学科分类
/ 1
13 个结果
  • 简介:焊接技术的发展都是以焊接高效率化和高产能化为最大目标。要实现高效率化焊接重要措施之一就是提高焊接速度,一般熔化极气保焊的焊接速度仅为0.3-0.5m/min。当焊接速度较高时(〉0.6m/min)易产生焊道不连续、咬边和产生大量气孔等缺陷,因而研究、推广焊接高效率化的技术成果是我国焊接领域里的重要课题。本文介绍一种在造船行业和钢结构焊接领域里常见型钢简捷、高效化平角焊接方法。即用双丝-熔池简捷高效快速焊接(焊接速度为1.2-1.5m/min,焊脚高度5mm)时也能达到良好的焊接规范和焊接性能的高效化平角焊接方法。经过多年的在造船行业和钢结构焊接中的T型钢焊接生产中证明,采用双丝-熔池气体保护焊可提高T型钢生产效率和焊接质量,减少焊接变形,因而双丝-熔池气体保护焊得到快速发展和广泛的应用。

  • 标签: 快速 高效率 简捷实用 易于推广
  • 简介:Three-dimensionalfiniteelementmodelwasestablishedtosimulatetemperaturefieldsofT-jointtitaniumsheetsduringTIGweldingwithfiniteelementmethod(FEM)software.Temperaturedependentmaterialpropertiesandtheeffectoflatentheatwereconsidered.Atechniqueofelementbirthanddeathwasusedtosimulatetheprocessofweldedmetalfilling.DynamicvariationprocessoftemperaturefieldsduringTIGweldingwasachieved.Thesimulatedresultsagreedwellwiththemeasuredresults.

  • 标签: 钛合金 TIG焊接 温度场 有限元法 数字模拟
  • 简介:Inthisstudy,atwo-stepheatingprocessisintroducedfortransientliquidphase(TLP)diffusionbondingforsoundjointswithT91heatresistantsteels.Atfirst,ashort-timehighertemperatureheatingstepisaddressedtomelttheinterlayer,followedbythesecondsteptocompleteisothermalsolidificationatalowtemperature.Themostcriticalfeatureofournewmethodisproducinganon-planarinterfaceattheT91heatresistantsteelsjoint.WeproposeatransitionalliquidphasebondingofT91heatresistantsteelsbythisapproach.Sincejointmicrostructureshavebeenstudied,wetestedthetensilestrengthtoassessjointmechanicalproperty.Theresultindicatesthatthesolidifiedbondmaycontainaprimarysolid-solution,similarcompositiontotheparentmetalandfreefromprecipitates.Jointtensilestrengthofthejointisnotlowerthanparentmaterials.Jointbend'sstrengthsareenhancedduetothehighermetal-to-metaljunctionproducinganon-planarbondlines.Nevertheless,thetraditionaltransientliquidphasediffusionbondingproducesplanarones.Bondingparametersofnewprocessare1260℃for0.5minand1230℃for4min.

  • 标签: 液相扩散焊 T91钢 工艺 焊接接头 瞬时 等温凝固
  • 简介:Themicrostructureandmechanicalpropertiesoffrictionstirwelded2.5mm7050-77451aluminumalloynaturalaging72hand17520hwereinvestigated,respectively.Theuniaxialtensiletestshowedthatyieldstrength,tensilestrengthandelongationofthejoints17520hnaturalagingwereabout20%,12%and24%higherthanthosejointsnaturalaging72h.Hardnessprofileofnaturalaging17520hjointwitnessedsignificantenhancementinnuggetzone,comparedwith72hnaturalaging.Differentialscanningcalorimetry(DSC)andtransmissionelectronmicroscopy(TEM)testrevealedthatmoreGuinier-Prestonzone,η'andηphaseemergedinnuggetzoneasnaturalagingdurationincreased,highdensityofdislocationlocatedwithingrainboundaryinnuggetzoneofjointsnaturalaging72h.ItisconcludedthatnaturalagingwasfeasibletoenhancestrengthandplasticityofFSWjointssimultaneously.

  • 标签:
  • 简介:中国检验认证集团是经国务院批准成立,国家质量监督检验检疫总局认可、国家认证认可监督委员会资质认证,中国合格评定认可委员会认可,以“检验、鉴定、认证、测试”为主业的中国最大的检验认证国有机构。目前公司的主要服务内容包括:质量保证和质量控制质量保证和质量控制检验可以用来检验材料、零部件和最终产品的质量。

  • 标签: 国家质量监督检验检疫总局 认证机构 中国 监造 工程 陕西
  • 简介:Inthispaper,6mmthick2219-T6aluminumalloywasjoinedbymeansofvariablepolaritytungsten-arcwelding(VP-TIG)andtheinfluenceofgradientmismatchesonVP-TIGjointsisinvestigated.Theaveragetensilestrengthofthejointsreduces32%,53%and59%,whenthemismatchofthejointwas0.635mm,1.44mm,1.83mm,respectively.Incompletepenetration,additionalbendingmoment(Ma)anddecreaseofeffectiveloadregionareaareconsideredtoexplainthisphenomenon.Thefracturelocationoftensilespecimensoccurredattheweldzone(WZ)closetopartialmeltzone(PMZ),correspondingtoasharpdeclineofmicrohardnessfromPMZtoWZ.Theoriginalpositionoffractureisfoundatweldtoe,whereincompletepenetrationformsduetotheintroductionofgradientmismatches.

  • 标签: 2219-T6 aluminum alloy VP-TIG GRADIENT MISMATCHES
  • 简介:国家电网公司工程的统一安排中,通过大量实践、理论技术论证,将钢管塔作为该特高压工程的首选塔型,详细提出了有关特高压同塔双回钢管塔焊接技术要求。本文主要讲述了在特高压工程当中针对直缝焊管与带颈法兰等焊缝的质量检测常用方法,如爬坡检测、横波检测等。

  • 标签: 钢管塔 焊缝质量 直缝焊管 爬坡检测 横波检测
  • 简介:为了对高合金异种钢焊接工艺有更多的了解,本文通过对某火力电厂锅炉后屏过热器检修换管过程中涉及到的钢种(SA213-T91马氏体高合金耐热钢与Cr25Ni13奥氏体高合金耐热钢)的现场焊接工艺进行介绍,以给类似工程的施工提供一定的借鉴。

  • 标签: SA213-T91钢 Cr25Ni13钢 焊接工艺 异种钢焊接 活动夹块
  • 简介:Stationaryshoulderfrictionstirlapwelding(SSFSLW)wassuccessfullyusedtoweld6005A-T6aluminumalloyinthispaper.EffectofpinrotatingspeedoncrosssectionmorphologiesandlapshearstrengthoftheSSFSLWjointsweremainlydiscussed.Resultsshowthatjointswithoutflashandshouldermarkscanbeobtainedbythestationaryshoulder.CrosssectionoftheSSFSLWjointpresentsabasin-likemorphologyandlittlematerialloss.Byincreasingtherotatingspeedfrom1000rpmto1600rpm,botheffectivesheetthicknessandlapwidthincrease,whilelapshearfailureloadfirstlydecreasesandthenincreases.Themaximumfailureloadof14.05kNisattainedwhen1000rpmisused.AllSSFSLWjointspresentshearfracturemode.

  • 标签: 搅拌摩擦焊 铝合金焊接 旋转速度 剪切强度 搭接 抗剪强度