摘要
采用冷金属过渡(Cold Metal Transfer,CMT)熔钎焊方法对6061铝合金和Q235镀锌钢进行对接焊接,采用金相显微镜、显微硬度计对焊接接头微观组织和硬度进行观察.结果表明:CMT技术可获得成形良好的铝/钢接头.随着焊接速度的降低,焊缝宽度增大;焊缝区为等轴晶和树枝晶组织,熔合区为柱状晶组织.硬度测试表明:接头的维氏硬度(HV)比母材低,过渡区硬度最高,为180,焊缝硬度较低,约为80,钢侧热影响区硬度为152,熔化区存在一定的软化.拉伸试验表明:试样在拉伸过程中发生明显的塑性变形,接头抗拉强度为134 MPa,为铝合金母材的72%.
Cold metal transfer（CMT）welding brazing method was used for butt weld of 6061 aluminum alloy and Q235 galvanized steel.Then,the microstructures and microhardness of welded joint were observed by optical microscope and microhardness tester.The results show that CMT technology can got well-formed welded joint;the weld width increases with the decrease of welding speed,the crystallizing morphology on the weld seam are equiaxed grains and dendrites and that on the fusion zone are columnar crystals.The microhardness test shows that the Vickers hardness of the joint is lower than that of base metal,the maximum hardness of the transition zone is 180;hardness of the weld is lower,about 80;average hardness of the affected zone of steel side is 152,softening occurs in the melting zone.Tensile test result shows that obvious plastic deformation occured during the process.The tensile strength of welded joint is 134 MPa,which is 72% of the base aluminum alloy.
出处
《上海工程技术大学学报》
CAS
2017年第4期289-294,共6页
Journal of Shanghai University of Engineering Science
基金
上海市汽车工业科技发展基金资助项目(1404)
上海工程技术大学研究生科研创新计划资助项目(16KY0510)
关键词
冷金属过渡
异种金属
微观组织
力学性能
cold metal transfer（CMT）
dissimilar metal
microstructure
mechanical property
