Cu-0.36Cr-0.03Zr合金热压缩过程动态再结晶动力学研究【中文8800字】
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Cu-0.36Cr-0.03Zr合金热压缩过程动态再结晶动力学研究【中文8800字】,cu,cr,zr,合金,压缩,紧缩,过程,进程,动态,再结晶,动力学,研究,钻研,中文
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2698VOLUME266JUNE2017JOURNALOFMATERIALSENGINEERINGANDPERFORMANCEDYNAMICRECRYSTALLIZATIONKINETICSOFCU036CR003ZRALLOYDURINGHOTCOMPRESSIONGUOLIANGJI,FANGLIQIN,LIYUANZHU,QIANGLI,ANDLEILISUBMITTEDJUNE21,2016INREVISEDFORMDECEMBER24,2016PUBLISHEDONLINEMAY1,2017BASEDONCOMPRESSIONTESTSINTHETEMPERATURERANGEOF800950CANDTHESTRAINRATERANGEOF000120S21ONAGLEEBLE3500THERMOMECHANICALSIMULATOR,THEDYNAMICRECRYSTALLIZATIONDRXKINETICSOFCU036CR003ZRALLOYISDEVELOPEDBYFURTHERANALYSISOFTRUESTRESSSTRAINCURVESANDBYINVESTIGATINGMICROSTRUCTURESUNDERDIFFERENTDEFORMATIONCONDITIONSTHEKINETICSOFDYNAMICRECRYSTALLIZATIONISEXPRESSEDASTHEMODIEDJMAKMODEL,ANDEFFECTSOFVARYINGSTRAINRATEANDTEMPERATUREONTHEMODELPARAMETERS,INCLUDINGTHECRITICALSTRAIN,PEAKSTRAINANDMATERIALSCONSTANTKD,AREINVESTIGATEDTHECOMPLETEDRXGRAINSIZEISDESCRIBEDASAPOWERLAWFUNCTIONOFZENERHOLLOMONPARAMETERZ,ANDITAGREESWELLWITHTHEEXPERIMENTALDATAKEYWORDSCOMPRESSIONTESTS,CUCRZRALLOYS,DYNAMICRECRYSTALLIZATION,MICROSTRUCTURE1INTRODUCTIONWORKHARDENINGWH,DYNAMICRECOVERYDRVANDDYNAMICRECRYSTALLIZATIONDRXAREIMPORTANTPHYSICALMETALLURGYPHENOMENAINHOTWORKINGOFMETALMATERIALS,ANDDYNAMICRECRYSTALLIZATIONEASILYOCCURSFORMETALSANDALLOYSWITHLOWTOMEDIUMSTACKINGFAULTENERGY,SUCHASFCCMETALS,COPPERALLOYSANDNICKELALLOYSININDUSTRIALPRODUCTION,DYNAMICRECRYSTALLIZATIONISUSEDASANIMPORTANTMETHODTOIMPROVEMICROSTRUCTUREANDTOOBTAINNEANDHOMOGENOUSGRAINSTHEREFORE,ITISSIGNICANTTOREVEALTHEEVOLUTIONMECHANISMOFDYNAMICRECRYSTALLIZATIONOFMETALSORALLOYSFORMANUFACTURINGPARTSWITHTHENEMICROSTRUCTUREANDEXCELLENTMECHANICALPROPERTIESSOFARDYNAMICRECRYSTALLIZATIONBEHAVIORSOFMETALSORALLOYSHAVEBEENEXTENSIVELYSTUDIED,ANDSEVERALMODELSFORTHERECRYSTALLIZATIONKINETICSANDMICROSTRUCTUREEVOLUTIONWEREPROPOSEDREF14THESEMODELSCANBEMAINLYDIVIDEDINTOTWOCATEGORIESPHENOMENOLOGICALMODELANDPHYSICALLYBASEDINTERNALVARIABLEMODELPHENOMENOLOGICALMODELDESCRIBESTHEEVOLUTIONOFTHERECRYSTALLIZATIONVOLUMEINTHEFORMOFTHEAVRAMIEQUATION,INWHICHPARAMETERSTOBEDETERMINEDAREUSUALLYREPRESENTEDASAFUNCTIONOFINITIALGRAINSIZE,TEMPERATURE,STRAINANDSTRAINRATEPHENOMENOLOGICALMODELSHAVEBEENWIDELYADOPTEDBYCOMMERCIALFEMSOFTWARE,SUCHASFORGEANDDEFORM3D,TOSIMULATERECRYSTALLIZATIONEVOLUTIONOFMETALSORALLOYSLOYDAETALREF5ESTABLISHEDKINETICSMODELSOFDYNAMICRECRYSTALLIZATIONDRX,METADYNAMICRECRYSTALLIZATIONMDRX,STATICRECRYSTALLIZATIONSRXANDGRAINGROWTHFORANIFEBASEDGUOLIANGJI,FANGLIQIN,LIYUANZHU,ANDQIANGLI,SCHOOLOFMATERIALSSCIENCEANDENGINEERING,HENANPOLYTECHNICUNIVERSITY,JIAOZUO454000,CHINAANDLEILI,SCHOOLOFMECHANICALENGINEERING,SHANGHAIDIANJIUNIVERSITY,SHANGHAI201306,CHINACONTACTEMAILSJICHENMIAO126COMANDLEILI_HPU163COMSUPERALLOYANDEVALUATEDTHEAVERAGEGRAINSIZEANDRECRYSTALLIZATIONFRACTIONOFTHENIFEBASEDSUPERALLOYDURINGTHEROTARYFORGINGPROCESSBYIMPLEMENTINGTHEPREVIOUSPHENOMENOLOGICALMODELSINTOTHECOMMERCIALPLATFORMDEFORM3DCHENETALREF6PROPOSEDTHESEGMENTEDKINETICSMODELSTODESCRIBEDYNAMICRECRYSTALLIZATIONBEHAVIOROFATYPICALNICKELBASEDSUPERALLOYDURINGHOTDEFORMATION,ANDTHEPROPOSEDSEGMENTEDMODELSCANGIVEANACCURATEANDPRECISEESTIMATIONOFTHEVOLUMEFRACTIONSOFDRXFORTHESTUDIEDSUPERALLOYBASEDONTHEINTERNALVARIABLEMODELOFDRXTHATDESCRIBESDISLOCATIONDENSITYEVOLUTION,NUCLEATIONANDGRAINGROWTH,THECELLULARAUTOMATACAAPPROACHCANREPRESENTTHEGROWTHKINETICSANDMICROSTRUCTUREEVOLUTIONINTHETIMEANDSPACESCALEREF7CAALGORITHMFORRECRYSTALLIZATIONUSESSTATEVARIABLESSUCHASDISLOCATIONDENSITYTOCREATEMOREREALISTICREPRESENTATIONSOFRECRYSTALLIZATIONKINETICSREF8,ANDWHETHERDRXGENERALLYTAKESPLACECANBEJUDGEDBYCOMPARINGTHEDISLOCATIONDENSITIESINTHEGRAINBOUNDARIESWITHACRITICALDISLOCATIONDENSITYREYESETALREF9SUCCESSFULLYMODELEDDRXOFINCONEL718ALLOYBYUSEOFTHECELLULARAUTOMATAMETHOD,ANDTHEINUENCEOFLOCALCHANGESOFINITIALGRAINWITHFULLYANDPARTIALRECRYSTALLIZEDMICROSTRUCTURESWASSIMULATEDBYCAANDCOMPAREDWITHISOTHERMALHOTCOMPRESSIONRESULTSLIUETALREF10STUDIEDTHEDYNAMICRECRYSTALLIZATIONBEHAVIOROFINCONEL718ALLOYBYEXPERIMENTSANDCELLULARAUTOMATONMODELANDFOUNDTHATTHEDRXGRAINSGRADUALLYBECOMEHOMOGENEOUSWHENTHEVOLUMEFRACTIONOFDYNAMICRECRYSTALLIZATIONISINCREASEDCHENETALREF11INVESTIGATEDTHEDYNAMICRECRYSTALLIZATIONINAUSTENITICSTAINLESSSTEELUSINGCELLULARAUTOMATONMETHODHUANGETALREF12REVIEWEDTHEDYNAMICRECRYSTALLIZATIONDRXMECHANISMSOCCURRINGINDIFFERENTTHERMOMECHANICALPROCESSINGCONDITIONSFORVARIOUSMETALLICMATERIALSITINCLUDESTHEFOLLOWINGTHREECATEGORIESDISCONTINUOUSDYNAMICRECRYSTALLIZATIONDDRX,CONTINUOUSDYNAMICRECRYSTALLIZATIONCDRXANDGEOMETRICDYNAMICRECRYSTALLIZATIONGDRXCHENANDLINREF13INVESTIGATEDTHEEVOLUTIONOFDYNAMICRECRYSTALLIZEDDRXGRAINANDDISLOCATIONSUBSTRUCTUREOFANICKELBASEDSUPERALLOYITISFOUNDTHATTHEDISLOCATIONSUBSTRUCTUREISALSOVERYSENSITIVETOTHEDEFORMATIONDEGREE,STRAINRATEANDDEFORMATIONTEMPERATUREWITHTHEINCREASEINJOURNALOFMATERIALSENGINEERINGANDPERFORMANCEVOLUME266JUNE20172699DEFORMATIONDEGREE,THEEVOLUTIONOFDISLOCATIONSUBSTRUCTURECANBECHARACTERIZEDASHIGHDISLOCATIONDENSITYDISLOCATIONNETWORKSUBGRAINDRXGRAINLINETALREF14INVESTIGATEDMICROSTRUCTUREEVOLUTIONDURINGDRXOFATYPICALNICKELBASEDSUPERALLOYITISFOUNDTHATTHEMICROSTRUCTURALCHANGESINDICATETHATBOTHCONTINUOUSDYNAMICRECRYSTALLIZATIONC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DYNAMICRECOVERYANDDYNAMICRECRYSTALLIZATIONASSHOWNINFIG6,THECURVEMARKEDAREPRESENTSTHETRUEWORKHARDENINGANDDRVBEHAVIOROFMETALMATERIALS,ORTHEASSUMEDWORKHARDENINGANDDRVBEHAVIOROFMETALMATERIALSINWHICHTHEREOCCURWORKHARDENING,DRVANDDRXSIMULTANEOUSLYRRECREPRESENTSTHEOWSTRESSOFMETALMATERIALSATTRIBUTABLETOWORKHARDENINGANDDRVTHECURVEMARKEDBREPRESENTSTHETRUEWORKHARDENING,DRVANDDRXBEHAVIOR,ANDITSSTAGEIIISCONSIDEREDTOBETHENETRESULTOFTHESIMULTANEOUSOPERATIONOFWORKHARDENINGANDDRVANDDRXREF34RDRXREPRESENTSTHEOWSTRESSINTHESTAGEII,ANDTHEDIFFERENCEDRBETWEENRDRXANDRRECISTHENETSOFTENINGDIRECTLYATTRIBUTABLETODRXVOLUMEFRACTIONOFDRXREF2931CANALSOBEREPRESENTEDFIG7CURVEOFHVSRATATEMPERATUREOF900CANDASTRAINRATEOF01S1HOLLOMONPARAMETERZINANEXPONENTTYPEEQUATIONREF3234ASFOLLOWSZE_EXPQEQ4WHERERISTHEUNIVERSALGASCONSTANT8314JMOL1K1TISTHEABSOLUTETEMPERATUREKQISTHEACTIVATIONENERGYJMOL1E_ISSTRAINRATES1MOREOVER,ZCANBEFURTHEREXPRESSEDASAFUNCTIONOFSTRESSINTERMSOFTHEPOWERLAW,THEEXPONENTIALLAW,ORTHEHYPERBOLICSINELAWASFOLLOWSZAFREQ512EQ6ASXDRRSATRSSEECEQ3SINHARFORALLRWHEREA,A,B,NANDNARETHEMATERIALCONSTANTS,AB/N,ANDRISUSUALLYCHARACTERISTICSTRESSES,SUCHASTHEPEAKSTRESSTHECRITICALSTRAINEC,PEAKSTRAINEP,SATURATIONSTRESSRSATANDSTEADYSTRESSRSSNEEDTOBEDETERMINEDRSTLYTOESTABLISHTHEKINETICSMODELOFDRXASSHOWNINFIG6,THEPEAKSTRAINEPANDPEAKSTRESSRPANDSTEADYSTRESSRSSCANBEOBTAINEDDIRECTLYFROMTRUESTRESSSTRAINCURVESHOWEVER,DIRECTDETERMINATIONOFCRITICALSTRAINECISDIFCULT,ANDITCANBEATTAINEDWHENTHEVALUEOF|DH/DR|,WHERESTRAINHARDENINGRATEHDR/ANDSTEADYSTRESSHERE,WEUSETHEPEAKSTRESSRPTOCALCULATETHEDEFORMATIONACTIVATIONENERGYAFTERTHEVALUEOFABEINGEVALUATED,REGRESSIONANALYSISDETERMINESTHEDEFORMATIONACTIVATIONENERGYASQ4326KJ/MOLCALCULATIONOFQHASBEENELABORATEDINREF30SOTHEEXPRESSIONOFZENERHOLLOMONPARAMETERZISGIVENASFOLLOWS4326105DE,REACHESTHEMINIMUM,WHICHCORRESPONDSTOANINECTIONOFDR/DEVERSUSRCURVEREF35THEN,SATURATIONSTRESSRSATCANZE_EXPRTEQ7BEDETERMINEDASTHEHORIZONTALINTERCEPTOFTHETANGENTLINEOFHRPLOTTHROUGHTHEINECTIONPOINTASANEXAMPLE,FIG7SHOWSTHEPLOTOFHVERSUSRATATEMPERATUREOF900CANDASTRAINRATEOF01S1,FROMWHICHITISEASYTODETERMINETHEVALUESOFTHECRITICALSTRESSRCANDTHECRITICALSTRAINEC,THEPEAKSTRESSRPANDTHEPEAKSTRAINEP,SATURATIONSTRESSRSATANDTHESTEADYSTATESTRESSRSSWHENMETALMATERIALSAREDEFORMEDINSOMEPROCESSPARAMETERS,STEADYOWSTRESSMAYNOTAPPEARINTHETRUESTRESSSTRAINCURVES,SOONECANEXTRAPOLATETHECURVEOFHVERSUSRATTHEENDTOOBTAINTHESTEADYSTRESSTHEEFFECTOFTEMPERATUREANDSTRAINRATEONHOTDEFORMATIONBEHAVIOROFMETALMATERIALSCANBEREPRESENTEDBYZENERFOREACHOFTRUESTRESSSTRAINCURVESCHARACTERISTICOFDRX,ONECANOBTAINACRITICALSTRAINANDAPEAKSTRAINFIGURE8SHOWSTHATTHEREEXISTSALINEARRELATIONBETWEENLNECANDLNZSO,THECRITICALSTRAINECCANBEREPRESENTEDASAFUNCTIONOFZENERHOLLOMONPARAMETERZASFOLLOWSEC1622105Z01975EQ8FIGURE9SHOWSTHATTHEREEXISTSALINEARRELATIONBETWEENLNEPANDLNZSO,THEPEAKSTRAINEPCANBEREPRESENTEDASAFUNCTIONOFZENERHOLLOMONPARAMETERZASFOLLOWSEP00154Z0063EQ9
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