简介:309Lisakindofausteniticstainlesssteel.Thispaperdiscusses309L,whichwassmeltedandrolledinalab.Itsmicrostructuralcharacteristicsinstatesofas-cast,hot-rolling,cold-rollingandsolidsolutionwereinvestigatedrespectivelybyopticalmicroscope(OM).Itisfoundthat309Liscomposedofausteniteandresidualδ-ferriteundertheseconditions,andtheδ-ferritecannotbeeliminatedeasilybyheat-treatment.Itshotplasticityanddeformationresistancewereinvestigatedinaseriesofheatsim...
简介:Twothermo-mechanicalcontrolledprocesses(TMCP)includingcontrolledrollingandacceleratedcoolingareproposedfortheproductionofheavygaugeSUS304Lausteniticstainlesssteelplateswithdifferentstrengthsandothercharacteristics.BasedontherecrystallizationmechanismandcarbideprecipitationbehaviorofSUS304Lausteniticstainlesssteel,TMCPprovidesapowerfulmeanstocontrolthemicrostructureandprecipitationofthehotrolledsteelplatebythecontrolledrollingandacceleratedcoolingprocess.Thedislocationdensityandgrainsizearethemainfactorsindeterminingthestrengthofthestainlesssteelplates.Therefore,itisnecessarytostrictlycontrolthehotrollingparameters,includingparameterssuchasthefinishhotrollingtemperatureintherecrystallizationtemperatureregionandthetotalreductioninthenon-recrystallizationregion.Furthermore,inordertoavoidcarbideprecipitationandguaranteetheintergranularcorrosionresistanceofTMCPSUS304Lausteniticstainlesssteel,acriticalcoolingrateafterrollingisdetermined.
简介:FSWandTIGwereconductedon316Lstainlesssteel.Variationduringmicrostructureandpropertiesinjointsobtainedbydifferentweldingmethodswasstudied.TheresultsshowthattheeffectofseveremechanicalstirringandintenseplasticdeformationcreatafinerecrystallizedgrainintheweldingjointduringFSW.AsforTIG,thetemperatureofweldingjointexceedsthemeltingpointofweldedmaterialitself.Theentireweldingprocessbelongstothesolidificationofasmallmoltenpool;andthemicrostructureofthejointtakesonatypicalcastingstructure.Whentheweldingparameterswereselectedappropriately,theaverageultimatetensilestrengthofFSWjointscanreach493MPa,whichis83.6%ofbasemetal;theaverageelongationis52.1%ofbasemetal.TheaverageultimatetensilestrengthofTIGjointsis475MPa,whichis80.5%ofbasemetal;theaverageelongationis40.8%ofbasemetal.ThetensiletestofFSWjointsissuperiortotheTIGjoints.ThemicrohardnessofFSWjointcomparedtobasemetalandTIGjointhavingasignificantimprovement,whicharel95.5HV,159.7HVand160.7HV,respectively;grainrefinementstrengtheningplaysanimportantroleinenhancingthemicrohardness.TheelectrochemicalcorrosiontestsshowthatthejointofFSW316Lausteniticstainlesssteelhasagoodcorrosionresistance.
简介:TheFe-Ti-Nmateralloywaspreparedthroughthein-situreactionofnitrogengaswiththeFe-Timelt.ScanningelectronmicroscoperesultsshowthattheparticlesuniformlydistributedintheironmatrixwereTiN.ThedeliberatelypreparedFe-Ti-Nmasteralloywasemployedforthe409Lferriticstainlesssteelinanattempttorefinetheas-castsolidificationstructure.ItwasfoundthattheeffectivenessofFe-Ti-Nmasteralloyonrefiningoftheas-cast409Lferriticstainlesssteelwasaffectedbyadditionlevel,holdingtimeandmeltstemperature.Itwasfoundthattheaverageequiaxedgrainsizedecreasedfrom1503μmto303μm,theproportionofequiaxedgrainzoneincreasedfrom14%to100%withincreasingtheFe-Ti-Nmasteralloyadditionlevelto2.5%.Theproportionofequiaxedgraindecreasedfrom85%to4%asthesolidificationtemperatureincreasedfrom1803Kto1883K.Whentheholdingtimereachedto8min,thesolidificationstructuresof409Lferriticstainlesssteelshowextremepointsintheproportionofequiaxedgrain.Itisclearthatthegrainrefiningefficiencygraduallyfadeawaywiththeincreasingoftheholdingtimeattheverybeginning.However,whentheholdingtimecontinuestoincreaseandexceedstheextremepoint,thegrainrefiningefficiencyoftheFe-Ti-Nmasteralloyrecoveredtoacertaindegree.Theexperimentalresultsmentionedabovehavebeenanalyzedintermsofthermodynamics.Underappropriateconditions,theFe-Ti-Nmasteralloyusedforgrainrefinementofthesolidificationstructureof409Lferriticstainlesssteelmayhavegoodprospectsforindustrialapplications.
简介:本文主要讨论了酒钢储运质量检验过程管理系统与集团公司ERP系统接口的两种实现方法。