简介：Inordertoutilizetheadvantageofoxidesinstainlesssteel,theformationoftitaniumnitride(TiN)andoxide(TixOy)inthe17CrsteelwasinvestigatedbythecalculationofthefreeenergyofreactionandthermodynamiccalculationwithThermo-calcsoftware.Theresultindicatesthatthecompetitivereactionbetweenthedissolved[O]andthedissolved[N]withthedissolved[Ti]inmoltensteelresultsindifferentprecipitationsequencesofTiNandTixOy.TheprimaryprecipitationofTiNrequiresalow[O]andtheprimaryprecipitationofTixOyrequiresalow[N].Theincreaseof[Ti]causesahigherprecipitationtemperatureofTiNandTixOyinbothTi-NandTi-Oalloysystems.Equilibriumrelationsof[Ti]vs[N]and[Ti]vs[O]showthatthesolubilityproductsfallwiththedecreaseofthetemperature,andthentheprecipitationoftheinclusionsbecomeseasier.IntheTi-Oalloysystem,ahigh[O]andalow[Ti]arefavorabletotheprecipitationofTi3O5,andahigh[Ti]contentandalow[O]favorabletotheTi2O3precipitation.

简介：316Lstainlesssteelcoatingswerepreparedbycoldgasdynamicspraying(CGDS)onacarbonsteel.Anewheaterofsprayedpowderswasaddedtothetraditionalfacility.Theresultsshowthatthecoatingqualityisobviouslyimproved,duetobetterinterfacebondingandreducedporosity.

简介：Martensiticstainlesssteelcontaining12%-18%Crhavehighhardnessduetohighcarboncontent.Thesesteelsarecommonutilizedinquenchingandtemperingprocessesforknifeandcutlerysteel.Thepropertiesobtainedinthesematerialsaresignificantlyinfluencedbymatrixcompositionafterheattreatment,especiallyasCrandCcontent.Comprehensiveconsideredthehardnessandcorrosionresistance,anewtypemartensiticstainlesssteel6Cr15MoVhasbeendeveloped.Thisstudyemphaticresearchestheeffectofheattreatmentprocessesonmicrostructureandmechanicalpropertiesof6Cr15MoVmartensiticstainlesssteel.Thermo-Calcsoftwarehasbeencarriedouttothermodynamiccalculation;opticalmicroscope（OM）,scanningelectronicmicroscope（SEM）andtransmissionelectronmicroscope（TEM）havebeencarriedouttomicrostructureobservation;hardnessandimpacttoughnesstesthavebeencarriedouttoevaluatethemechanicalproperties.Resultsshowthattheequilibriumcarbidein6Cr15MoVsteelisM23,C6carbide,andfinelydistributedofM23C6carbidescanbeobservedonannealedmicrostructureof6Cr15MoVstainlesssteel.6Cr15MoVmartensiticstainlesssteelhasawiderquenchingtemperaturerange,thehardnessvalueofsteel6Cr15MoVcanreachto60.8-61.6HRCwhenquenchedat1060-1100℃.Finelydistributedcarbideswillexistinquenchedmicrostructure,andeffectivelyinhabitthegrowthofaustenitegrain.Withtheincreasingofquenchingtemperature,thevolumefractionofundissolvedcarbideswilldecrease.Theexcellentcomprehensivemechanicalpropertiescanbeobtainedbyquenchedat1060-1100℃withtemperedat100-150℃,anditismainlyduetothehighcarbonmartensiteandfinegrainsize.Atthesetemperatureranges,thehardnesswillretainabout59.2-61.6HRCandtheCharpyU-notchimpacttoughnesswillretainabout17.3-20J.Themorphologyofimpactfracturesurfaceoftestedsteelissmalldimpleswithasmallamountofcleavageplanes.Theareaofcleavageplanesincreaseswiththeincreas

简介：Toexploretheapplicationofsevereplasticdeformationforgrainrefinementinsteelproduction,anewmethodcalledcontinuousfrictionalangularextrusion(CFAE)wasappliedtorefinethegrainofinterstitial-freesteel.Thedeformationwascarriedoutatroomtemperatureandindividualsheetspecimenswereprocessedindifferentnumberofpasses.Anoverallgrainsizeof200nmwasachievedafter8passesandtheproportionofhigh-angleboundariestothetotalboundarieswasmorethan60%.ThroughthecharacterizationofhighresolutionEBSD,X-raydiffraction(XRD)andhardnesstesting,thispaperdiscussedtheevolutionofmicrostructuresandtexturesduringdeformationandexploredthedevelopmentdirectionofthemethod.

简介：Withacomplicatedcomposition,largeproductionandseriousdamagetotheenvironment,stainlesssteelcold-rollingsludgehasbeenafocalpointconcerningenvironmentalprotectionforstainlesssteelenterprises.Uptonow,neitherathomenorabroadhaveanytechnologiescomeintobeingthatarenotonlyproper,safeandeconomicalbutalsosuitableforbulkutilizationofstainlesssteelcold-rollingsludge.Basedonthecharacteristicsofthestainlesssteelcold-rollingsludge,orthogonalexperimentswerecarriedoutonpelletproportioningandhigh-temperatureroasting,andmajormetallurgicalpropertiesofsludgepelletswerealsotested.Astheresultsshow,pelletswith30%additionofcold-rollingsludgearequalifiedregardingtheircompressivestrength,chemicalcompositionandmajormetallurgicalproperties.Noadverseimpacthappenstotheblastfurnaceoperationwhensludgepelletsaccountfor10%oftheblastfurnacerawmaterials.Therefore,thetechnicalrouteappliedinthispaperisprovedsimple,feasibleandenvironmentallyfriendlyforcold-rollingsludgetreatment.

简介：Air-atomizedfogcoolingisparticularlysuitablefortheafter-potcoolingofgalvanizedsteelstrips.Withairandwaterservingasworkingmedia,anexperimentalstudywasconductedontheatomizationcharacteristicsofanewly-developedcross-flowtypeoffognozzles.Thewaterfluxdistribution,sprayangleandpressureofwaterandairweremeasured.Theresultsshowthatthewaterdropletsizewassmallandinsensitivetothewaterflowrate.Thesprayanglewassmallandthewaterflowrateslightlyaffectedtheairpressureinthechamber.Anempiricalcorrelationbetweenthepressureinthechamberandthegasflowratewasobtainedforthepurposeofequipmentdesign.

简介：Coldrolledmartensiticsheetsteelsareachievingmoreandmoreapplicationsincar-makingbecauseoftheirultra-highstrengthandpotentialforweightreduction.Therelativelylowplasticityofultra-highstrengthmartensiticsteelsmightbeadrawbackfortheapplicationsintheaspectsofformingandsafetyprotectionfunctionandshouldbesignificantlynoted.A1500MPagradecoldrolledmartensiticsheetsteelhasbeenstudiedtoinvestigatethebendabilityat90degreebendingandimpacttoughnessaswellasfracturesurfacemorphologyatvarioustemperatures.Somediscussionshavebeenmadebasingupontheexperimentdatatogetsomeunderstandingontheperformanceofthematerialsundervariousconditionsandonhowtomakeuseofthiskindofultrahighstrengthsteelproperly.

简介：

简介：Thisstudyinvestigatesthecorrosionpropertiesof0Cr11Tiand0Cr11NbTiferriticstainlesssteels(FSS)forautomotiveexhaustsystems.Theresultsindicatethatthebasemetalandweldseamof0Cr11NbTisteelexhibitbetterintergranularandcondensatecorrosionresistantpropertiesbecausecarbonandnitrogenarestabilizedbyNbandTi,andtheprecipitationofCrcarbideisretardedingrainboundaries.

简介：Athree-dimensionalmathematicalmodelofthecombustionofpulverizedcoalandcokehasbeendeveloped.Themodelisappliedtotheblowpipe-tuyere-raceway-cokebedregioninanironmakingblastfurnaceinonecomputationaldomain,whichincludestwoparts:pulverizedcoalcombustionmodelintheblowpipe-tuyere-racewaycavityandthecoal/cokecombustionmodelinthesurroundingcokebed.Theeffectsofcoalpropertiesareexaminedcomprehensively,intermsofcoalburnoutandgasspeciesdistributions.TheresultsindicatethatusingacoaloffineparticlesizeorhighVMcontentcouldimproveburnoutandwouldaffectthegascompositionconsiderably.Theburnoutisexaminedintwoways:comparedwithburnoutalongtuyereaxis,burnoutovertheracewaysurfaceisamoresensitiveandsensibleparametertodescribetheamountofunburntcharenteringthecokebed.Themodelisusefulforexaminingtheflow-thermo-chemicalcharacteristicsofthepulverizedcoalinjection(PCI)processundervariousconditionsinablastfurnace.

简介：Superduplexstainlesssteels(SDSS)showcomplexprecipitationandtransformationbehaviorduringheattreatmentprocesses,whichaffectsbothmechanicalandcorrosionproperties.ThisreportpresentssomedataonthemicrostructuresthatdevelopafterfoldingandsubsequentprecipitationduringheattreatmentofUNSS32750SDSSsheetsamples.ThemicrostructuralandtexturalchangeshavebeenfollowedusingSEM/EBSDtechniques.Uponfolding,bothatextureandstraingradientforminthefolded/bentregion,subsequentheattreatmentat845℃resultsintheferritephasetotransformtosigma,austeniteandchiphases.Transformationwasfoundtobeacceleratedbystrain.Completetransformationoftheferritephaseoccurredwithinhalftheannealingtimerequiredintheunstrainedregions.Thelocalmis-orientationsintheferriteandaustenitephasesreducedduringannealing,however,thereductionintheaustenitewasnotveryhighandasignificantamountremainedevenafterthelongestannealingtime.Thetexturecomponentsthatdevelopedduringthefoldingprocessremainedunchangedevenafteronehourannealingat845℃.TheimplicationofthesefindingscouldhaveabearingontheformationofsigmaphaseduringweldingofSDSSthatmayhaveresidualstressesintroducedduringfinalprocessing.

简介：Coarsening,embrittlementandcorrosionsensitizationinahightemperatureheat-affectedzone(HTHAZ)arethemajorproblemswhen12%chromiumlowcarbonstainlesssteelisbeingwelded,whichinducethedeteriorationoftheimpacttoughnessatalowtemperatureandintergranularcorrosionresistanceproperty.ThisstudyinvestigatesthecorrespondingmicrostructuresinHTHAZwithdifferentchemicalcompositionsandheatinputsthroughthermalsimulationtests.Theresultsshowthatthemartensitecontentincreaseswiththedescendingofferritefactor(FF)whenFFisbelow9.0andheatinputinfluencesthemicrostructureofhighFFsteelinHTHAZ.Martensiteof12%CrstainlesssteelinHTHAZwithonlyNbstabilizationreticularlydistributesatferritegrainboundaries.

简介：ThisstudyinvestigatedthevolatilizationkineticsofleadinpelletsmadeofZn-Pb-bearingdustsmixedwithcoalpowder,inanitrogenatmosphereandinthetemperaturerangebetween1100℃-1300℃,andshowedthatthereductiontemperaturehasasignificanteffectonthevolatilizationrateofleadandthatneithertheparticlesizeofthecoalpowdernortheextracarboncontenthasanyeffectonthevolatilizationrate.Theobtainedactivationenergyforthevolatilizationofleadis88.74kJ/mol.Thevolatilizationrateofleadiscontrolledbyboththeleadevaporationreactionandthediffusionofgaseousleadthroughthegasboundarylayercoveringthesurfaceofthereducedliquidlead.

简介：Thestudyintroducesthechemicalcomposition,mechanicalproperties,physicalpropertiesandproductionprocessesoftheFe-23Mn-2Al-Vausteniticsteel.Investigationsweremadeintotheformationofcracksinthehot-rolledFe-23Mn-2Al-Vsteelplates,withopticalmicroscopy(OM),scanningelectronmicroscopy(SEM)andenergydispersivespectrum(EDS).Theresultshaveshownthatintergranularoxidationinthereheatingfurnaceisthemaincauseofthecracksonthesurfaceofthehot-rolledsteelplates.Thesurfacecrackingcanbelargelyavoidedbycontrollingtheremainingoxygencontentinthereheatingfurnaceandimprovingcontinuouscasting(CC)processestoincreasethethicknessoffineequiaxedgrainlayerofthesteelslabs.

简介：Advancedhighstrengthsteel(AHSS)hasbeenwidelyusedintheautomobileindustry.TheresistancespotweldingperformanceofDP980andQ&P980steelswasstudiedthroughcomparingthetwosteels'weldingcurrentrange,tensileshearstrength(TSS),crosstensionstrength(CTS),weldspots'microhardness,etc.Thefollowingconclusionswereachieved:ItiseasyforbothDP980andQ&P980steelstogetanuggetsizebiggerthan4mm,theyallhaveweldingcurrentrangesexceeding2kAandhighweldstrength.