雨课堂学堂在线学堂云《Fundamental of Material Sciences（辽宁科技）》单元测试考核答案

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