第1題HCPstructuralmetalhas()AMgBWCNiDα-Fe第2題HCPstructuralmetalhas()ACdBWCNiDα-Fe第3題Thesolidsolutionischaracterizedbymaintainingthecrystalstructuretypeof().ASoluteBCrystalCUnitcellDSolvent第4題Inthenon-cubicsystem,thecrystalorientationandcrystalplanewithexactlythesameindex()AMaybeparalleltoeachotherBIntersectat45°CUncertainincludedangleDMaybeperpendiculartoeachother第5題ThesizesrBandrAofthebody-centeredcubicoctahedrongapandtetrahedralgapare()respectively.A0.29,0.15B0.414,0.29C0.414,0.15D0.15,0.29第6題Theclose-packedsurfaceanddirectionofbody-centeredcubicare().A{100},<111>B{110},<111>C{111},<110>D{111},<111>第7題Theoctahedralvoidofwhichstructureissmallerthanthetetrahedralvoidinametalcrystalstructure().AFace-centeredcubicstructureBHexagonalclose-packedstructureCBody-centeredcubicstructure第8題Thesymbolmeans().ACrystalfacegroupBCrystalorientationgroupCCrystalorientation第9題InanaluminumcrystalhavingaFCCstructure,theatomiccoordinationnumberperaluminumatomonthe(111)planeofthepresentlayeris().A6B8C4第10題Thedensityofsimplecubiccrystalsis().A65%B52%C58%第11題Thecubicsystemincludes()ASimplecubeBFace-centeredcubicCBase-centeredcubicDBody-centeredcubic正確答案：ABD第12題Ironhaspolymorphismandwillformcrystalstructuressuchas()atdifferenttemperatures.AFace-centeredcubicBBody-centeredcubicCSimplecubicDBase-centeredcubeEHexagonalclose-packed正確答案：AB第13題Thepointsincrystalstructuresandspatiallatticesrepresentatoms.()第14題Similarcrystalstructurescanbelongtodifferentlattices.()第15題Variousbasicunitcellscanbeselectedfromthelatticedependingondifferentcriteria.()第16題Thedistinctionbetweencomplexandsimpleunitcellsisthatnodalpointsarepresentatthebody-center,face-center,orbase-center,inadditiontothevertices.()第17題Theatomsinthecrystalstructurearearrangedinaperiodicmanner,indicatingshort-rangeorder.()第18題Whentheindicesinthecrystalorientationandtheplaneindices(hkl)areidentical,thecorrespondingcrystalorientationsandplanesareperpendiculartoeachother.()第19題Ifthecrystalorientationpointsoppositely,theindices'numbersremainthesamebutthesignsarereversed.()第20題Theintersticesinabccstructurearenotregularpolyhedra;thetetrahedralintersticeisincludedwithintheoctahedralinterstice.()第21題Theformationofasubstitutionalsolidsolutionintoaninfinitesolidsolutionrequiresthatthesoluteandsolventhavethesamecrystalstructure.()第22題59.()第23題Theatomsinacrystalarearrangedinaregular,periodicmannerinspace,whereasinanamorphoussolid,theatomsarearrangedrandomly.()第24題Whenselectingtheunitcell,thechosencubeshouldpossessthesamesymmetryasthemacroscopiccrystal.()第25題Thespatiallatticeisageometricalabstractionofthearrangementofparticlesinacrystal,withonly14types,whiletheactualexistingcrystalstructuresareinfinite.()第26題Elementsformingsubstitutionalsolidsolutionscanbecompletelymiscible,whilethoseforminginterstitialsolidsolutionscanonlybepartiallymiscible.()第27題Onlytheelementsofsubstitutionalsolidsolutionscanachievecompletemiscibility,whileinterstitialsolidsolutionsareonlypartiallymiscible.()第28題Thesolubilityofinterstitialsolidsolutionsdependsnotonlyonthesizeofthesoluteatomsbutalsoontheshapeandsizeoftheinterstitialsitesinthecrystalstructure.()第29題Metalshavethreetypicalspatiallattices:body-centeredcubic,face-centeredcubic,andhexagonalclose-packed.()第30題Completemiscibilityispossibleonlybetweenthetwocomponentsofasubstitutionalsolidsolution,butnotinaninterstitialone.()第1題Theexistenceofpointdefectsinthecrystalmakestheresistance().AIncreaseBDecreaseCNochange第2題Sliplinescanbeobservedunder().AOpticalmicroscopeBElectronmicroscopeCNakedeye第3題Thedirectionandmagnitudeofcrystalslipcanberepresentedby().ABurgersvectorBDislocationlineCSlipdirection第4題TheBurgersvectorofascrewdislocationis().AParalleltothedislocationlineBPerpendiculartothedislocationlineCUnrelatedtothedislocationdirectionDNeitherparallelnorperpendiculartothedislocationline第5題Inactualcrystals,linedefectsappearas().AVacanciesandinterstitialatomsBDislocationsCGrainboundaries第6題Soluteatomsorimpurityatomstypicallyexistinmetals,andtheirpresence().AAlwaysincreasesthelatticeconstantBAlwaysdecreasesthelatticeconstantCMayincreaseordecreasethelatticeconstant第7題Adislocationis()AThermodynamicequilibriumdefectBLineardefectCOne-dimensionaldefectDVerysmallintwodirections正確答案：BCD第8題Theslipofanedgedislocationis()APositiveandnegativeedgedislocationmovementinoppositedirectionsBSequentialrow-by-rowmotionCThecrystalplanedeterminedbyBurgersvectoranddislocationlinemustbeitsslipplaneDOveralltranslationonatomicsurface正確答案：ABC第9題TheSlipofscrewdislocationis()ATheleftscrewandtherightscrewmoveinoppositedirectionsofdislocationBMoveonanyatomicsurfacepassingthroughthedislocationlineCOveralltranslationontheatomicsurfaceDSequentialrow-by-rowmotion正確答案：AD第10題Frankeldefectsarevacancies-interstitialpairsformedbythemigrationofatomsintointerstitialsites.()第11題Dislocationlinescanonlyterminateatcrystalsurfacesorinterfaces,notwithinthecrystalinterior.()第12題Duringslip,themotiondirectionofanedgedislocationisalwaysparalleltothedislocationlineandperpendiculartotheBurgersvector.()第13題Thecrystalsurfaceisgenerallytheonewiththehighestatomicdensity,anditssurfaceenergyisrelatedtocurvature:thelargerthecurvature,thegreaterthesurfaceenergy.()第14題Screwdislocationshaveextrahalfplanes.()第15題TheBurgersvectorcanbedeterminedusingaBurgerscircuit.()第16題Theslipplaneofanedgedislocationisunique.()第17題Theslipplaneforscrewdislocationsisnotunique,andtheycansliponallplanesparalleltothedislocationline.()第18題Dislocationlinesforedgedislocationsmaybestraight,polygonal,orcurved,buttheymustbeparalleltotheslipdirectionandslipvector.()第19題Screwdislocationsareclassifiedintoleft-handedandright-handedtypes.()第20題Thedislocationlinesforscrewdislocationsareparalleltotheslipvectorandmustbestraight.()第21題TheBurgersvectorofadislocationlineisnotunique.()第22題Adislocationcanbedefinedasacrystaldefectwithanon-zeroBurgersvector,whichmayterminatewithinthecrystal.()第23題Screwdislocationscanundergobothclimbandslip.()第24題Edgedislocationscanonlyundergoclimb.()第25題Aperfectcrystalcontainsnovacancies.()第26題Atroomtemperature,vacanciescanbecompletelyeliminated.()第27題Thescaleofpointdefectsissosmallthattheymainlyaffectthephysicalpropertiesofcrystals,withnegligibleimpactonmechanicalproperties.()第28題Asthedislocationlinescurve,theBurgersvectorbecomesvariable.()第29題Climbdoesnotdirectlyaffectplasticdeformation,butitcanfacilitatecontinuedslip.()第30題Afteradislocationinteraction,abendinevitablyformsonthedislocationline.()ChapterIIItest第1題Insubstitutionalsolidsolutions,atomicdiffusiontypicallyoccursby().AAtomicexchangemechanismBInterstitialmechanismCVacancymechanism第2題IntheexpressionofFick'sfirstlaw,aminussignindicates()ADiffusionoccursfromhighconcentrationtolowconcentration.BDiffusionoccursfromlowconcentrationtohighconcentration.CThedirectionofdiffusionisindependentofconcentration.DItissimplyasymbolandhasnoinherentmeaning.第3題Theexperimentallymeasureddiffusioncoefficientsofcarbonintitaniumatvarioustemperaturesare2X10-9cm2/s(736°C),5X10-9cm2/s(782°C)and1.3X10-8cm2/s(838°C).(1)Determineiftheexperimentalresultsconformto().(2)Calculatetheactivationenergyfordiffusionas().AConformsBDoesnotconformCConformityisnotaconcernD2342787J/molE2032787J/molF2589879J/mol正確答案：AD第4題Fick'sfirstlawdescribesthecharacteristicsofsteady-statediffusion,meaningthattheconcentrationdoesnotchangewith()distance.ADistanceBTimeCTemperatureDFlowrate第5題Thegrainboundarydiffusionrateis()comparedtotheintragranulardiffusionrate.AHigherBLowerCEqualDIncomparable第6題Solidmetaldiffusionismostlikelytooccuraccordingtothe()mechanism.AInterstitialdiffusionmechanismBTranspositiondiffusionmechanismCVacancydiffusionmechanism第7題Factorsaffectingdiffusioninclude().ATemperatureBSolidsolutiontypeCCrystalstructureDCrystaldefectsEChemicalcompositionFEffectofstress正確答案：ABCDEF第8題Diffusionmechanismsinclude().AVacancymechanismBInterstitialmechanismCExchangemechanismDGrainboundarydiffusionESurfacediffusion正確答案：ABCDE第9題Fick'sfirstlawindicatesthatthediffusionfluxthroughagivencross-sectionisproportionaltotheconcentrationgradientperpendiculartothiscross-section,anditsdirectionalignswiththeconcentrationdecreasedirection.()第10題()第11題Ifthereisnodiffusionfluxinthesolid,itindicatesthatatomshavenotdiffused.()第12題Sincethedirectionofeachjumpofthesolidsolutionatomsisrandom,thediffusionfluxinthiscaseiszero.()第13題Atomsonthegrainboundaryaredisordered,withnovacanciespresent;hence,atomsdiffusingviathevacancymechanismcannotdiffuseatthegrainboundary.()第14題Theactivationenergyforinterstitialdiffusionislowerthanthatforsubstitutionaldiffusion.()第15題Thediffusioncoefficientsofelementslikenitrogenandcarboninα-Fearehigherthaninγ-Fe.Thisisbecausethebody-centeredcubicstructurehasalowerdensitythantheface-centeredcubicstructure,allowingeasieratomicmigration.()第16題ThediffusioncoefficientDisdeterminedsolelybythecrystalstructure.()第17題Heliumhasahighsolubilityinaustenite,indicatingthatitsdiffusioncoefficientinausteniteisfasterthaninferrite.()第18題Thefirstlawofdiffusionisapplicableonlytosteady-statediffusion.()第19題Diffusionalwaysproceedsfromregionsofhighconcentrationtoregionsoflowconcentration.()第20題Thediffusioncoefficientofinterstitialsoluteatomsislowerthanthatofsubstitutionalsoluteatoms.()第21題Diffusionwilloccuraslongasthereisaconcentrationgradientinthealloy.()第22題ThemagnitudeofthediffusionfluxJreferstotheamountofflowthroughanycross-sectionperunittime.()第23題TheKirkendalleffectsupportsthevacancymechanism.()第24題Defectscausedistortionsthatfacilitateatomicmigrationmoreeasilythaninperfectcrystals,leadingtohigherdiffusionrateswithindefectscomparedtowithinperfectcrystals.()ChapterIVtest第1題Insupercooledliquids,thecriticalsizeofthecrystalembryo()cannotgrowspontaneously.AGreaterthanBLessthanCEqualtoDNotconsidered第2題Thestructureofliquidmetalis().AShort-rangeordered,long-rangeorderedBShort-rangedisordered,long-rangeorderedCShort-rangeordered,long-rangedisorderedDShort-rangedisorder,long-rangedisorder第3題Theatomicgroupinthe"short-rangeregulararrangement"thatintermittentlyforms,dissolves,andconstantlytransitionsinliquidmetalisreferredtoas().AStructuralfluctuationBCompositionalfluctuationCEnergyfluctuationDSupercoolingcapacity第4題Theembryoradiuscorrespondingto△G*iscalled(),referringtoembryosthatcanachieveacertainsize,growsteadilywithoutdiminishing.ACriticalnucleusradiusBMaximumnucleusradiusCMinimumnucleusradiusDVisiblenucleusradius第5題Crystallizationiscompletedthroughnucleationand().AGrowthBCoolingCOverheatingDSupercooling第6題Thefundamentaltechniqueforrefiningingotgrainsis()AControlthedegreeofsupercoolingBModificationCVibrationandstirring正確答案：ABC第7題Whenliquidmetalcrystallizesandsolidifies,itrequiresnucleation,whichincludes()AHomogeneousnucleationBHeterogeneousnucleationCParticlenucleationDInterfacenucleation正確答案：AB第8題Undercoolingreferstothedifferencebetweenthemeltingpointandthetemperaturewhereaplateauappearsonthecoolingcurveduringcrystallization;whereasdynamicundercoolingreferstothedifferencebetweentheactualliquidphasetemperatureandthemeltingpointduringcrystallization.()第9題Duringmetalcrystallization,atomsrearrangefromadisorderedliquidphasetoanorderlysolidphase,reducingtheentropyofthesystem,whichisaspontaneousprocess.()第10題Thelargeststructuralfluctuationsfoundinliquidmetalsatanytemperaturearereferredtoasembryos.()第11題Thecriticalnucleusreferstothesizeoftheembryoatwhichthereductioninfreeenergyfullycompensatesfortheincreaseinsurfacefreeenergy.()第12題Inliquidmetals,anyembryothatemergeswitharadiussmallerthanthecriticalnucleuscannotnucleate;however,nucleationispossibleifsufficientenergyfluctuationprovidesthenecessarynucleationwork.()第13題Heterogeneousnucleationisalwayseasierthanhomogeneousnucleationbecausetheformerusesexternalparticlesasthecrystallizationcore,unlikethelatterwhichformsaninterface,leadingtoanincreaseinfreeenergy.()第14題Nomatterthetemperaturedistribution,commonlyusedpuremetalsgrowwithadendriticinterface.()第15題Puremetalswithasmallamountofimpuritiesarethermodynamicallystable.()第16題Thesizeofthecriticalnucleusradiusisonlyrelatedtothedegreeofundercooling.()第17題Duringthesolidificationofliquidmetal,therequiredundercoolingforheterogeneousnucleationislessthanthatneededforhomogeneousnucleation.Thisisbecause,duringheterogeneousnucleation,solidphaseparticlescangrowascrystalnuclei,resultinginlowercriticalnucleationwork.()第18題Underfactoryproductionconditions,asthedegreeofundercoolingincreases,thecriticalnucleusradiusdecreases,andthecrystallizationcoolingrateincreases.Thegreaterthenucleationratetogrowthrateratio,thefinerthegrains.()第19題Anycoolingandcrystallizationprocessofliquidmetalscanbedividedintotwostages.Firstly,nucleationoccurs.Oncenucleationceases,growthbegins,allowingthecrystalgrainstofilltheentirevolume.()第20題Modificationtreatmentistheprocessofalteringthecompositionandqualityofmaterialsduringpouring.()第21題Solidificationandcrystallizationarebothprocesseswhereasubstancetransitionsfromaliquidstatetoasolidstate;therefore,solidificationisessentiallythecrystallizationprocess.()第22題Thefasterthecoolingrate,thelowerthetheoreticalcrystallizationtemperature.()第23題Recentresearchindicatesthatthestructureofliquidmetalsisquitesimilartothatofsolidmetals,whilebeingsignificantlydifferentfromgaseousforms.()第24題Thetransitionofmetalsfromliquidtosolidinvolveschangingfromashort-rangeorderedstructuretoalong-rangeorderedstructure.()第25題Thefasterthecoolingrateduringmetalcrystallization,thefinertheresultingcrystalgrains.()第26題Whenotherconditionsarethesame,thegrainsofcastingsmadewithmetalmoldsarefinerthanthosemadewithsandmolds.()第27題Whenotherconditionsarethesame,thegrainsofcastingspouredathightemperaturesarefinerthanthosepouredatlowtemperatures.()第28題Whenotherconditionsarethesame,thegrainsinthin-castpartsarefinerthanthoseinthick-castparts.()第29題Puremetalgrowthexhibitsadendriticinterfaceaslongasthetemperaturegradientisnegative.()第30題Theterm'criticalnucleus'referstoembryosizewhenthereductioninsystemfreeenergycompensatesfora2/3increaseinsurfacefreeenergy.()ChapterVtest第1題Ifthereisnocompositionalundercoolingduringthesolidificationofcastings,thecastingstructurewillbe().AEntirelyequiaxedcrystalsBEntirelycolumnarcrystalsCColumnarcrystals+centralequiaxedcrystals第2題Theeutecticpointislocatedat().Aα-phasepointintheeutecticstructureBβ-phasepointintheeutecticstructureCEutecticpoint第3題Thetransformationwhereasolidphaseofacertaincompositionandaliquidphaseofacertaincompositiongenerateanothersolidphaseofacertaincompositionataconstanttemperatureiscalled().AEutectictransformationBPeritectictransformationCEutectoidtransformationDPeritectoidtransformation第4題Thetransformationwherealiquidphaseofacertaincompositiongeneratestwosolidphasesofacertaincompositionataconstanttemperatureiscalled().AEutectictransformationBPeritectictransformationCEutectoidtransformationDPeritectoidtransformation第5題Byexaminingthemicrostructureofeutectoidsteel,itisobservedthattheconcentrationofcementitelamellaevariesamongdifferentareasintheimage.Wherethelamellaearedense,thecarboncontentishigher,whereasinsparserareas,itislower.()第6題Theoccurrenceofshrinkagecavitiesandporosityisduetotheinabilitytosupplyfeedduringsolid-stateshrinkage.()第7題Therelativequantityofeutecticphasescanbecalculatedusingtheleverrulealongtheeutecticline.Sincetheeutecticlineispartofthethree-phaseregion,theleverruleappliesnotonlytotwo-phaseregionsbutalsotothree-phaseregions.()第8題Metalscanbeeffectivelypurifiedthroughrepeated"melting-solidification"cyclesofsolidsolutionalloyrodsandbyemployingdirectionalrapidsolidificationtechniques.()第9題Thefundamentaldistinctionbetweenferriteandausteniteistheirsolidsolubility;theformerislow,whilethelatterishigh.()第10題InFe-Fe3Calloys,secondarycementiteexistsonlyintheequilibriumcrystallizationstructureofhypereutectoidsteel.()第11題Forallcompositionsofcarbonsteel,asthecarboncontentincreases,therelativeamountofferriteinthemicrostructuredecreases,whiletherelativeamountofpearliteincreases.()第12題InthemicrostructureofeutecticwhitecastironwithWc=4.3%,thewhitematrixisFe3C,includingFe3CI,Fe3CII,Fe3CIII,Fe3Ceutectoid,andFe3Ceutectic.()第13題Eutecticalloysarepuresubstances.()第14題Themicrostructureofpseudo-eutecticalloysissimilartothatofeutecticalloysbutwithdifferentcompositions.()第15題Divorcedeutecticscanonlybeformedunderconditionsofnon-equilibriumcrystallization.()第16題Aphaseisdefinedasahomogeneousbodywithidenticalstructure,properties,andstateofaggregation.()第17題Forphasechangereactionstotakeplace,thermodynamicandkineticconditionsmustbemet.()第18題Thecrystallizationprocessofbinaryalloysoccursataconstanttemperature.()第19題Innon-equilibriumsolidification,thefasterthecoolingrate,themoreseveretheresultingmacrosegregation.()第20題Duringhomogeneoustransformation,thecompositionoftheliquidandsolidphaseschangesinversely.()第21題Thehomogeneoustransformationinvolvesthedirectcrystallizationofacompoundfromtheliquidphase.()第22題Theleverrulecanbeusedtocalculatetherelativeamountsofeachphasewithinathree-phaseregion.()第23題Factorsaffectingcompositionalundercoolingincludethealloy'scharacteristicsandexternalconditions.()第24題Thealloyneartheeutecticpointisrapidlycooled,resultinginapartialeutecticstructure,knownasapseudo-eutectic.()第25題Aftertheperitectictransformation,thereiseitheraremainingliquidphaseorasolidphase.()第26題Pearliteisaresultoftheeutectoidtransformation.()第27題Ascarboncontentincreases,theamountofferritewithiniron-carbonalloysgraduallyrises.()第28題Alliron-carbonalloysarecomposedoftwophases:ferriteandcementite.()第29題Duetotheoccurrenceofdesolvationtransformation,thestructureofhypoeutecticwhitecastironatroomtemperaturedoesnotcontainpearlite.()第30題Peritecticsegregationcanbeeliminatedthroughdiffusionannealing.()ChapterVItest第1題Basedontheverticalsectionoftheternaryphasediagram,onecan().AAnalyzethesolidificationprocessofthealloyBCalculatetherelativeamountsofeachphaseusingtheleverruleCIdentifytheexactcompositionofthealloyDExaminethetrendsinphasecompositionchanges;第2題ThephasetransformationsofaspecimencomposedofthreeconstituentswithvaryingtemperatureareexaminedusingX-raydiffraction()inair,anduptothecoexistenceof()canbedocumented.AFourphasesBTwophasesCFivephasesDThreephases正確答案：DA第3題Intheisothermalsectionofaternaryalloyphasediagram,thetriangularregionisthe()equilibriumarea.ASingle-phaseBFour-phaseCTwo-phaseDThree-phase.第4題Inaternaryalloyphasediagram,theisothermalsectionofthethree-phaseregionformsa()triangle.ACanbestraight-edgedorcurved-edgedBNottriangularCCurvededgeDStraightedge第5題Intheisothermalsectionofaternaryalloyphasediagram,thethree-phaseregionisastraight-edgedtriangle,withitsthreeverticesconnected().AFour-phaseregionBTwo-phaseregionCSingle-phaseregionDThree-phaseregion第6題Inaternaryalloyphasediagram,theisothermalsectionofthethree-phaseregionformsatriangle,witheachsidetouching().AThree-phasezoneBFour-phasezoneCTwo-phasezoneDSingle-phasezone第7題Inaternaryphasediagram,the()phaseequilibriumtransitionoccursmostoften.A4B5C2D3第8題Inaternaryphasediagram,thefour-phaseequilibriumareaisdepictedas()AAplaneBApointCAhorizontallineDAthree-dimensionalspace第9題Inaternaryphasediagram,thepurposeoftheleverlawis()ACalculatetherelativepercentageofeachphaseduringtwo-phaseequilibriumonthehorizontalsectionBCalculatetherelativepercentageofeachphaseduringthree-phaseequilibriumonthehorizontalsectionCCalculatetherelativepercentageofeachphaseduringthree-phaseequilibriumontheverticalsectionDCalculatetherelativepercentageofeachphaseduringtwo-phaseequilibriumontheverticalsection;第10題ThecompositionofA90B5C5alloyismoreclearlyexpressedby()inthecompositiondiagram.ARighttriangleBIsoscelestriangleCEquilateraltriangleDNoneoftheabove第11題IntheternaryphasediagramA-B-C,thecompositionatpointOis().A50%A,20%B30%CB30%A,20%B50%CC50%A,30%B20%CD20%A,50%B30%C第12題InaternaryphasediagramformedbyA-B-Ccomponents,anypointonalineparalleltosideABwithintheequilateraltriangle△ABCrepresentsitscompositionas().A.TheconcentrationratioofAtoBisconstantCisconstantB.TheconcentrationofDisconstantC.TheconcentrationofcomponentEisconstantD.Theconcentrationof正確答案：E第13題Theequationfortheternaryperitecticreactionis().AL+α→β+γBL+α+β→γCL+α→β+γDL→α+β+γ第14題Inaternaryphasediagram,theequilateraltriangleiscommonlyusedastheconstituenttriangle().AEquilateraltriangleBRighttriangleCIsoscelestriangle第15題Fromtheverticalcross-sectionoftheternaryphasediagram,()canbededuced.AAnalyzethevariationofphasecompositionBAnalyzethealloy'ssolidificationprocessCUsetheleverruletocalculatetherelativeamountofeachphase第16題Therelativeamountofphasesinaternaryphasediagramcanbedeterminedby().AStraightlineruleBLeverruleCCenterofgravityruleDTangentrule正確答案：AB第17題Theisothermalsectionoftheternaryphasediagramcanbeemployedtodetermine()theequilibriumphasespresentinthealloyataspecifiedtemperature,alongwiththecompositionandrelativeamountofeachphaseinthealloy.AStraightlineruleBLeverruleCCenterofgravityruleDTangentrule正確答案：ABC第18題Thevariable-temperaturesectionoftheternaryphasediagramiscategorizedinto().AIsometricsectionBEquilateralsectionCQuantitativesectionDHorizontalsection正確答案：AC第19題Thetemperature-variablesectionoftheternaryalloyphasediagramcananalyzethecrystallizationprocessofthealloyandcalculatetherelativecontentofthecrystallizedphases.()第20題Thereexistsatemperatureintervalforthefour-phasereactionintheternaryphasediagram.()第21題Ataspecifictemperature,whentwo-phaseequilibriumispresentinternaryalloys,thecompositionpointsofthealloyandthoseofthetwoequilibriumphasesmustresideonthesamestraightlinewithinthecompositiontriangle.Thisprincipleisreferredtoasthecollinearityruleorlinearlaw.()第22題Thedegreeoffreedominthethree-phaseequilibriumregionoftheternaryphasediagramiszero.()第23題Foranycomponentpointslocatedonalineparalleltoonesideofanequilateraltriangle,themassfractionratioofthetwocomponentsrepresentedbytheverticesatbothendsofthisparallellineisequal.()第24題Inanalloypositionedonastraightlinepassingthroughonevertexoftheconcentrationtriangle,theratiooftheothertwocomponentsremainsconstant.()第25題Intheverticalsectionofaternaryphasediagram,theliquidusandsoliduslinescanbeusedtorepresenthowthecompositionofliquidandsolidphaseschangeswithtemperatureduringthesolidificationofanalloy.()第26題Ataspecifictemperature,whentwo-phaseequilibriumoccursinaternaryalloysystem,thecompositionpointofthealloyandthecompositionpointsofthetwoequilibriumphasesmustlieonthesamestraightlinewithinthecompositiontriangle.Thisprincipleisknownastheruleofstraightlines.()第27題Foraknownalloyintwo-phaseequilibriumataconstanttemperature,ifthecompositionofonephaseisknown,thecompositionoftheotherphasewilllieontheextendedlinepassingthroughthetwoknowncomponentcompositions.()第28題Ifthecompositionofthetwoequilibriumphasesisknown,thenthealloycompositionislocatedonthelineconnectingthecompositionsofthetwoequilibriumphases.()第29題Theleverrulecanbeappliedtosectionswithvaryingtemperatures.()第30題Theleverrulecannotbeappliedtoisothermalsections.()ChapterVIItest第1題Aslipsystemiscomposedofaslipplaneand().ASlipdirectionBSlipvectorCSlippositionDSlipdisplacement第2題Thereare()slipsystemsinaface-centeredcubiclattice.A8B12C6D9第3題Sliptypicallyoccursalongthecrystalplanesandorientationsin()withinthecrystal.AClose-packedarrangementBAnyCConsiderationofthecrystalstructureisnecessary第4題Mechanicalpartsaremostlyin()undernormalworkingconditions.AElasticdeformationstateBPlasticdeformationstateCElastoplasticdeformationstate第5題Thedeformationofleadatnormaltemperaturebelongsto().AColddeformationBHotdeformationCElasticdeformation第6題Postmetalplasticdeformation,crystaldefects().AIncreaseBDecreaseCNotcertainDRemainunchanged第7題Theaccuratedescriptionofstructuralchangesinmetalspostplasticdeformationis().ADeformationBFragmentationCTextureDDeformation,fragmentation,andtexture第8題Whentheextentofmetalplasticdeformationissubstantial,itresults