289-paper-激光焊接動態(tài)試驗

1、EvaluatingStrengthToughnessPropertiesofLaserWeldmentbyDynamicTestingFANGJian(BaosteelResearchInstituteBaoshanIron&SteelCo.Ltd.Shanghai201900China)Abstract:Thestrengthtoughnesspropertiesofalaserbeamweldedjointfromhotrolle

2、dDP600steelplatewereevaluatedbyVickershardnessinstrumentedpyimpacttesting.BasedontheimpactfcedisplacementcurveCriticalCrackLengthi.e.CCLdynamiccrackextensionresistancecurvei.e.J?aweredetermineddescribingtheweldingjoint’s

3、crackinitiationtoughnesscrackgrowthbehavirespondingtothedynamicloading.FurthermetearingmodulederivedfromtheslopeofJ?acurvewasdiscussedwiththelinktothematerialmicrostructuremechanismaffectedbythethermodynamicprocessoflase

4、rbeamwelding.Keywds:laserbeamweldinginstrumentedpyimpactdynamictesting1.IntroductionDuetotheconvenientmanufacturingprocessacquiredexcellentmechanicalpropertiesofweldingjointlaserbeamweldingtechniquehasbeenwidelyusedinthe

5、automotiveshipbuildingoiltransptationpipelineindustrysofar.Incommonthemechanicalperfmanceofmetallicmaterialmaybeaffectedbythethermodynamicfactcrespondingtothekindsofweldingprocess.MeoverItistakenintomemeaccountthatthemec

6、hanicalpropertiesofstructuralcomponentconsistingofbasalmaterialjointpartshouldbeassuredevenundertheserviceconditionwiththerequirementofstructuralintegritysafetyfautoframewkshiphulldesign.ItwasreptedasanexampleinThyssenKr

7、uppCo.AHSSincludingDualPhase(DP)TransfmationInducedPlasticity(TRIP)steelswiththeirLaserweldingcomponentsshouldbeevaluatedwithlowtemperaturedynamicloadingconditiontosimulatethestrengthtoughnessresponseinservice1.Besidesco

8、nventionaltensilehardnessimpacttestingsomeothermodernexperimentaltechniquesshouldbeappliedfacterizationofweldingjointscomprisingtemperaturefactintermediatestrainrateloadingconditionwhichmaybeofpracticalvaluetoprocessopti

9、mizationmaterialionqualitysimulationoflaserbeamwelding.InthepresentwksubsizepyspecimenssampledfromvariouspartsoflaserweldingjointcomposedofthesamehotrolledDPsteelplatewerepreparedfinstrumentedimpacttesting.Combinedwithth

10、eElasticPlasticFractureMechanical(EPFM)analysisbyusingBAOSTEELexclusiveImpactPlus2.0theinfluenceoflaserweldingontothestrengthtoughnesspropertiesofDPsteelwereexperimentallyinvestigated.2.PrinciplesDerivedfromtheadvantageo

11、flowcostreliabilityofconventionalpytestinginstrumentedimpacttestingi.e.IITisbelievedasanindustrialdynamictestingmethodfevaluatingmaterialsresponsetodynamicloadingwithtemperaturevariation.Byrecding(3)20)(499.2aWBSFgyyd???

12、ConcerningthecrackpropagationfractureresistancepropertiesJ?acurvewasestablishedontheconceptof“KeyCurve”methodtoindicatethecontributionofenergyconsumptiontothestablecrackgrowthresistinginstabilityofcleavagefractureasEq.(4

13、)(5).(4)????plplpdBbkJ0(5)))((0211akPWWanpln??????3.ExperimentsSubsizepyspecimens(2.51055mm)weresampledfromthelaserbeamweldingjointcomposedoftwosameDP600hotrolledplatesteelwiththethicknessof3.7mm.Withtheaimtodistinguisht

14、hepropertiesofBaseMateriali.e.BMHeataffectingZonei.e.HAZWeldingAreai.e.WAVnotchofthespecimensweremachinedinthethicknessdirectionlocatedinthemarkedthreeareasrespectivelyasshowninFig.2.Instrumentedimpacttestingwascarriedou

15、tat20℃–40℃.FevaluationthestrengthoflaserweldingjointthedistributionofVickershardnesswasalsodeterminedonthetestingsurfaceperpendiculartotheweldingdirection.Figure2Laserweldingjointthespecimensampledfromtheplatefpyimpactte

16、sting.4.Resultsdiscussions4.1HardnessPropertiesTheboundaryofweldingareawasclearlymarkedbyacidcrosion.ThenthedistributionofhardnessonthetestingsurfaceperpendiculartotheweldingdirectionweredeterminedbymeansofVickersalongth