第1題Thefollowingsymbolsareusedtoindicatetheplasticmechanicalpropertiesoftheindexis().ARLBK

CZ

DRm第2題Doingfatiguetest,thespecimenloadis().

AStaticload

BImpactload

CAlternatingloadDDynamicload第3題

Itisnotsuitableforthefinishedproductandthesurfaceofthethinlayerhardnesstestmethodis().A

Brinellhardness

BRockwellhardnessCVickershardnessDAllofthesecanbe第4題Theindexformeasuringthetenacityofametallicmaterialis().

AThenumberofcyclesunderalternatingload

BAbsorptionofenergyCScratchsizeDImpactnotchsize第5題

Theabilityofmetallicmaterialtoresistobjectsharderthanitpressedintoitssurfaceis().

AStrength

B

Tenacity

CPlasticity

DHardness第6題Determinethestrengthofthematerialwiththetensiletest,thespecimenissubjectedtotheloadis().

AAlternatingloadB

Staticload

CImpactload

D

Dynamicload第7題

Whatmechanicalpropertyofametalisindicatedbyitsgoodwearresistance()

AStrength

BPlasticity

C

HardnessD

Tenacity第8題ThefollowingpartscanbeusedBrinellhardnessHBWtodeterminethehardnessvalueis().

AHardenedshaft

BCementedcarbideblade

C

Castironbase

DCarburizedhardenedgears第9題Theabilityofmetallicmaterialstowithstandaninfinitenumberofcycleswithoutfractureunderalternatingloadisknownas().A

FatiguestrengthB

Hardness

C

Strength

DPlasticity第10題

Inthetensiletest,tensilespecimenscanwithstandthemaximumnominalstressbeforepullingoffis()

AYieldstrength

BTensilestrength(correctanswer)

CCompressivestrength

DFlexuralstrength第11題1.

Duringstressreliefannealing,theorganizationoftherigiddoesnotchange.()第12題Metalmaterialscommonlyusedinmachinerymanufacturingaremainlypuremetals.()第13題Groupelementsarethephasesthatmakeupanalloy.()第14題Asubstitutionalsolidsolutioncanbeformedonlywhenthetwoatomsareofsimilarsizeandthepropertiesoftheatomsaremoresimilar.()

第15題Ferriteisasolidsolutionwithsolidsolutionstrengthening,soitspropertiesarehardandbrittle.()第1題Inmildsteeltensiletest,thefirstexperiencestageis().

AElasticdeformationstage

B

Yieldstage

CStrengtheningstageDNeckingdownstage第2題Theabilityofmetallicmaterialstowithstandaninfinitenumberofcycleswithoutfractureunderalternatingloadisknownas().AFatiguestrength

BHardness

C

Strength

D

Plasticity第3題

Accordingtonationalregulations,from2013onwards,carswillbeguidedtoscrapafterexercising600,000kilometers,whichismainlytoconsiderthe()ofmaterials.

AStrengthB

FatiguestrengthCHardness

DTenacity第4題Itisnotsuitableforthefinishedproductandthesurfaceofthethinlayerhardnesstestmethodis().ABrinellhardnessBRockwellhardnessCVickershardnessDAllofthesecanbe第5題Doingfatiguetest,thespecimenloadis().AStaticloadBImpactloadCAlternatingloadDDynamicload第6題

Solidsolution,canretainthecrystallatticestructureoftheelementwithmorecontentiscalled______,whilethecrystallatticestructuredisappearstheelementiscalled______.()ACompound/solidsolutionB

Solidsolution/compoundCSolvent/soluteDSolute/solvent第7題

Thecorrectstatementoffollowingstatementaboutalloysis______.()A

ThegroupelementsofthealloycanalsobecalledthephasestructureofthealloyBhephasestructureofthealloydeterminestheperformanceofthealloy.CSolidsolutionisoneofthebasicphasestructureofalloys.

DThegroupelementsofalloysareusuallystablecompounds.

第8題Thecorrectstatementoffollowingstatementaboutalloysis______.()AThegroupelementsofalloysareusuallystablecompounds.

BThebinaryalloyiscomposedoftwogroupelements.C

Thegroupelementsofalloysdeterminethepropertiesofalloys.DThegroupelementsofalloyscanalsobecalledthephasestructureofalloys.

第9題Thewrongstatementoffollowingstatementaboutalloysis______.()AThegroupelementsofalloyscanbestablecompoundsBThegroupelementsofalloysareusuallypureelements.CThegroupelementsofalloyscanbemixtures.DThephasestructureofalloyshavesolidsolutionsandmetalliccompound.

第10題Inordertogetfinermetalgrains,theproductioncanbeusedtoincreasethecondensatedepressionandothermeasures,forlargercastings,thecondensatedepressionshouldbe______.()ALarger

BSmallerC

ShouldnotbetoolargeDShouldnotbetoosmall

第11題Thecharacteristicsofmetalliccompoundsare

hardandbrittle,andthepropertiesofledeburitearealsohardandbrittle,soledeburitebelongstometalliccompounds.()第12題Theinterstitialsolidsolutionformedwhencarbonisdissolvedin?-Feiscalled“austenite”andisdenotedbythesymbolA.()第13題Austeniteexistsabove727°Candisanimportanthigh-temperaturephaseinironcarbonalloys,withlowstrengthandhardness,butgoodplasticityandtenacity,andiseasilyforgedandshaped.()第14題

Ironcarbonalloysaredividedintoingotironandsteel.()第15題Hypoeutectoidsteelwc=0.77％()ChapterOperation第1題Inordertogetfinermetalgrains,measuressuchas______,______andadditionalvibrationcanbeused.()AAppropriatereducethecondensatedepression,metamorphictreatmentB

Appropriateincreasethecondensatedepression/metamorphictreatment

CAppropriateincreasethecondensatedepression/metamorphictreatment

DAppropriatereducethecondensatedepression/metamorphictreatment

第2題Whenpuremetalscrystallize,thefastertherateofcooling,theactualcrystallizationtemperaturewillbe

.()AHigherB

Lower

CClosertothetheoreticalcrystallizationtemperature

DNochange第3題

Themainreasonforsolidsolutionstrengtheningofalloysis().ALatticetypehaschangedB

Grainrefinement

CLatticedistortion第4題.Thebasicreasonforsolidsolutionstrengtheningofthealloyis().A

LatticetypechangesB

Grainthinning

C

Grainthinning

D

Grainthinning

第5題Accordingtonationalregulations,from2013onwards,carswillbeguidedtoscrapafterexercising600,000kilometers,whichismainlytoconsiderthe()ofmaterials.AStrengthBFatiguestrengthCHardnessDTenacity第6題Theabilityofmetallicmaterialtoresistdeformationanddamageunderstaticloadis().AStrengthBHardnessCPlasticityDTenacity第7題Generally,whentheimpacttenacityofamaterialisgreater,itstenacityis()ABetterBWorseCNoeffectDHardtodetermine第8題Thefollowingisnotthemechanicalpropertiesofmetalsis().AStrengthBHardnessCTenacityDPressuremachiningproperty第9題Withdiamondconeasapressureheadcanbeusedtotest()ABrinellhardnessBRockwellhardnessCVickershardnessDAlloftheabove第10題Thetenacityofametalusually()astheloadingrateincreases,thetemperaturedecreases,andthedegreeofstressconcentrationincreases.AGetbetterBGetworseCNoeffectDDifficulttojudge第11題

Pearlitecontains6.69%carbon.()第12題Themechanicalpropertiesofpearliteareintermediatebetweenferriteandcementite.()

第13題Intheselectionofmaterials,ifitisnecessarytochooseasteelwithgoodplasticityandtenacity,asteelwithlowcarboncontent(mildsteel)shouldbeselected.()

第14題Ingeneral,carbonsteelhardeningwithoil,alloysteelhardeningwithwater.()第15題Dualmediumhardeningistheaustenitizationofsteel,firstimmerseinaweakcoolingcapacityofthemedium,beforethesteelhasnotreachedthetemperatureofthehardeningmediumthatistakenout,immediatelyimmersedinanotherstrongcoolingcapacityofthemediumtocool.()ChapterOperation第1題ThefollowingpartscanbeusedBrinellhardnessHBWtodeterminethehardnessvalueis().AHardenedshaftBCementedcarbidebladeCCastironbaseDCarburizedhardenedgears第2題Whatmechanicalpropertyofametalisindicatedbyitsgoodwearresistance()AStrengthBPlasticityCHardnessDTenacity第3題Determinethestrengthofthematerialwiththetensiletest,thespecimenissubjectedtotheloadis().AAlternatingloadBStaticloadCImpactloadDDynamicload第4題Theabilityofmetallicmaterialtoresistobjectsharderthanitpressedintoitssurfaceis().AStrengthBTenacityCPlasticityDHardness第5題Generally,whentheimpacttenacityofamaterialisgreater,itstenacityis()ABetterBWorseCNoeffectDHardtodetermine第6題Theabilityofmetallicmaterialstowithstandaninfinitenumberofcycleswithoutfractureunderalternatingloadisknownas().AFatiguestrengthBHardnessCStrengthDPlasticity第7題Inmildsteeltensiletest,thefirstexperiencestageis().AElasticdeformationstageBYieldstageCStrengtheningstageDNeckingdownstage第8題Theabilityofmetallicmaterialstowithstandaninfinitenumberofcycleswithoutfractureunderalternatingloadisknownas().AFatiguestrengthBHardnessCStrengthDPlasticity第9題Actualmetalcrystalsexistalargenumberofcrystaldefects,accordingtoitsmorphology,therearemainly______,______and______.()APointdefect/edgedislocation/linedefect

BPointdefect/linedefect/facedefectCLinedefect／facedefect／subboundaryDFacedefect／subboundary／crystaldefect第10題Thephasestructuresinthealloyare

().A

Solidsolutions,compounds

BSolidsolutions,mechanicalmixturesCSolidsolutions,mechanicalmixturesDSolidsolution,compounds,mechanicalmixtures第11題TheheatingtemperatureofsteeltemperingisbelowAc1,sothereisnoorganizationalchangeinthetemperingprocess.()第12題nducedsurfacehardening,thedepthofthehardenedlayerdependsonthecurrentfrequency;thelowerthefrequency,theshallowerthehardenedlayer;conversely,thehigherthefrequency,thedeeperthehardlayer.()第13題Theeliminationofreticulatedcementiteinhypereutectoidsteelcanbedonebycompleteannealing.()第14題Forfire-sensitivematerials,fastcooling(wateroroilcooling)canbeusedtoavoidembrittlement.()

第15題

Thehigherthetemperingtemperatureofthehardenedsteel,thehigherthestrengthandhardnessaftertempering.()ChapterOperation第1題Thecrystallizationprocessofmetalsinvolves______and______.()A

Crystalnucleuscontinuestoform/crystalnucleusgrowthBGrain/grainboundaryCGrainboundary/subboundaryD

Crystalnucleus/crystalnucleusgrowth

第2題Afterthemetaliscrystallized,thethicknessofitsgrainsisrelatedtothecrystallizationof______.()ANucleationrateandnucleationspeed

BNucleationrateandnucleationspeed

CCondensatedepressionDGrainsizeandcrystalnucleusgrowthspeed

第3題Aftercrystallizationofthesamemetal,theonewithfinergrainsis______.()

AHigherstrengthandpoorerplasticityBLowerstrengthandpoorerplasticity

C

Lowerstrengthandbetterplasticity

D

Lowerstrengthandbetterplasticity

第4題Inthetensiletest,tensilespecimenscanwithstandthemaximumnominalstressbeforepullingoffis()AYieldstrengthBTensilestrength(correctanswer)CCompressivestrengthDFlexuralstrength第5題Theindexformeasuringthetenacityofametallicmaterialis().AThenumberofcyclesunderalternatingloadBAbsorptionofenergyCScratchsizeDImpactnotchsize第6題Thefollowingsymbolsareusedtoindicatetheplasticmechanicalpropertiesoftheindexis().ARLBKCZDRm第7題Thefollowingsubstancethatisnotacrystalis______.()ASteelB

OrdinaryglassC

GraphiteDTinbronze第8題Thewrongstatementoffollowingstatementaboutcrystalsis______.()AMostsolidsubstancesarecrystalsBMetalswithaface-centeredcubiclatticearegenerallybetterinplasticity.CThephysical,chemicalandmechanicalpropertiesofsinglecrystalsinalldirectionsarebasicallythesameDPureironhasthenatureofallotropictransformation.第9題Actualmetalcrystalsaremostly_____crystals,whosephysical,chemicalandmechanicalpropertiesshow______indifferentdirections.()ASingle/isotropicBSingle/anisotropic

CMulti/anisotropicD.Multi/isotropic第10題Themostbasic,independentsubstancethatmakeupanalloyiscalled______.()A

CompoundB

SolidsolutionC

ElementDGroupelement

第11題Themaximumhardeninghardnessofsteelmainlydependsonthecarboncontentofausteniteinthesteel.()第12題Aftersteelnitriding,ithashighhardnessandwearresistancewithouthardening.()

第13題Allormostofthecarbonofvermiculargraphitecastironexistsintheformofworm-likegraphite,whichisobtainedbyvermicularizingtreatment.()

第14題Metallicmaterialsaredividedintotwocategories:commonmetalsandnon-ferrousmetals.()第15題Accordingtodifferentimpuritycontentofindustrialpurecopper,itisdividedintoT1,T2,T3andT4fourcodes.()

ChapterOperation第1題Thevastmajorityofmetalsexistinthefollowing______form.()ABody-centeredcubiclatticeB

Face-centeredcubiclatticeCOrthorhomiclattice

DHexagonalclosepackedlattice.第2題Thewrongstatementoffollowingstatementaboutsolidsolutioninalloysis______.()A

Solidsolutioncanleadtosolidsolutionstrengtheningwhenthecontentofsoluteelementsinsolidsolutionisalittletoomuch.B

Solidsolutionsolutesolubilityinthesolventisbasicallyunchanged.CSolidsolutionisoneofthebasicphasestructureofthealloy.D

Solidsolutioninthesoluteandsolventmaybeinfinitelycompatible.第3題

Ifthepuremetalcrystallizationprocessintheliquid-solidtwo-phaseequilibriumcoexistencestate,thistimethetemperaturewillbe(B)thanthetheoreticalcrystallizationtemperature.()AHigher

BLowerCLowerDHighandlowfluctuation第4題Amongtheironandsteelmaterials,thematerialwiththelowestcarboncontentis,thematerialwithgoodcomprehensivemechanicalpropertiesandpearliticcompositionis,thematerialwiththehighestcarboncontentis.()Angotiron/eutectoidsteel/castironB.Castiron/steel/ingotironCHypoeutectoidsteel/eutectoidsteel/hypereutectoidsteelDFerrite/pearlite/cementite第5題Inordertoimprovethemachinabilityof10steel,usuallyused()heattreatment.ACompleteannealingBSpheroidizingannealingCStressreliefannealing第6題Thefollowingsteelthatisnotsuitableforsurfacehardeningis().A45B08FC65第7題Comparedwithinducedsurfacehardening,flamecasehardeningis().AMoreefficientBEasiertograspthedepthofthehardenedlayerCSimpleequipment第8題Thefracturecolorofcastironisdifferent,becausethepresenceformof()isdifferent.ACarbonBSulfurCManganeseDPhosphorus第9題Mostofthecarboninwhitecastironisintheformof().AFlakegraphiteBGraphiteCCementiteDLedeburite第10題Theincorrectstatementoffollowingstatementsontenacityis().ATenacityistheabilityofmetallicmaterialstoabsorbdeformationenergybeforefracture.BThesizeofthetenacityofmetallicmaterialsisusuallyusedtomeasuretheenergyabsorptionKindicators.CThepunchofpunchpressrequiressufficientstrength,plasticity,hardness,butalsohaveenoughtenacity.DThematerialwithgoodtenacityisgenerallybadplasticity.第11題Addingsilicon,copper,magnesium,manganese,zincandotheralloyingelementstopurealuminumtoformaluminumalloysthatcansignificantlyincreaseitsstrength.()第12題Accordingtothecompositionofaluminumalloyandthecharacteristicsoftheproductionprocess,aluminumalloyscanbedividedintosuperhardaluminiumalloyandforgingaluminumalloy.()第13題esistancebuttweldingisgenerallyusedonlyforweldmentswithsimpleendfaces,diameterslessthan20mmandlowstrengthrequirements.()第14題Groupelementsarethephasesthatmakeupanalloy.()第15題Theheatandelectricityconductivityofpurecopperisveryexcellent,secondonlytosilver,isindispensabletotheelectricalappliancesindustryandinstrumentationindustryconductive,thermallyconductivematerials.()

ChapterOperation第1題Itisnotsuitableforthefinishedproductandthesurfaceofthethinlayerhardnesstestmethodis().ABrinellhardnessBRockwellhardnessCVickershardnessDNoneoftheabovemethods第2題Thewrongstatementoffollowingstatementaboutcrystalsis______.()AMostsolidsubstancesarecrystals.BMetalswithaface-centeredcubiclatticearegenerallybetterinplasticity.CThephysical,chemicalandmechanicalpropertiesofsinglecrystalsinalldirectionsarebasicallythesame.DPureironhasthenatureofallotropictransformation.第3題The()ingraypigironistheelementthatshouldbelimited.ACarbonBSiliconCSulfurDPhosphorus第4題MetalmaterialwithgradeKTZ650-03belongsto().

AGraypigironBNodularcastironCVermiculargraphitecastironDMalleablecastiron第5題()belongstothematerialphysicalproperties.AStrengthBHardnessCThermalexpansionDCorrosionresistance第6題Inordertogetfinermetalgrains,measuressuchas______,______andadditionalvibrationcanbeused.()AAppropriatereducethecondensatedepression,metamorphictreatmentBAppropriateincreasethecondensatedepression/metamorphictreatmentCAppropriateincreasethecondensatedepression/metamorphictreatmentDAppropriatereducethecondensatedepression/metamorphictreatment第7題Afterthemetaliscrystallized,thethicknessofitsgrainsisrelatedtothecrystallizationof______.()ANucleationrateandnucleationspeedBNucleationspeedandnucleationareaCCondensatedepressionDGrainsizeandcrystalnucleusgrowthspeed第8題Thevastmajorityofmetalsexistinthefollowing______form.()AI+II+ⅢBII+Ⅲ+ⅣCI+II+ⅣDI+Ⅲ+ⅣEBody-centeredcubiclatticeII.Face-centeredcubiclatticeIII.OrthorhomiclatticeIV.Hexagonalclosepackedlattice.第9題Whenanalloycrystallizesfromaliquidtoasolidstate,theuniformsolidphaseformedwhenatomsofonegroupelementdissolveintothelatticeofanothergroupelementiscalled().ACrystalBSolidsolutionCCompoundDEutecticum第10題Thebasicreasonforsolidsolutionstrengtheningofthealloyis().A.晶格類型發(fā)生了改變ALatticetypechangesBGrainthinningCLatticedistortionDIsotropicisomerization第11題Thehardeningandheatingtemperaturesofsteelshouldallbeinthesinglephaseausteniteregion.()

第12題Castironisjustironandcarbon,itisanalloyofmainlyironandcarbon.()第13題Accordingtothedifferentpropertiesandmetallurgicalorganization,malleablecastironcanbedividedinto:blackheartmalleablecastironandpearliticmalleablecastiron.()

第14題Industrialpurecopperisoften0.1%-0.5%impurities(aluminum,oxygen,sulfur,phosphorus,etc.),makingtheconductivityofcopperimproved.()第15題Typeofelectrodeistheunifiedelectrodecodeintheweldingelectrodeindustry.TheJinJ422indicatesthatthestructuralsteelweldingelectrode,thetensilestrengthoftheweld

metalisnotlessthan42kgf/mm2,andthelastnumber2indicatesthetitanium-calcium-typefluxcasing,DCorACpowersupply.()ChapterOperation第1題()issuitablefortestingthehardnessofcementedcarbide,surfacehardeningsteelandsheetmetalhardnesstestmethod.ABrinellhardnessBRockwellhardnessCVickershardnessDAlloftheabovemethods第2題Thefollowingsubstancethatisnotacrystalis______.()ASteelBOrdinaryglassCGraphiteDTinbronze第3題Actualmetalcrystalsaremostly_____crystals,whosephysical,chemicalandmechanicalpropertiesshow______indifferentdirections.()ASingle/isotropicBSingle/anisotropicCMulti/anisotropicDMulti/isotropic第4題Inordertoimprovethemachinabilityof20steel,usuallyused()heattreatment.ACompleteannealingBSpheroidizingannealinCNormalizing第5題Comparedwithcarburizingparts,nitridingpartsis().AHigherhardnessindeeplayerBThickerindeeplayerCBettercomprehensivemechanicalproperties第6題Themetallicmaterialafterbreakelongationandsectionshrinkageishigher,itsplasticityismore().AGoodBMediumCPoor第7題Thermalrefiningtreatmentis()compositeheattreatmentprocess.AHardening+hightemperaturetemperingBHardening+mediumCHardening+lowtemperaturetempering第8題Mostofthecarboninbreakablecastironisintheformoffreeflocculent()existence.AFlakegraphiteBGraphiteCCementiteDLedeburite第9題The()ingraypigironisacontrolleduseofelement.ACarbonBSiliconCManganeseDPhosphorus第10題Malleablecastirongradebythreelettersplustwonumbers,ofwhichKTonbehalfofmalleablecastiron,HBZonbehalfoftheorganizationtype()malleablecastiron.ABlackheartBWhiteheartCPearliteDYellowheart正確答案：ABC第11題Asthenamesuggests,malleablecastironisforgeable.()

第12題Thepurealuminumofourcountrycanbedirectlyquotedfromtheinternationalfourcharacternamingsystemgrade,grade1A99,indicatingthatthepercentagecontentis99.99%ofthemodifiedaluminum().第13題Copperhasaspecialproperty-antimagnetic.()第14題Buttweldingisamethodofresistanceweldinginwhichtheweldmentisassembledintoalapjointandpressedbetweentwoelectrodes,usingresistanceheattomeltthebasemetalandformaweldingspot.()第15題Themodelofweldingelectrodeisthenationalstandardofweldingelectrodecode,thenumber"0"inE4303indicatesflatwelding()ChapterOperation第1題Accordingtothetensiletestprocessoftensiletestforceandelongationrelationship,drawnforce-elongationcurve(tensilediagram)candeterminethe()ofthemetal.

AStrengthandhardnessBStrengthandplasticityCStrengthandtenacityDPlasticityandtenacity第2題Rmindicatesthemaximumtensilestresstowhichthespecimenissubjected________.()ABeforepullingoffBAfterpullingoffCAtyieldingDBeforeelasticdeformation第3題Actualmetalcrystalsexistalargenumberofcrystaldefects,accordingtoitsmorphology,therearemainly______,____________.()APointdefect/edgedislocation/linedefectBPointdefect/linedefect/facedefectCLinedefect/facedefect/subboundaryDFacedefect/subboundary/crystaldefect第4題Ifthepuremetalcrystallizationprocessintheliquid-solidtwo-phaseequilibriumcoexistencestate,thistimethetemperaturewillbe()thanthetheoreticalcrystallizationtemperature.((___))()AHigherBLowerCequalDHighandlowfluctuation第5題Thephasestructuresinthealloyare().ASolidsolutions,compoundsBSolidsolutions,mechanicalmixturesC.化合物、機(jī)械混合物CCompounds,mechanicalmixturesDSolidsolution,compounds,mechanicalmixtures第6題The727°Clineontheironcarbonalloyphasediagramiscalled.()AEutectoidlineBSolidsolutionlineCEutecticlineDLatticetransitionline第7題Afterpenetration,partsgenerallyneedtobe()treatment,inordertoachievethepurposeofthesurfacehardandwear-resistant.AHardening+lowtemperaturetemperingBSurfacehardening+mediumtemperaturetemperingCThermalrefining第8題Usinghighcarbonsteelandcertainalloysteelforgingbillets,foundthatthehardnessistoohighwhenprocessing.Inordertomakeiteasytoprocess,()canbecarriedout.AHardeningBNormalizingCAnnealing第9題Using()canonlyeliminatethemoreseriousreticulatedcarbidespresentinlowalloycutlerysteel.ASpheroidizingannealingBCompleteannealingCNormalizing第10題Mostorallofthecarboningraypigironisprecipitatedby().AFlakegraphiteBGraphiteCCementiteDLedeburite第11題Whenthebasicelectrodewelding,slagspatterissmall,mobilityandcoverageisbetter,sotheweld

isbeautiful,thesensitivitytorust,greaseandmoistureisnotgreat,buttheburningofthealloyingelementsofthefluxcasing

intheweldingisgreater,andthecrackresistanceispoorer,anditissuitablefortheweldingofgeneralstructuralparts.()第12題Whenchoosingweldingelectrodes,shouldbebasedonthetensilestrengthofthebasematerial,accordingtotheprincipleofequalstrengthtochoosethesamestrengthlevelofweldingelectrodes.Forexample:thetensilestrengthofQ345isabout520MPa,sochooseJ502orJ506,J507weldingelectrodes.()第13題Carbondioxidegasshieldedweldingiscostlyandcomplicatedtooperate,andtheweldingqualityisgood.()第14題Metalmaterialscommonlyusedinmachinerymanufacturingaremainlypuremetals.()第15題Ironcarbonalloysareclassifiedintoingotiron,steel,andwhitecastiron.()ChapterOperation第1題Thecorrectstatementoffollowingstatementaboutalloysis______.()AThegroupelementsofthealloycanalsobecalledthephasestructureofthealloy.BThephasestructureofthealloydeterminestheperformanceofthealloy.CSolidsolutionisoneofthebasicphasestructureofalloys.DThegroupelementsofalloysareusuallystablecompounds.第2題Thecorrectstatementoffollowingstatementaboutalloysis______.()AThegroupelementsofalloysareusuallystablecompounds.BThebinaryalloyiscomposedoftwogroupelements.CThegroupelementsofalloysdeterminethepropertiesofalloys.DThegroupelementsofalloyscanalsobecalledthephasestructureofalloys.第3題Thewrongstatementoffollowingstatementaboutalloysis______.()AThegroupelementsofalloyscanbestablecompounds.BThegroupelementsofalloysareusuallypureelements.CThegroupelementsofalloyscanbemixtures.DThephasestructureofalloyshavesolidsolutionsandmetalliccompound.第4題Themostbasic,independentsubstancethatmakeupanalloyiscalled______.()ACompoundBSolidsolutionCElementDGroupelement第5題Aftercrystallizationofthesamemetal,theonewithfinergrainsis______.()AHigherstrengthandpoorerplasticityBLowerstrengthandpoorerplasticityCLowerstrengthandbetterplasticityDHigherstrengthandbetterplasticity第6題Thewrongstatementoffollowingstatementaboutsolidsolutioninalloysis______.()ASolidsolutioncanleadtosolidsolutionstrengtheningwhenthecontentofsoluteelementsinsolidsolutionisalittletoomuch.BSolidsolutionsolutesolubilityinthesolventisbasicallyunchanged.CSolidsolutionisoneofthebasicphasestructureofthealloy.DSolidsolutioninthesoluteandsolventmaybeinfinitelycompatible.第7題α-Feisironwith()lattice.()ABody-centeredcubicBFace-centeredcubicCHexagonalclosepacked第8題Themainreasonforsolidsolutionstrengtheningofalloysis().ALatticetypehaschangedBGrainrefinementCLatticedistortion第9題Theorganizationofsteelinthetemperingtothetreatmentis().ATemperedmartensiteBTemperedsorbiteCTemperedtroostite第10題Whenthesteelisheated,thebasisforjudgingtheoverburningphenomenonis().ASurfaceoxidationBOxidationormeltingofaustenitegrainboundaryCCoarseaustenitegrains第11題Thepurposeofgraypigironsurfacehardeningistoimprovethesurfaceplasticityandwearresistanceofgraypigironparts.()第12題Afterpouredwithspheroidizedcastironliquid