简介：UsingXenonlamplightstoovercomethestronginterferencefromtheweldingarc,acomputer-basedsystemisdevelopedtosenseandvisualizethemetaltransferinGMAW.Thissystemcombinesthrough-the-arcsensingoftheweldingcurrentandarcvoltagewithhighspeedimagingofthemetaltransfer.Itcansimultaneouslydisplaythemetaltransferprocessesandwaveformsofelectricalweldingparametersinreal-timeThemetaltransfervideosandwaveformsofelectricalweldingparameterscanberecorded.Metaltransfersundervariousweldingconditionshavebeeninvestigatedwiththesystemdeveloped.

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简介：ElectrodeENiFe-Cland￡"4303wereselectedtojointhecementedcarbideWC-2QCoandcarbonsteel45byshieldedmetalarcweldingprocess.Microstructureandbendingpropertyofthecorrespondingjointswereanalyzed.Theresultsshowedthatthecarbonsteelelectrode￡"4303hadnopropermetallurgyconditionforthearcweldingofcementedcarbideandcarbonsteel.TheCandNicontentofthecastironelectrodeENiFe-Clcouldmeettheconditionofpreventingtheformationof7]carbide,whichwassuittothearcweldingofcementedcarbideandcarbonsteel,buttheoperationparametersneededtobeoptimizedtominimizetheslaginclusion.ThealloyWC-2QCowhichdidnotfitforcoldarcwelding,byadoptingthemeasureofbeingpreheatedat723K/or1hbeforewelding,andbeingkeptat723Kfor3hafterweldingthenfollowedfurnacecoolingcouldavoidthehappeningofcrackintheWC-20C〇basemetal.

简介：Theinfraredcameraisusedtoinvestigatethetemperaturefieldofgasmetalarcwelding.Theresultsshowthatthetemperaturedistributionofweldpoolandadjacentareaappearsconeshape.AnewheatsourcemodelcombinedbyGaussiandistributionheatsourceofthearcandconicaldistributionheatsourceofthedropletissetupbasedontheexperimentalresults,andwiththecombinedboundaryconditions,thetemperaturefieldofgasmetalarcweldingissimulatedusingfiniteelementmethod.AccordingtothecomparisonbetweentheresultsofexperimentandsimulationintemperaturefieldshowsthatthenewcombinedheatsourcemodelismoreaccurateandeffectivethantheGaussheatsourcemodel.

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简介：Onthebasisoftheexperimentalworkofadhesion(W)data,theadhesionbetweentransitionmetalcar-bidesandpureliquidmetalswhichdonotreactwithcarbidesisstudied.Inviewofgreatscatteringoftheex-perimentalvaluesofW,acriticalanalysisoftheseresultsisperformed.TheselectedWvaluesfor9copper/carbidesystemsand6metal/TiCsystemsareusedtodiscussthevarioussuggestionsconcerningthemechanismofadhesionandtoevidencetheroleofthevalenceelectronsofthebothcarbideandmetalontheinteractionsbetweenmetalsandcarbides.Theinteractionsbetweenametalandacarbideareessentiallymetal-licinteractions,resultingfromtheoverlappingofthevalenceelectronsatthemetal/carbideinterface.

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简介：Metaltransferisanimportantphenomenoninmetalinertgas(MIG)arcweldingwithlongitudinalalternatingmagneticfield.Itisofgreatsignificancetoobservethemetaltransfermodesunderdifferentexcitatorycurrentsandfrequencies.However,itisverydifficulttoviewthemetaltransferprocessdirectlyduringwelding,duetothestronginterferencefromthearclight.Toobtaintherelationshipbetweenthemetaltransfermodesandthedifferentmagneticfields,ahigh-speedvideocamerawasusedtoacquiretheimagesofglobules.Differentmetaltransfermodesundertheconditionsofdifferentmagneticfieldsandweldingparameterswerestudied.Theexperimentshowsclearimagesofdroplettransferaswellasinfluenceoflongitudinalmagneticfieldonbothmetaltransferandglobuleshape.

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简介：MechanicalpropertiesofSMAW(shieldedmetalarcwelding)weldmetal(yieldstrengthhigherthan900MPa)withsystematicadditionsofcopper(upto1.48wt%)weretested.Themicrostructureandprecipitatesindifferentregionswereanalyzedbyopticalmicroscopeandtransmissionelectronmicroscope.Theresultsindicatethatcopperimprovesthelowtemperaturetoughnessofweldmetalwhenthecoppercontentislowandreachesthepeakvalue48J(at-50℃)with0.2wt%copperadditions.Whenthecontentishighthecopperprecipitatesasε-Cuphaseinthereheatzoneofmiddlebeads.Theseprecipitatesimprovethestrengthoftheweldmetalevidently(yieldstrengthupto975MPa)withoutobviouseffectonthelowtemperaturetoughness.Thecopperwithin1.1wt%contentcanimprovethestrengthwithouttoughnessloss.

简介：Accordingtothespecificationofsuperalloy-stainlesssteelarcbrazingandcharacteristicofthebasemetal,abestfillermetalwhichhasrelativelowermeltingpoint,nicewettability,goodweldforming,andadequateshearstrengthwasresearched.TheexperimentresultsshowthatwettabilityofCuFeMnonthestainlesssteelisverypoor,concomitantwithamassofpurplesootduringtheweldingwhichdeterioratestheworkingcondition.CuSiMnhasthebestwettabilityonboththesuperalloyandstainlesssteel,butthereremainsalotofpitandslagonthesurfaceoftheweldbead.Copper-basedsolderhasthehighestmeltingpointanditswettabilityandclearancefillabilityareweakerthanCuSi3.WettabilityandclearancefillabilityoftheCuSi3arethebestinallthecandidatefillermetals,anditsweldissmoothnessandhashighershearstrength.Foritscomprehensiveability,CuSi3isselectedasthefinalfillermetal.

简介：Recoveryprocessesofsecondaryresourcesusuallyencounterproblemsbecauseofthediversecompositionsofwastes.Toenhancetheapplicabilityoftraditionalhydrometallurgicalprocesstowardsecondaryresources,theadjustmentofcomponentsisnecessary.Intraditionalhydrometallurgicalseparation,precipitationandcomplexationareextensivelyused.However,theircombinationasaspecificmetalseparationmethodhasnotyetbeenstudiedindetail.Thisapproachisverypromisingforsolvingproblemscausedbychangeablecomponentsduringrecyclingprocessesofsecondaryresources.Thispaperreviewstheeffectsofprecipitationandcomplexationinmetalseparationprocesses,andametalseparationmethodsystemof‘‘complexation–precipitation’’developedtoadjustthecomponentsofsecondaryresourcesisintroduced.

简介：OnthebasisOftheYoung-LaplaceEquationthatdescribesthepressuredifferencebetweeneachsideofacurvedliquidsurface,astaticequilibriummodelisestablishedtodescribethesurfaceshapeoftheweldbead.Thegeo-metricalmodelforthemoltenpoolisincluded,whichisessentialtoexplaintheundercutphenomenonduringhighspeedbead-on-platewelding.Theresultsgotfromaniterationalgorithmshowthatitistheforcebalanceontheliquidmixtureofthedepositedmetalandthedepositedmetalandthemoltenbasemetalandthemoltenbasemetalthatcausestheundercut.Somefactorsandtheireffectsarealsoana-lyzed.

简介：金属涂的cenospheres广泛地在工业被使用了。不同涂层方法导致不同典型金属电影。由化学涂层的cenosphere上的金属电影不看起来很光滑，展出积累的金属和表面上的大头针洞并且离开某点uncoated。同时，金属电影紧没被吸收到cenospheres上并且是容易的开脱皮。然而，磁控管劈啪作响准备的金属电影是紧缩的，光滑并且在大头针洞外面。这部电影有好亲密关系到cenosphere表面。甚至当cenosphere被压碎时，如此的电影不用它分开。两个都，金属电影给一样的XRD模式，显示金属的水晶结构由这二个方法拍摄是一样。化学涂层是一个复杂过程并且有害环境，而是它适合极其细小的粉末涂层(粒子尺寸能是不到2)。磁控管劈啪作响的方法是环境的友好并且快速工作，但是这个方法要求特殊设计的设备并且不为极其细小的粉末工作。如果粒子尺寸是不到30，涂层过程是难的继续。

简介：Nb-bearingslagfromBaotouhotmetalwaschlorinatedinthesolidstatewithmoltenCaCl2undervacuum,96～98%MnOorFeObeingthusvolatilized.Byreducingthechloridizedresidueunderadditionofflux,ferroniobiumwithabout60%Nbwassuccessfullymade.KineticstudyofchlorinationofsyntheticMnO-Nb2O5-SiO2andFeO-Nb2O5-SiO2slagsystemswasconducted,andanon-reactingcoremodelforthedemanganificationwithfreeuseofactivitywasformulatedandtherate-controllingstepwasexplained.

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