简介：

简介：

简介：TIGweldingwasusedtodepositCo-8.8Al-9.8W-0.2Bsuperalloyon304austenitestainlesssteel.Theformfactorofweld,dilutionratio,microhardness,microstructureanddistributionofalloyingelementswereinvestigated.Themicrostructureofcladdinglayerwasmainlyhypoeutectic.Theprimaryphaseswerecobalt-richsolidsolution.Theeutecticphasewascomposedofcobalt-richsolidsolution,Co6W6CandCoCx.Whentheboroncontentincreasedfrom0.2%to0.5%,thedilutionratiodecreased,theprimaryphasebecamecoarseandthemicrohardnessdecreased.Whentheboroncontentwasfrom0.5%to2%,thedilutionratioandmicrohardnessincreasedobviously,buttheprimaryphasewasrefined.ThehardphaseofCo-8.8Al-9.8Wbecamerefinedandtheamountwasraised,andtheperformanceofcladdinglayerwasimprovedwithappropriateboronincrease.

简介：

简介：

简介：

简介：

简介：ＴｈｅｒｍａｌｂｅｈａｖｉｏｒｏｆＢ４Ｃｐａｒｔｉｃｌｅｓｕｎｄｅｒｐｌａｓｍａａｒｃｐｏｗｄｅｒｓｕｒｆａｃｉｎｇｃｏｎｄｉｔｉｏｎ￥ＷＡＮＧＸｉｂａｏ；ＺＨＡＮＧＷｅｎｙｕｅ；ＬＵＴｏｎｇｌｉａｎｄＰＥＮＧＪｉｅ(ＨｅｂｅｉＵｎｉｖｅｒｓｉｔｙ...

简介：Anewhardfacingprocess,reactivebrazecoatingprocess(RBCC)wasstudied,and(TiC+Cr3C2)/FecompositecoatingswerepreparedbyRBCCusingcarbon,Cr3C2,iron,ferrochromiumandtitaniumpowderastherawmaterialsinvacuumbrazefurnace.TheresultsshowthatTiCisin-situsynthesizedinthecoatings.ThemethodsofintroducingCr3C2havegreateffectsonthedistributionofTiC.AddingCr3C2directlytotherawmaterialsforcoatings,fineTiCparticlesaggregateintodiscoidsparalleltothecoatingsurface,whereas,in-situsynthesizingCr3C2incoatings,theaggregationsofTiCarelumpish.Duringbrazecoating,Cr3C2particlesdirectlyaddeddissolveandprecipitatetobecomeneedle-shaped.Thecoatingshaveanevenandsmoothsurfaceandarecombinedwiththeirmildsteelsubstratesbyametallurgicalbonding.

简介：Basedonalargeamountofdissectionatweldedinterfaceandquantitativemicroscopicexaminationofweldedrate,thesuitablelimitgreyscalevaluewasdetermined,andtheweldedrateofsuperplasticsolid-stateweldinginterfaceofheterogeneoussteelwassystematicallystudiedbymeansofself-madeultrasonicC-scanningimaginginspectionsystem.Theexperimentalresultsshow:theweldedstateofsuperplasticsolid-stateweldinginterfaceofheterogeneoussteelcanbeconductedtobemoreaccurately,reliablyandquicklyinspectedbymeansofthissystem,andtheultrasonictestingresultsaregoodconsistentwithactualexaminationresultsoftheinterfacedefectivedistribution.Withintheextentofthesuitbleweldedrate,theweldedratein40Cr/T10Asuperplasticweldingprocesstestedbythissystemislinearwithitstensilestrengthofjoint.

简介：EffectsofalloyelementsonthemicrostructureandcrackresistanceofFe-C-Crweldsurfacinglayerwereinvestigated.Theresultsshowthatmicrostructuresofthelayermainlyconsistofcarbidesandaustenitematrix.IncreasingCandCrcontentsimpairthecrackresistanceofthelayerduetoincreasedamountofbrittlecarbides.TheadditionofNi,NborMoimprovesthecrackresistanceofFe-C-CrweldsurfacinglayerbyincreasingtheamountofausteniteandformingfineNbCorM7C3carbidesinthelayer.But,theexcessiveNb(>2.50wt%)orMo(>1.88wt%)impairsthecrackresistanceofthelayer,whichhasrelationwithincreasedcarbidesorcarbidecoarseningandaustenitematrixsolidsolutionstrengthening.ThepropercombinationofC,Cr,Ni,NbandMocanfurtherimprovenotonlythecrackresistanceofFe-C-CrweldsurfacinglayerbutalsotheerosionresistanceasaresultoffineNbCandM7C3carbidesdistributinguniformlyinaustenitematrix.Theoptimallayercompositionsare3.05wt%C,20.58wt%Cr,1.75wt%Ni,2.00wt%Nband1.88wt%Mo.

简介：Inthispaper,Ni-basedalloycompositecoatingreinforcedbyTi(C,N)particleswasfabricatedonthemildsteelthroughlasercladdingtechnology.Themicrostructureoflasercladdinglayerwasanalyzedbymeansofopticalmicroscopy(OM),X-raydiffraction(XRD)andscanningelectronmicroscopy(SEM).ThewearresistancetestofthecoatingwasevaluatedusinganM-2000tester.TheresultsshowedthattheNi-basedcompositecoatinghadanabilityofrapidsolidificationtoformdendriticcrystalsmicrostructureconsistingofTi(C,N)particulatesuniformlydistributedinthematrix.ItwasfoundthatsomeTi(C,N)particlesaresimilartoberoundinshape,andtheothersareirregular.LasercladdinglayerreinforcedbyTi(C,N)particulateswasfoundtopossessgoodwearresistanceproperty.

简介：

简介：