学科分类
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37 个结果
  • 简介:Duetothedisturbancesofspatters,dustsandstrongarclight,itisdifficulttodetectthemoltenpooledgeandtheweldlinelocationinCO2weldingprocesses.Themedianfilteringandself-multiplicationwasemployedtopreprocesstheimageoftheCO2weldinginordertodetecteffectivelytheedgeofmoltenpoolandthelocationofweldline.TheB-splinewaveletalgorithmhasbeeninvestigated,theinfluenceofdifferentscalesandthresholdsontheresultsoftheedgedetectionhavebeencomparedandanalyzed.TheexperimentalresultsshowthatbetterperformancetoextracttheedgeofthemoltenpoolandthelocationofweldlinecanbeobtainedbyusingtheB-splinewavelettransform.Theproposededgedetectionapproachcanbefurtherappliedtothecontrolofmoltendepthandtheseamtracking.

  • 标签: 二氧化碳焊接 熔池 B-齿槽小波 边缘检测
  • 简介:Widegapbrazing(WGB)experimentsusingthebuttedspecimenwitha1.5mmgapwerecarriedoutfortherepairofthefailedK418Bsuperalloylow-pressureturbinevanes.Thehightemperaturecreeprupturestrengthsofthebrazedjointsweretested,andthemicrostructuresandfracturesurfacesofthejointswereobserved.TheresultsshowthatthemicrostructureofK418Balloyjointiscomposedofdenseequiaxedgrain,smallanddiscretecompoundswithafewmicro-pores.Duringthecreeprupturetest,thecracksinitiatepreferentiallyatthemicro-poreorthegrainboundary,thenpropagatealongthegrainboundarytillthefracturehappens.Thecreeprupturestrengthat700℃ofthebrazedjointswith50%brazemetalintheworkingpartcouldexceed90%thatoftheK418Bsuperalloy,andthejointswith100%brazemetalintheworkingpartachieve70%to80%ofthecreeprupturestrengthsfortheK418Bbasemetal.

  • 标签: 钎焊接头 组织性能 合金 蠕变断裂强度 大间隙钎焊 差距
  • 简介:ThermalbehaviorofB4Cparticlesunderplasmaarcpowdersurfacingcondition¥WANGXibao;ZHANGWenyue;LUTongliandPENGJie(HebeiUniversity...

  • 标签: B4C plasma ARC POWDER SURFACING thermal
  • 简介:BondingofAl2O3tocuisperformeddirectlyusingTifoilattemperatureof1273K.Themicrostructureofthejointinterfaceisinuestigatedthroughscanningelectronmicroscope(SEM),electron.probemicroanalysis(EPMA)andX-raydiffraction(XRD).theeffectoftheinitialtifoilthicknessonthereactionlayerthicknessandthejointStrengthareinvestigated.

  • 标签: ALUMINA active BRAZING INTERFACIAL reaction joint
  • 简介:本文结合生产实践,简要分析提出了CO2气体保护焊目前所存在的缺陷与问题,并提出了相应的解决方法与CO2气体保护焊的发展趋势。

  • 标签: CO2气体保护焊 缺陷 趋势
  • 简介:AvisiontrackingsystemofrobotCOshorttransferweldingWuRenyu;WangGuodongandLiXiaoqi(TianjinUniversity)ZhangLianchang(MotorolaC?..

  • 标签: ROBOT WELDING real-time control image processing
  • 简介:本文介绍了CO2气体保护电弧焊的冶金特点,CO2气体保护电弧焊焊接过程中的熔滴过渡形式;从焊丝的冶金过程,焊接时的工艺参数的选择及调整等方面探讨了汽车白车身CO2焊接质量的控制。

  • 标签: 汽车白车身 CO2焊接 质量
  • 简介:IntheautomaticCO2arcwelding,thealterationoftheverticaldistancebetweentheweldingtorchandtheworkpiecehasastrongeffectontheweldingparameterssuchasweldingcurrentandvoltage,withtheresultthattheappearanceandqualityofweldarenotsteady.Toweakentheinfluenceofthedistancealteration,amethodisputforwardinthepaper.Themethodisthatthealternatewire-feedcontrolisusedforcompensatingtheweldingcurrent.Onthebasisoftheoreticalanalysis,astaticnumericalmodelforalternatewire-feedcontrolisestablished.Theexperimentsshowthatthemodel-basedregulationofthewirefeedratecancompensatetheweldingcurrentandensuretheappearanceofweld.Whenthealterationofverticaldistancebetweenthetorchandtheworkpieceisgreater,notonlyisthewirefeedrateregulated,buttheoutputvoltageofthepowersourceisadjustedtoensuretheappearanceandqualityofweld.

  • 标签: 二氧化碳电弧焊 金属丝延伸 进料效率 力学平衡
  • 简介:本文介绍了CO2焊工艺方法及其高效、优质、低成本的综合优越性以及在石油、化工、天然气工程建设中的应用与发展,不同种类的气体与焊丝相组合的工艺特点及控制焊缝成形的操作技术。

  • 标签: CO2焊 综合机械性能 应用
  • 简介:ThispaperintroducesabrazingprocessbetweenAl_2O_3ceramicandInvaralloy.Al_2O_3canbebrazedwithInvareffectively.TheinterfacialstructureofAl_2O_3/Invarjointcanbeexpressedas:Invar/Ag(s,s)+Cu(s,s)+Fe_2Ti(zoneⅠ)/Ag(s,s)+Cu(s,s)+Fe_2Ti+NiTi+Cu_3Ti(zoneⅡ)/Ag(s,s)+Cu(s,s)+Cu_2Ti+Al(s,s)+TiC+TiO(zoneⅢ)/Al_2O_3.Themaximumshearstrengthof139MPawasmeasuredforas-brazedAl_2O_3/Invarjointbrazedat850℃for25minor900℃for15min.

  • 标签: AL2O3陶瓷 钎焊接头 界面结构 力学性能 因瓦合金 剪切强度
  • 简介:针对某企业支架制造过程中采用二氧化碳气体保护焊,焊接接头出现大量未熔合缺陷,分析了未熔合产生的原因,并阐述了防止未熔合的措施。实践证明该措施有效地控制了未熔合缺陷,提高了焊缝合格率,获得了满意的焊缝质量,具有推广应用价值。同时,是否将“未熔合”焊接缺陷与“气孔和飞溅”相提并论,都是CO2焊时容易出现的缺陷,以引起同仁的重视。

  • 标签: 二氧化碳气体保护焊 未熔合 工艺措施
  • 简介:AnewkindofsimpleandflexibleCO_2weldingsystemwasdevelopedtocarryoutwaveformcontrol.ThesystemconsistedofIGBTinverter,PWMcircuitandmicroprocessorunit(MPU),inwhichtheoutputcurrentofconstantcurrent(CC)powersupplycouldbechangedaccordingtotransientphysicalstate,andthevariabledownsloperatecontrolcouldbeusedtoensureastableweldingprocess.Theweldingexperimentresultsprovedtheeffectivenessofthiscontrolapproach.

  • 标签: 二氧化碳保护焊 波形控制 微处理器 短路变换
  • 简介:Theeffectsoftwopost-weldheattreatmentprocessesonthemicrostructureandfatiguepropertiesoftheelectronbeamweldedjointsof30CrMnSiNi2Asteelwerestudied.Electronbeamlocalpost-weldheattreatment(EBLPWHT),inavacuumchamber,immediatelyafterweldingandatraditionalfurnacewholepost-weldheattreatment(FWPWHT)wereaccepted.Theexperimentalresultsshowthat,afterEBLPWHT,themainmicrostructureofweldischangedfromcoarseacicularmartensiteintolathmartensite,andbasemetalischangedfromferriteandperliteintoupperbainiteandresidualaustenite,howeverthemicrostructuresofdifferentzonesofjointsinFWPWHTconditionsaretemperedsorbite.Thefatiguecrackgrowthrateda/dNofweldsandbasemetalarenotobviouslychangedamongEBLPWHT,FWPWHTtestandas-welded(AW)test,asthemechanicalpropertiesofmaterialshaveacertainbutnotlargeeffectontheda/dNofweldedjoints.TheresistancetonearthresholdfatiguecrackgrowthdataofweldedjointscanbelargelyimprovedbyEBLPWHTanditisrelatedtomicrostructureandcrackclosureeffect.

  • 标签: 微观结构 疲劳裂缝 电子束焊接 合金钢 局部加热处理