简介：CO2气体保护焊具有效率高、成本低、应用范围广等优点,且随着CO2焊接设备、焊接材料和焊接工艺的研究发展,使CO2气体保护焊在矿用汽车工业中获得广泛应用。

简介：Laserblankweldingisbecomingmoreandmoreimportantintheautomotiveindustryandthequalityoftheweldiscriticalforasuccessfulapplication.Afullyautomatedsolutionisrequiredtoinspectthequalityoftheblanks.ThispaperpresentsavisioninspectionsystemwithaCMOScamerawhichusesART2networktoinspectthedefectson-linetoobtainthegeometryandthequalityoftheweldseam.TheneuralnetworkART2hasthecapabilityofself-learningfromtheenvironment.Itcandistinguishthedefectsthathavebeenlearnedbeforeandgivenewoutputsfornewdefects.SoART2networkissuitableforweldqualityinspectioninlaserblankwelding.Additionally,aCO_2laserisusedfortheblankbutt-welding.

简介：“搅拌摩擦焊技术”被誉为21世纪最具革命性的焊接技术，历经二十多年的技术研发和工程化推广，已经在国内外各丁业领域得到了广泛应用。在其基础上发展起来的双轴肩搅拌摩擦焊技术，针对薄壁结构、中空结构及其他复杂结构．有着更为显著的技术优势，为搅拌摩擦焊技术注入了新的活力。在陔技术的基础上，

简介：大型薄壁不锈钢容器的焊接若采用开坡口单面氩弧焊,不仅焊接变形较大,且需专门的背气保护;若采用手工电弧焊,背面还需清根,不仅变形较大,还费时费力。不开坡口的双枪氩弧焊技术不仅能够减小焊接变形,提高生产效率,且容易上手。该技术焊接效率高、质量稳定,因此在生产中得到广泛应用。

简介：本试验利用CMT-TWIN双丝焊接技术,在Q235基体上堆焊Φ1.2ER5356和Φ1.2ER50S-6,以获得致密、无裂纹孔洞等缺陷的Fe-Al堆焊层。堆焊层主要由柱状晶组成,内部析出了细小的弥散相,EDS表明堆焊层存在Fe3Al。硬度测试表明：熔合区硬度分布不均匀,硬度峰值达450HV,而焊缝中心区硬度大致在350-400HV之间,表明此区域可能含Fe3Al较多。

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简介：Bead-on-plateCO2laserweldingof1000MPagradetransformationinducedplasticity(TRIP)steelwasconductedunderdifferentweldingpowers,weldingspeedsandshieldgases.Themacrostructuralandmicrostructuralfeaturesoftheweldedjointwereinvestigated.Theincreaseofweldingspeedreducedthewidthoftheweldbeadandtheporositiesintheweldbeadresultingfromthedifferentflowmodeofmeltedmetalinweldpool.ThedecreaseofweldingpoweroruseofshieldgasofheliumalsocontributedtothereductionofporosityinBead-on-plateCO2laserweldingof1000MPagradetransformationinducedplasticity(TRIP)steelwasconductedunderdifferentweldingpowers,weldingspeedsandshieldgases.Themacrostructuralandmicrostructuralfeaturesoftheweldedjointwereinvestigated.Theincreaseofweldingspeedreducedthewidthoftheweldbeadandtheporositiesintheweldbeadresultingfromthedifferentflowmodeofmeltedmetalinweldpool.Thedecreaseofweldingpoweroruseofshieldgasofheliumalsocontributedtothereductionofporosityintheweldbeadduetothealleviationofinducedplasmaformation,thusstabilizingthekeyhole.TheporosityformationintimatelycorrelatedwiththeevaporationofalloyelementMninthebasemetal.Thelaserweldedmetalhadsamemartensitemicrostructureasthatofwater-quenchedbasemetal.Theweldingparameterswhichincreasedcoolingrateallledtofinemicrostructuresoftheweldbead.

简介：本文采用有限元分析方法,建立了双丝埋弧焊温度场的有限元计算模型,利用ABAQUS软件的FORTRAN语言编写程序,实现在移动热源载荷下的有限元计算,得到不同时刻的双丝埋弧焊温度场分布,并且通过实验验证,与仿真结果比较吻合。

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简介：Duetothedisturbancesofspatters,dustsandstrongarclight,itisdifficulttodetectthemoltenpooledgeandtheweldlinelocationinCO2weldingprocesses.Themedianfilteringandself-multiplicationwasemployedtopreprocesstheimageoftheCO2weldinginordertodetecteffectivelytheedgeofmoltenpoolandthelocationofweldline.TheB-splinewaveletalgorithmhasbeeninvestigated,theinfluenceofdifferentscalesandthresholdsontheresultsoftheedgedetectionhavebeencomparedandanalyzed.TheexperimentalresultsshowthatbetterperformancetoextracttheedgeofthemoltenpoolandthelocationofweldlinecanbeobtainedbyusingtheB-splinewavelettransform.Theproposededgedetectionapproachcanbefurtherappliedtothecontrolofmoltendepthandtheseamtracking.

简介：Theobjectiveofthisstudyistoinvestigatetheinfluenceofaddingtinyamountofmixedrareearth(La,Ce)andSrtoAl-20Cu-5Si-2Nifillermetal,byanalyzingthemicrostructure,wettabilityandmechanicalpropertiesofbrazedjoints.Theresultsshowthawiththeadditionofmixedrareearth(La,Ce)intoAl-20Cu-5Si-2Nialloy,theα-AlsolidsolutionaswellasCuAl_2(Ni)intermetalliccompoundphasesignificantlyreduced,whilemoreAl-SieutecticphaseandAl-Si-Cuternaryeutecticphasewereproduced.Andasmixedrareearth(La,Ce)addedin,thewettabilityofAl-20Cu-5Si-2Nifillermetaldecreased,whiletheshearstrengthofthebrazedjointsincreased.TheadditionofMinorSrmodificatedAl-20Cu-5Si-2Nifillermetal,furtherreducedtheCuAl_2(Ni)intermetalliccompoundphase,whichwaspartiallyreplacedAl-Si-Cuternaryeutecticphase.Asaresult,thetensilestrengthaswellasthewettabilityofthefillermetalwasimproved.

简介：LaserweldingwithfillerwireofAZ31magnesiumalloysisinvestigatedusingaCO2laserexperimentalsystem.Theeffectofthreedifferentfillerwiresonthejointpropertiesisresearched.Theresultsshowthattheweldappearancecanbeeffectivelyimprovedwhenusinglaserweldingwithfillerwire.ThemicrohardnessandtensilestrengthofjointsarealmostthesameasthoseofthebasemetalwhenERAZ31orERAZ61wireisadopted.However,whenthefillerwireofER5356aluminumalloyisused,themechanicalpropertiesofjointsbecomeworse.ForERAZ31andERAZ61fillerwires,themicrostructureofweldzoneshowssmalldendritegrains.Incomparison,forER5356fillerwire,theweldshowsastructureofsnowydendritesandmanyintermetalliccompoundsandeutecticphasesdistributeinthedendrites.Theseintermetallicconstituentswithlowmeltingpointincreasethetendencyofhotcrackandresultinfragilejointproperties.Therefore,ERAZ31andERAZ61wirearemoresuitablefillermaterialthanER5356forCO2laserweldingofAZ31magnesiumalloys.

简介：ThedistributionsoftheaxialstressandshearstressinAl2O3-TiC/Q235diffusionbondedjointswerestudiedusingfiniteelementmethod(FEM).Theeffectofinterlayerthicknessontheaxialstressandshearstresswasalsoinvestigated.Theresultsindicatethatthegradientsoftheaxialstressandshearstressaregreatnearthejointedge.ThemaximalshearstressproducesattheinterfaceoftheAl2O3-TiCandTiinterlayer.WiththeincreaseofCuinterlayerthickness,themagnitudesoftheaxialstressandshearstressfirstdecreaseandthenincrease.Thedistributionoftheaxialstresschangesgreatlywithalittlechangeintheshearstress.TheshearfractureinitiatesattheinterfaceoftheAl2O3-TiC/TiinterlayerwithhighshearstressandthenpropagatestotheAl2O3-TiCside,whichisconsistentwiththestressFEMcalculatingresults.

简介：ＣｏｍｐａｒｉｓｏｎｏｆｍｅｃｈａｎｉｃａｌｐｒｏｐｅｒｔｉｅｓｉｎｗｅｌｄｅｄｊｏｉｎｔｆｏｒＣＯ２ａｒｃｗｅｌｄｉｎｇｂｙｕｓｉｎｇｔｈｅｍｉｃｒｏ－ｓｈｅａｒｔｅｓｔａｎｄｉｍｐａｃｔｔｅｓｔ￥ＺｈｏｕＬｉｘｉａ；ＷａｎｇＳｈｉｙｕａｎａｎｄ?..

简介：Thispaperintroducedthebasictheoryandalgorithmofthesurrogatedatamethod,whichproposedarigorouswaytodetecttherandomandseeminglystochasticcharacteristicsinasystem.TheGaussiandataandtheRosslerdatawereusedtoshowtheavailabilityandeffectivityofthismethod.Accordingtotheanalysisbythismethodbasedontheshort-circuitingcurrentsignalsundertheconditionsofthesamevoltageanddifferentwirefeedspeeds,itisdemonstratedthattheelectricalsignalstimeseriesexhibitapparentlyrandomnesswhentheweldingparametersdonotmatch.However,theelectricalsignalstimeseriesaredeterministicwhenamatchisfound.Thestabilityofshort-circuitingtransferprocesscouldbejudgedexactlybythemethodofsurrogatedata.

简介：ThesusceptibilityofweldedjointfortheX65pipelinesteeltoH2Sstresscorrosioncracking(SCC)isinvestigated.SCCtestsonthesteelarecarriedoutintheenvironmentbasedonNACETM-01-77solutionwithsaturatedgaseousH2S.Thethresholdstressintensityfactorandcrackpropagationvelocityarecalculatedaccordingtowedge-openingloading(WOL)specimens.Thethree-dimensionalelastic-plasticfiniteelementanalysisofWOLspecimensisperformedbyusingtheFEMprogrammingpackageANSYS.Stressfieldandconcentrationofhydrogendistributionpropertyaheadofthecracktipareobtained.ThispapersurveyedthemicrostructureofweldedjointandstudiedonthemechanicalpropertiesofX65pipelinesteel.Itprovidesexperimentalbasisforstudyingstresscorrosion.Theresultsofnumericalanalysisareconsistentwithconclusionsofstresscorrosiontest.

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