机械制造文摘焊接分册激光一电弧复合焊专题Q1400超高强钢激光－MAG复合焊与MAG组织及性能对比牟梓豪，滕彬，徐（中国机械总院集团哈尔滨焊接研究所有限公司，黑龙江哈尔滨150028）摘要：针对一种屈服强度1400MPa新型超高强钢，对比分析了在使用低强匹配焊材的条件下MAG和激光-MAG复合焊的组织及性能差异。2种焊接工艺的成形及截面形貌均连续均匀，无气孔、裂纹、夹渣等微观缺陷。MAG采用2mm钝边的60°坡口，热输入大、冷却速度较慢，焊缝组织主要为马氏体+贝氏体组织，焊缝－40℃冲击吸收能量为45J,为母材的150%；热影响区冲击吸收能量为30J，与母材水平相当；接头抗拉强度为1166MPa，相当于母材的69%。激光-MAG复合焊采用6mm钝边的40°坡口，打底焊焊缝为马氏体组织；填充焊焊缝为马氏体+贝氏体组织；焊缝-40℃冲击吸收能量与MAG相当，但热影响区的冲击吸收能量达到42J，优于MAG和母材；接头抗拉强度接近1300MPa,高于MAG125MPa，相当于母材的76%。激光-MAG复合焊焊接效率优于MAG,达到MAG的3倍以上。关键词：激光-MAG复合焊；MAG；超高强钢；显微组织；力学性能中图分类号：TG456.7Comparisonofmicrostructureandmechanicalpropertiesbetweenlaser-archybridweldingandMAGforultrahighstrengthsteelMuZihao,TengBin,XuKai(HarbinWeldingInstituteLimitedCompany,Harbin150028,Heilongjiang,China)Abstract:Microstructureandmechanicalpropertiesofanewultrahighstrengthsteelwithyieldstrengthof1400MPawerecomparedbetweenMAGandlaser-MAGhybridweldingundertheconditionoflowstrengthmatchingweldingmaterial.Formationandcross-sectionmorphologyofthetwoprocesseswerecontinuousanduniform,andtherewerenomicrodefectssuchaspores,cracksandslaginclusions.60°groovewith2mmbluntedgewasadoptedinMAG,whichhadlargeheatinputandslowcoolingspeed.Microstructureofweldwasmainlymartensiteandbainite.Impactabsorbedenergyofweldat-40Cwas45J,whichwas150%ofbasemetal.Heataffectedzonewas30J,whichwasequivalenttobasemetal.Tensilestrengthofweldedjointswas1166MPa,whichwasequivalentto69%ofbasemetal.40°groovewith6mmbluntedgewasadoptedinlaser-MAGhybridwelding,backingweldwasmartensite,andfillingweldwasmartensiteandbain-ite.Impactabsorbedenergyofweldat-40Cwasequivalenttobasemetal,whileimpactabsorbedenergyofheataffecte...
