoint屈服點(diǎn)11)thetransitionfromelastictoplasticbehavior從彈性到塑性過分12）materialpropertytable材料屬性表13）plasticdeformation塑性變形14）aspecifiedstandardlengthofthespecimen指定標(biāo)準(zhǔn)式樣長度15）atthemomentofrupture此刻破裂16）shortcylindricalspecimens短圓柱標(biāo)本17）ductilematerials韌性材料18）highstressconcentration高應(yīng)力集中19）ultimatetensilestrength極限抗拉強(qiáng)度20）strainhardeningzone應(yīng)變硬化區(qū)A

tensile

test

consists

of

slowly

pulling

a

sample

of

material

with

a

tensile

load

until

it

breaks.

The

ends

of

tensile

specimens

are

usually

enlarged

to

provide

extra

area

for

gripping

and

to

avoid

having

the

sample

break

where

it

is

being

gripped.拉伸試驗(yàn)包含慢慢加載拉伸載荷直到斷裂，拉伸試件兩端加粗為了提供裝夾區(qū)域和防止試件斷裂。Theusualmannerofconductingthe

test

is

todeformthespecimenataconstantspeed.Forexample,intheUniversaltestingmachines,the

motionbetweenthefixedandmovingcrossheadscan

becontrolledataconstantspeed.

通常進(jìn)行試驗(yàn)方法就是使試件以恒定速度發(fā)生變形。比如，在萬能拉伸試驗(yàn)機(jī)上，固定端和移動十字滑塊之間變形是以恒定速度進(jìn)行。Theloadthatmustbeappliedtoenforcethisdisplacementratevariesasthetestproceeds.ThisloadFmaybedividedbythecross-sectionalareaAtoobtainthestressinthespecimenatanytimeduringthetest.伴隨試驗(yàn)進(jìn)行，用來產(chǎn)生位移載荷是隨位移改變而變化。在試驗(yàn)中，載荷F除以橫截面積A能夠得到任意時(shí)刻點(diǎn)應(yīng)力。4）HoweveractualmeasurementofΔLis

preferable

where

Thisisfeasible.Stressandstrainbasedon

theinitial

(undeformed)dimensions,AiandLi,arecalledengineeringStressandstrain.然而，在可行位置ΔL實(shí)際測量是更可取，基于原始尺寸Ai和Li應(yīng)力和應(yīng)變稱為工程應(yīng)力和工程應(yīng)變。5)Ductileandbrittlematerialsbehavedifferentlyincompressiontestaswell.ThecompressiontestisconductedonshortCylindricalspecimensplacedbetweenparallelplates.塑性和脆性材料在壓縮試驗(yàn)中表現(xiàn)特征是不相同。壓縮試驗(yàn)是把短圓柱形試件放在兩平行平板之間進(jìn)行Thecompressiontestdiagramfor

these

materialsretains.Thequalitativefeaturesofthetensiontestdiagram.Theultimatecompressivestrengthofabrittleofabrittlematerialisdeterminedinthesameway

as

in

tension.材料壓縮試驗(yàn)圖保持了拉伸試驗(yàn)圖性能上特征。脆性材料最大壓縮強(qiáng)度與最大拉伸強(qiáng)度得到方法相同。41)herringbonegears人字形齒輪2）spiralgears螺旋齒輪3）wormgears蝸輪4)bevelgears（圓）錐齒輪，傘齒輪5）hypoidgears準(zhǔn)雙曲面齒輪6）sizesofspur-gearteeth輪齒尺寸7)theautomotiverearaxledrives汽車后橋驅(qū)動8)rack-and-piniondrives齒條和小齒輪驅(qū)動9)diametralpitch徑節(jié)10)pitchcircle節(jié)圓11)thetangencypoint切點(diǎn)12)pressureangles壓力角13)aninvolutecurve漸開線曲線14)theradialdistant徑向距離15)atrightangles成直角16)theaveragenumberofteethincontact平均嚙合齒數(shù)17)thereciprocalofthediametralpitch徑節(jié)導(dǎo)數(shù)18)tochangeinchestomillimeters將英寸改為毫米19)alineperpendiculartothecenterlines垂直于中心線線20)centerdistancebetweentwomeshedgears兩個(gè)相互嚙合齒輪中心距離1)Pressureanglesforspurgearsareusually14.5or20degress,althoughothervaluescanbeused.Meshinggearsmusthavethesamepressureangles.譯文：即使直齒圓柱齒輪壓力角能夠取很多其余值，但通常大多是在14.5至20度之間。相互嚙合齒輪壓力角必須相同。2)Theshapeofthespacebetweengearteethiscomplexandvarieswiththenumberofteethonthegearaswellastoothmodule,somostgearmanufacturingmethodsgeneratethetoothflankinsteadofforming.譯文：因?yàn)辇X輪齒數(shù)以及齒形不一樣，齒輪齒側(cè)間隙形狀也是復(fù)雜多樣，所以大多數(shù)齒輪制造方法是范成發(fā)而不是成型法。3)Wormgearsareusedwherehighratiosaredesiredandwheretheshaftsarenointersectingandatrightangles.譯文：蝸輪蝸桿慣用于那些要求高傳動比同時(shí)兩根軸不交叉但成直角場所。4)Ithasthegreatadvantagethatthecuttingtoolisasimplerackwith(nearly)straightsidedteethwhichcaneasilybegroundaccurately.譯文：一個(gè)很大優(yōu)勢在于刀具是在一個(gè)簡單齒條幾乎能夠直接準(zhǔn)確地支起被磨損輪齒。5)Modernshaperscuttingcargearscanrunatcuttingperminute.Theshapeofthecutterisroughlythesameasaninvolutegearbutthetipsoftheteetharerounded.譯文：當(dāng)代牛頭刨床削減汽車齒輪能夠運(yùn)行在每分鐘。刀具形狀大致與漸開線齒輪圓形輪齒相同。6)Bevelgearsareoftenusedwhentwoshaftsareatrightanglestoeachotherandtheircentenlineextensionsintersect;however,somebevelgearsareatanglesotherthan90degrees.譯文：錐齒輪慣用于兩軸相互垂直且它們中心線延長線相交場所下。可是，有些錐齒輪軸線并非相互垂直。51.platecams盤形凸輪2.cylindricalcams圓柱凸輪3.thecamassembliesinautomaticrecordplayers錄音機(jī)上凸輪組件4.camprofiles凸輪輪廓5.makeafull-scaletemplate制造一個(gè)實(shí)尺樣板6.inthecourseofseveralrevolutionsofthecam在凸輪轉(zhuǎn)幾轉(zhuǎn)過程中7.atangentialplatetemplate切向盤形凸輪8.atranslationcam移動凸輪9.thegrooveintheperipheryofthecam凸輪表面上槽10.aguidedverticalreciprocatedfollower縱向做往復(fù)運(yùn)動從動件11.aconstant-diametercam等徑凸輪12.automaticwashingmachines自動洗衣機(jī)13.afacecam面凸輪14.theedgeofapivotedfollower擺動從動件邊緣15.areciprocatingknife-edgedfollower一個(gè)做往復(fù)運(yùn)動刃口式從動件16.miniaturesnap-actionelectricalswitches微型速動電開關(guān)17.apivotedflat-facedfollower一個(gè)轉(zhuǎn)動平面從動件18.airpilotvalues空氣試點(diǎn)值19.theabruptchangeincamprofile凸輪輪廓突變20.aScotchyokemechanism蘇格蘭約克機(jī)構(gòu)1.Thepurposeofanycamistoproduceadisplacementofitsfollowerisofenusedtoproduceadditionaldisplacementinanotherlocation.使用凸輪目標(biāo)是使其從動件產(chǎn)生位移，次級從動件慣用來在另一位置產(chǎn)生附加位移2.TherelativeverticalpositionofpointAwithrespecttoBneedstoberaisedifthereactionvalueatBisexcessive.假如B點(diǎn)值超量，點(diǎn)A相對于B垂直位置就要升高3.Ingeneral,thefollowerisconsideredtobethepartthatcomesincontactwiththecamprofile.However,whenasecondaryfollowerisused,themotionofthesecondaryfollowerisdicatatedbythatoftheprimaryfollower.總來說，從動件是與凸輪輪廓相接觸零件。然而，當(dāng)用次級從動件時(shí)，次級從動件運(yùn)動就需要經(jīng)過主要從動件來實(shí)現(xiàn)4.Thesimplesttypeoffolloweristhereciprocatingtypethatmerelymovesupanddown(orinandout)withtherotationofthecam;thecenterlinecanbeeithercollinearwiththecamcenterlineoroffsetfromit.最簡單從動件是伴隨凸輪轉(zhuǎn)動而僅作上下（或進(jìn)出）往復(fù)運(yùn)動從動件，其中心線可與凸輪中心線共線，也可與之偏離。5.Fastenersaredeviceswhichpermitoneparttobejoinedtoasecondpartand,hence,theyareinvolvedinalmostalldesigns.緊固件是一個(gè)能夠連接兩個(gè)零件部件，所以他們幾乎在全部設(shè)計(jì)中都被包括到。2.Springsaremechanicalmemberswhicharedesignedtogivearelativelylargeamountofelasticdeflectionundertheactionofanexternallyappliedload.彈簧是一個(gè)被設(shè)計(jì)為在外部負(fù)載作用下能發(fā)生相對大量彈性變形機(jī)械部件。61)adevelopinganddemandingindustry產(chǎn)業(yè)發(fā)展與要求2)propellershaft螺旋軸3)suspensioncomponents懸掛部件4)aslidingsplinedtypeofjoint滑動式花鍵5)towrearaxleshafts雙轉(zhuǎn)向軸軸6)tomeshwithalargerbevelgear與較大錐齒輪嚙合7)theuniversaljoints萬向節(jié)8)asteeringwheel轉(zhuǎn)向盤9)unevennessofroadsurface路面不平整度10)thetransverselineofthetheaxleshafts該軸橫向線11)tocauseexcessivetyrewear使輪胎磨損過分12)theexactlysimilardiameter完全相同直徑13)quarter-ellipticleafsprings四分之一橢圓鋼板彈簧片14)thetransmissionofshock震動傳輸15)roadsurfacevariation路面改變16)thefinal-drivegears最終傳動齒輪17)theprecisealignmentofshaft軸精準(zhǔn)定位18)arotatingdrum一個(gè)旋轉(zhuǎn)筒鼓19)ahandlever手柄20)belockedintheoneposition被鎖定在一個(gè)位置1)Thelubricationsystemprovidesaconstantflowoffilteredoiltoallmovingpartsoftheengine.Thesystemconsistsofanoilpantostoretheoil,apumptocirculateit,afiltertoremovesolidabrasiveparticles,andanoilgaugeorlightinthedriver’scompartmentforcheckingpurposes.譯:潤滑系統(tǒng)提供了源源不停過濾油給發(fā)動機(jī)各個(gè)運(yùn)動部件，該系統(tǒng)由一個(gè)油箱來儲存油，一個(gè)泵來輸送油，一個(gè)過濾裝置除去固體磨料顆粒，而且在駕駛室里有個(gè)油壓表或者指示燈來方便駕駛員檢驗(yàn)油量是否充分。2)Thedrivelineconsistsofmechanismsandunitswhichtransmittorquefromtheenginetothedrivewheelsandchangetorqueandrpminmagnitudeanddirection.譯:傳動系包含機(jī)制和單位，它將扭矩傳送到驅(qū)動輪并改變轉(zhuǎn)矩和轉(zhuǎn)速大小和方向。3)Ithasbeenseenthatiftheconditionsarenotveryabnormal,sufficientamountoftyresliptakingplaceunderrunningconditionswouldreleasethesestressescompletely.譯:能夠看到，假如運(yùn)行情況不是很正常，輪胎在行駛情況下發(fā)生足夠滑移，這些壓力就會被完全釋放出來。4)Mucheffortisrequiredtocranktheengineduringstarting,sinceitisnecessarytoovercomefrictioninthemovingenginecomponentsandtheresistanceofferedbythechargebeingcompressed.譯:發(fā)動機(jī)開始運(yùn)行需要經(jīng)過許多努力，比如必須要克服發(fā)動機(jī)運(yùn)動部件之間阻力和內(nèi)部裝置間壓力。5)Theclutchisafrictiondeviceusedtoconnectanddisconnectadrivingforcefromadrivenmember.Itisusedinconjunctionwithanengineflywheeltoprovidesmo0thengagementanddisengagementoftheengineandmanualtransmission.譯:離合器是一個(gè)將驅(qū)動力從驅(qū)動機(jī)構(gòu)連接或者斷開摩擦裝置，它由人力操控連接發(fā)動機(jī)飛輪來提供平滑連接與分離。6)Thedifferentialisagearsystemthattransferspowerfromthedriveshafttothedrivingaxles.Italsopermitsonedrivingwheeltoturnfasterthantheothertopreventskiddingandscuffingoftiresonturns.譯:差速器是一個(gè)將動力從主動軸傳送到驅(qū)動軸齒輪裝置，它存在能夠允許一個(gè)驅(qū)動輪速度比另一個(gè)更加快從而防止輪胎在轉(zhuǎn)動時(shí)發(fā)生打滑和擦傷。71.Greensand型砂2.Pourmoltenmetalintoapreparedcavity將熔融金屬倒入型腔中3.Morestableandrefractorysands耐熔砂4.Beusedtoproduceintricatemolds用來制作復(fù)雜鑄型5.Bothferrousandnonferrousmaterials黑色及有色金屬6.Partingpowder分形砂7.Berammed扎實(shí)8.Patterndraft拔模斜度9.Sprues,runnersandgates直澆道，橫澆道和內(nèi)澆口10.Apouringbasin外澆口11.Tomakeupforshrinkagelosses用于填補(bǔ)收縮損失12.Thecopeandthedrag上沙箱和下沙箱13.Someorganicbondingmaterials一些有機(jī)黏合材料14.Grossshrinkage縮孔15.Abottom-pouringladle底部澆注鐵水包16.Therateofsolidification凝固速率17.Toaffectthedegreeofliquidcontraction影響液體收縮程度18.Columnargrowthpresentatthemoldwall鑄型中針狀物成長19.Thefeedingcharacteristicsoftheriseringsystem冒口補(bǔ)縮特征20.Unwantedmetalprotrusions多出金屬突起1.Thefirststageintheproductionofsandcastingmustbethedesignandmanufactureofasuitablepattern.Castingpatternhastobemadelargerthanthefinishedcastingsizetoallowfortheshrinkagethattakesplaceduringsolidificationandcooling.在型砂鑄造生產(chǎn)中，第一階段是必須設(shè)計(jì)和制造適宜模型，考慮到鑄件在凝固和冷卻期間產(chǎn)生收縮，鑄件模型尺寸要比鑄件尺寸大。2.Ifahollowcastingistobemadethepatternwillincludeextensionpiecessothatspacestoacceptthesandcorearemoldedintothesand,Theseadditionalspacesinthemoldaretermedcoreprints.假如鑄造空心鑄件時(shí)，模型上包含伸長桿便于在砂中放置砂芯空間稱為型芯座3.Sandmoldsfortheproductionofsmallandmedium-sizedcastingsaremadeinamoldingbox.Themoldismadeintwoormorepartsinorderthatthepatternmayberemoved.中小型尺寸鑄件砂型是在一個(gè)砂箱中制造，砂型由兩部分或更多部分組成，以利于模型順利取出。4.Thisprocessoffillingandrammingmaybedonebyhandbutmoldproductionisautomatedinalargefoundrywiththemoldboxesmovingalongaconveyor,firstlytobefilledwithsandfromhoppersandthentopassundermechanicalhammersforramming.填充和扎實(shí)過程能夠手工完成，但在大型鑄造中砂型制造是自動完成，砂箱伴隨傳送帶移動，首先被料斗中砂子填滿，然后經(jīng)過機(jī)械錘被打?qū)崱?.Therisersshouldcoincidewiththehighestpointsofthemoldcavitysothatthedisplacedaircanreadilyescapefromthemold.Thesizesofrisersshouldbesuchthatthemetalinthemdoesnotfreezetoorapidly.冒口應(yīng)該與型腔最高點(diǎn)相連接，使得進(jìn)入空氣能夠輕易從模型中溢出，冒口尺寸應(yīng)該足夠大使模型中金屬不會太快凝固。6.Whenthemetalthathasbeenpouredintoasandmoldhasfullysolidified,themoldisbrokenandthecastingisremoved.Thecastingstillhastherunnerandrisersattachedtoitandtherewillbesandadheringtoportionsofthesurface.當(dāng)熔融金屬被傾倒到砂型內(nèi)并充分凝固以后，砂型將被打破取出鑄件，鑄件上依然帶有橫澆口和冒口而且依然有砂子粘在表面。81).bulkdeformationdfmetals金屬體積成形2).forging,rolling,orextruding鑄造、軋制、擠壓3).plasticdeformation塑性變形4).impactblows影響沖擊5).therecrystallizationpointofthemetal金屬再結(jié)晶點(diǎn)6).hotworkingandcoldworking熱加工和冷加工7).bettersurfacefinish愈加好表面光潔度8).hammerforging錘鑄造9).strikingthehotmetal熱金屬10).aslowsqueezingacting遲緩擠壓作用11).opendiesangcloseddies開模和封閉模具12).bevelgearswithstraightorhelicalteeth圓錐齒輪跟直齒輪或者螺旋齒輪齒13).impressiondies型腔模具14).eachofdiecavities每個(gè)模腔15).massproduction大規(guī)模生產(chǎn)16).ahomogeneouscircumferentialgrainflow均勻圓周顆粒流17).thethree-dimensionaldescription三維描述18).computersimulation計(jì)算機(jī)模擬19).hydraulicpresses液壓機(jī)20).berough-andfinished-machined是粗糙而且經(jīng)過機(jī)加工完成1.Forgingmeanstheshapingofmetalbyaseriesofhammerblows,orbyslowapplicationofpressure.Thesimplestexampleisablacksmith'sforgingofahotpieceofmetalbyhammeringthework-pieceonananvil.鑄造是指經(jīng)過一系列捶打或遲緩擠壓使金屬成形過程。最簡單例子就是鐵匠經(jīng)過在鐵砧上捶打一塊熱金屬來制造工件。2.Heavysmith'sforgingisfundamentallysimilar,differingonlyinthescaleoftheoperation,Thework-piecemaybeaningotof100tonsandthedeformingforceprovidedbyamassiveforginghammer,butthewholeprocessiscontrolledbythemastersmith,whodecideseachtimewhere,andwithwhatforce,theblowshouldtakeplace.鐵匠們沉重鑄造工作基本上是相同,不一樣地方只是在于鑄造規(guī)模,工件可能是一個(gè)100噸金屬錠，而且金屬錠變形所需要力是經(jīng)過一把大規(guī)模鑄造錘提供,不過整個(gè)過程都是由主鐵匠控制,決定每一次捶打在什么地方，用什么力量以及是否需要冷卻。3.Forgingoperationsmaybecarriedoutusingeitherforginghammersorforgingpresses.Withapress,asopposedtoahammer,pressureisslowlyappliedandplasticdeformationtendstooccurfairlyuniformlythroughoutthemeterial.鑄造時(shí)能夠用鑄造錘，也能夠用鑄造壓力機(jī)。與鑄造錘不一樣,經(jīng)過鑄造壓力機(jī)鑄造時(shí)，壓力被遲緩施加，塑性變形往往會相當(dāng)均勻地貫通整個(gè)材料。4.Forginghammersareoftwobasictypeswiththelargehammereitherdroppingontothework-pieceacceleratedbygravityaloneor,asinthesteamhammer,acceleratedbybothgravityandsteampressure.大型鑄造錘有兩種基本類型，一個(gè)捶打工件僅僅靠重力使大錘加速,另一個(gè)靠重力和蒸汽加速使大錘加速，如蒸汽錘。5.Smith'soropen-dieforgingisusedformakingverylargeforgingsorwhenthenumberofforgingsofaparticulardesignissmall.Open-dieforgingisalsousedtopreformmetalpriortofinalshapingbymeansofclosed-dieforging.錘鍛或開模鍛適適用于制造非常大鍛件，或少許特殊設(shè)計(jì)鍛件。開模鍛還能夠用于金屬閉模鍛之前粗加工。6.Closed-dieforginginvolvestheuseofaccuratelymachineddieblocks.Thecapitalcostofapairofdieblocksishigh,butthisisallowablewhenitisrequiredtomakeforgingstoclosedimensionaltolerancesandinlargequantity,aswouldbethecasefor,say,connectingrodsfirtheengineofapopularcar.閉模鍛包括到精準(zhǔn)加工模塊使用。一對模具塊成本很高,但當(dāng)鍛件尺寸公差要求很高，數(shù)量很大情況下，閉模鍛是適用91)carryinghigh-amperagecurrent帶有高電流2)theelectrodeandthework-piece電極和工件3)theweldpool熔池4)acolumnofionizedgascalledplasma等離子區(qū)柱狀電離氣體5)theoxidesandnitrides氮氧化物6）thepositiveions正離子7)deleterioussubstances有害物質(zhì)8）thenewlysolidifiedmetal新凝固金屬9)inoverheadwelding仰焊10）currentdensity電流密度11）depositionrate沉積速率12）anunbalancedmagneticfield不平衡磁場13）arcblow電弧偏吹14）theelectrodecoating焊條涂層15）inoverheadposition仰焊場所16）thecoolingrateofthedepositedmetal焊縫金屬冷卻速率17）amorehomogeneousmicrostructure更均勻顯微（結(jié)構(gòu)）18）asoomthflowofmoltenmetal熔融金屬平穩(wěn)流動19）cellulosic-coatedelectrodes纖維涂層焊條20）perpendiculartothecurrentpath垂直于電流通道1）Arcweldinginoneformoranotheristhemostwidelyusedformofwelding.Theelectricalsupplyislowvoltagebuthighamperageandmaybeeitheralternatingordirect.電弧焊在一個(gè)或另一個(gè)形式是應(yīng)用最廣泛焊接形式。電源供給低電壓，不過大電流,能夠是交流或直流。2)Theearliestformsofarcweldingusedcarbonelectrodes.Butnowadaysthearcisstruckbetweenametalelectrodeandthework-piece.Theelectrodemayeitherbeoftungstenorbeaconsumablemetalelectrodethatmelts,actingasasourceoffillermetal.最早形式電弧焊用碳電極。但如今弧金屬電極和工件之間。電極能夠是鎢或可熔化,作為填充金屬供源消耗性金屬電極。3)Analternating-currentarcisbrokenandre-establishedateachhalfcycleandthisleadstoarcinstabilityalthoughtheuseofarc-establishingagentsinthefluxcoatingofelectrodewirescanovercomethisproblem.交流電弧被打破,重新建立在每個(gè)半周期和這造成電弧不穩(wěn)定即使在電極布線焊劑涂層使用電弧建立劑能夠克服這個(gè)問題。4)Uncoatedweldingrodscanbeusedforarcwilding,butitismoreusualtouseflux-coatedelectrodes.Whensteelsareweldedusinguncoatedelectrodes,oxidesandnitridescanformandremainintheweldwithaconsequentlossoftoughness.裸焊接棒可用于電弧野生植物,但更通常使用焊劑涂層電極。鋼焊接使用裸電極時(shí),氧化物和氮化物能夠形成并保持在焊縫韌性。5)Flux-coatedelectrodesarewidelyused.Thecompositionofthecoatingiscomplexandavarietyofdifferentcoatingsareusedtocaterfordifferenttypesofweldingapplication.焊劑涂層電極被廣泛使用。涂料組成很復(fù)雜,各種不一樣涂料用于滿足不一樣類型焊接應(yīng)用。6)Inthiscasetheelectronflowisfromelectrodetowork-piece.Aconcentratedarcissuesfromtheelectrodetipandheatingofthework-pieceislargelyconfinedtotheverysmallareabeneaththeelectrode.在這種情況下,電子流動從電極到工件。集中弧電極頭和工件加熱問題主要局限在極小區(qū)域下電極。101)plaincarbonsteel普通碳素鋼2)carboncontent含碳量3)lowcarbonsteel低碳鋼4)mediumcarbonsteel中碳鋼5)highcarbonsteel高碳鋼6)becoldworked冷加工7)beheattreated熱處理8)contain20pointofcarbon碳含量0.2%9)inthehot-rolledcondition熱軋狀態(tài)10)heat-treat-hardenedplaincarbonsteel熱處理淬硬普通碳素鋼11)free-machiningsteels易切削鋼12)hotshort熱脆13)coldshortness冷脆性、低溫脆性14)theisothermaltransformationcurves等溫轉(zhuǎn)變曲線15)grainrefinement晶粒細(xì)化16)stainlesssteel不銹鋼17)AISIsteelsAISI鋼18)iron-carbonequilibriumdiagram鐵碳合金平衡相圖19)toolanddiesteels工具鋼和模具鋼20)highcorrosionandchemicalresistance耐高腐蝕能力和抗化學(xué)作用1)Insimpleterms,aplaincarbonsteelmaybesaidtobeanalloyofironandcarboncontaininglessthan1.7%carbon.Inpractice,however,thesesteelsrarelycontainmorethan1.4%carbonandotherelementsarealsopresent,eitherasdeliberateadditions(e.g.manganese)orasimpurities(e.g.sulphurandphosphorus).簡單來說，普通碳素鋼被認(rèn)為是一個(gè)含碳量少于1.7%鐵碳合金。然而，實(shí)際上，這些鋼含碳量極少超出1.4%，同時(shí)還含有一些其余元素，比如一些額外添加物（如錳）或雜質(zhì)（如硫和磷）2)Inthemanufactureofmaterial,completedeoxiadationisnotcarriedoutanditismadeasrimmingsteel.Itisproducedashotandcoldworkedsheet,strip,rod,wire,andtube,andisavailableinthehot-workedorprocessannealedcondition.在材料加工過程中，不完全脫氧還原被加工成沸騰鋼。它經(jīng)過熱加工或冷加工被制成板材、帶材、棒材、線材和管材，這些也可在熱加工和退火條件下取得。3)Thestrengthandhardnessofthesesteelislow,butahardsurfacecanbeobtainedbycarburizinginordertocombineawear-resistantsurfacewithtoughcoreproperties.這類鋼強(qiáng)度和硬度很低，但能經(jīng)過滲碳作用表面硬化，他兼顧了表面耐磨和內(nèi)部韌性很好特點(diǎn)。4)Asthecarboncontentisraisedabove0.2%,thestrengthincreasesintotherangerequiredforconstructionalpurpose,buttheductilitydecreases.Thefabricationqualities(workingandweldingcharacteristics)ofthismaterialareverygood.當(dāng)含碳量上升超出0.2%時(shí)，需求范圍內(nèi)結(jié)構(gòu)用途強(qiáng)度增加，不過延展性會下降。材料制造質(zhì)量（承載性和焊接特征）會非常好。5)Mediumcarbonsteelsareoftenquenched-hardenedandfullytemperedtogivegoodstrengthwithmaximumtoughness,whicharethepropertiesrequiredofcomponentssuchasshafts,gearsandconnectingrods.中碳鋼常被淬火和完全回火處理以賦予高強(qiáng)度同時(shí)擁有最大韌性，這些特征都是像軸、齒輪和連桿這一類零件所需要。6)Highcarbonsteelsarequenchhardenedandlightlytemperedtogivehighhardnesswithonlylimitedtoughness.Materialinthisclassificationismainlyusedformakingfairlysmall,reactivelyinexpensivecuttingtoolssothatthegroupasawholeisknownascarbontoolsteel.高碳鋼經(jīng)過淬火和低溫回火來給予高硬度同時(shí)兼有一定韌性。這類材料主要被用于加工相當(dāng)小而可靠，而且廉價(jià)切削工具，所以通常被稱為碳素工具鋼。111.allotoropicmaterials同素異晶體2.plainlowcarbonsteels普通低碳鋼3.hypoeutectoidsteel亞共析鋼4.normalizedsteel正火鋼5.hypereutectoidsteel過共析鋼6.eutectoidcomposition共析成份7.grainboundaries晶界8.ferritematrix鐵素體基體9.about60℃abovetheAc1temperatureAc1溫度以上大約60℃10.thenoseoftheI-Tcurve等溫曲線鼻部11.coolingrate冷卻溫度12.quenchingmedia淬火介質(zhì)13.thermalstress熱應(yīng)力14.thermalshock熱沖擊15.atemperedsteel回火鋼16.temperbrittlement回火脆性17.inthetemperingordrawingprocedure回火時(shí)18.hardenedsteel淬硬鋼19.fullannealing完全退火20.todissolveallthecementite溶解全部滲碳體1.Theprincipalkindsofheat-treatmentusedinpractice,whichdifferentlyaffectthestructureandproperities,andwhichareassignedtomeettherequirementsmadetothesemifabricatedmaterials(casting,forging,rolledstock,etc.）andfinishedarticles,are:(1)annealing;(2)normalizing;(3)hardeningand(4)tempering.在實(shí)踐中用到能對結(jié)構(gòu)和性質(zhì)有不一樣影響，并被分配滿足半成品材料（鑄造，鑄造，軋制成品等）要求熱處理基本類型是：（1）退火；（2）正火；（3）硬化和（4）退火。2.Normalizingraisesthestrengthandhardnessofmedium-andhigh-carbonsteelsby10to15percentascomparedtoannealedsteel.與退火相比，正火提升了中碳鋼和高碳鋼10%—15%強(qiáng)度和硬度。3.Martensiteisveryhardandbrittle,havingamuchhighertensilestrengththanthesteelwithapearlitemicrostruture.馬氏體非常硬和脆，具備比珠光體組織鋼更高抗拉強(qiáng)度。4.Tempering,ordrawing,isaprocessofreheatingasteelpartthathasbeenpreviouslyhardenedtotransformhardmartensiteintosofterstructure.Thehigherthetemperingtemperatureused,thesofterandtoughthepiecebecomes.回火，是一個(gè)加熱鋼部分已被改造成軟硬質(zhì)馬氏體結(jié)構(gòu)以前硬化過程?；鼗饻囟仍礁撸摼蜁饺彳浐蛨?jiān)韌5.Forlowcarbonsteels,normalizingenablesabettersurfacefinishtobeobtainedinmachinhingandraisestheproductioncapacity.對于低碳鋼而言，正火在機(jī)械加工中能夠取得愈加好表面光潔度和提升生產(chǎn)能力。6.Incommercialtemperingthetemperaturerangeof250-425℃isusuallyavoidedbecauseofanunexplaindembrittlement,orlossofductility,thatoftenoccurswithsteelstemperedinthisrange.在工業(yè)上，通常要防止在250℃到425℃范圍內(nèi)回火，因?yàn)檫@個(gè)范圍內(nèi)回火鋼經(jīng)常會產(chǎn)生無法解釋脆性或塑性喪失現(xiàn)象。121.thenominalsizeornominaldimension公稱尺寸或公稱通徑2.actualsizeandlimitsofsize實(shí)際尺寸和極限尺寸3.upperdeviationandlowerdeviation上偏差和下偏差4.clearancefitandinterferencefit間隙配合和過盈配合5.theactualdimensionsofthefinishedproducts成品實(shí)際尺寸6thematingparts配合零件7.thehole-basissystem基孔制8.generalinterchangeability通常交換性9.thepositionofthezoneoftolerance公差帶基本尺寸10.representthevalueofthiszoneoftolerance代表公差帶值11.thenominalsizeornominaldimension公稱尺寸或公稱通徑12.actualsizeandlimitsofsize實(shí)際尺寸和極限尺寸13.upperdeviationandlowerdeviation上偏差和下偏差14.clearancefitandinterferencefit間隙配合和過盈配合15.theactualdimensionsofthefinishedproducts成品實(shí)際尺寸16.thematingparts配合零件17.thehole-basissystem基孔制18.generalinterchangeability通常交換性19.thepositionofthezoneoftolerance公差帶基本尺寸20.representthevalueofthiszoneoftolerance代表公差帶值1.Sinceitisimpossibletomachineaparttoanexactsize,adesignermustspecifyanacceptablerangeofsizesthatwillpermittheparttofitandfunctionasintended.因?yàn)樗皇菣C(jī)械零件一部分確實(shí)切尺寸，設(shè)計(jì)者必須指定尺寸可接收范圍，將允許部分誤差以實(shí)現(xiàn)配合和功效與預(yù)期相同2.Themaximumandminimumsizesinpartdimensionsthatareacceptablearelimitsbetweenwhichtheactualpartdimensionmustfall.實(shí)際尺寸必須落在可接收最大和最小尺寸程度之間3.Toleranceondrawingisoftenindicatedbyspecifyingalimit,orbyplusandminusnotations.Withplusandminustolerancing,whenthetoleranceisbothaboveandbelowthenominal(truetheoretical)size,itissaidtobebilateral(twosides).繪圖上公差是經(jīng)常經(jīng)過被指定一個(gè)限制,正或者是和負(fù)符號。伴隨正負(fù)公差值,公差值處于公稱尺寸之上和之下時(shí),被稱為雙邊4.Althoughamachinistisnotusuallyconcernedwithestablishingtoleranceandlimitspecifications,youcaneasilyseehowfitproblemscanbecreatedbyoverlappingtolerancesdiscussedinthisexample.盡管工程師通常不關(guān)注公差建立和規(guī)格限制，但你能很輕易從這個(gè)示例中看出,怎樣配合問題能夠經(jīng)過重合討論公差創(chuàng)建.5.Manytimesamachinistisconcernedwithpressorinterferencefits.Inthiscasetwopartsareforcedtogetherusuallybymechanicalorhydraulicpressing.很多時(shí)候，機(jī)械加工包括壓力或過盈配合.在這種情況下，兩部分通常是經(jīng)過機(jī)械或液壓壓制在一起。6.Althoughstandardizedmeasurementisessentialtomodernindustry,perhapsevenmoreimportantarethedesignspecificationsthatindicatethedimensionofapart.即使標(biāo)準(zhǔn)化測量是當(dāng)代工業(yè)關(guān)鍵,可能更為主要是表明部分尺寸設(shè)計(jì)規(guī)格。LESSON131.hydraulicpowertransmissionsystem液壓動力傳動系統(tǒng)2.Theamountoffluid-flowtotheactuators抵達(dá)執(zhí)行部件液體流量3.Fromhydraulicpowertomechanicalpower將液壓能轉(zhuǎn)換為機(jī)械能4.Fluidstorageandconditioningequipment油液貯存和調(diào)整裝置5.Thetechnologyofhydraulics液壓技術(shù)6.Thegeometryofthemachine機(jī)構(gòu)幾何學(xué)7.Pneumaticsystems氣壓系統(tǒng)8.Oilunderpressure壓力油9.Directionalcontrolvalve方向控制閥10.Constantforceortorque恒定力或力矩11.Safety,compactnessandreliability安全性，緊湊性和