高强铝铜合金MIG焊工艺  

MIG welding process of high strength Al-Cu alloy

作　　者：杨成刚[1] 陈玉华[1] 邢丽[1] 国旭明[2] 

机构地区：[1]南昌航空大学材料科学与工程学院,江西南昌330063 [2]沈阳航空工业学院,沈阳110136

出　　处：《焊接学报》2008年第7期13-16,共4页Transactions of The China Welding Institution

基　　金：国家高技术研究发展计划(863计划)项目(2002AA305402)

摘　　要：研究了单脉冲、电磁搅拌、电磁搅拌和单脉冲复合作用对高强Al-Cu合金MIG焊焊缝组织及性能的影响。结果表明,普通MIG焊焊缝组织几乎由粗大、方向性很强的柱状晶组成,接头抗拉强度仅为286.5 MPa,断后伸长率为2.4%;单脉冲或电磁搅拌均能细化焊缝组织,提高接头力学性能;电磁搅拌和单脉冲复合作用降低了固-液界面前沿液相的温度梯度,增加了非均质形核率,促使柱状晶转变为细小均匀的等轴晶,细化了焊缝组织,显著提高了接头力学性能,接头抗拉强度高达326.0 MPa,断后伸长率为7.8%。The effects of the single pulse,the electromagnetic stirring and the electromagnetic stirring plus single pulse hybrid on the microstructures and properties of high strength Al-Cu alloy welds were investigated.The results show that the structures of weld with conventional MIG welding are coarse,oriented columnar grains;the ultimate tensile strength of welded joint is 286.5 MPa,ductibility is 2.4%;both the single pulse and the electromagnetic stirring can improve the mechanical properties by refining the microstructure;the electromagnetical stirring plus single pulse hybrid decreases the thermal gradient at the solid-liquid interface in the weld pool,enhances the density of heterogeneous nucleation,results in the coarse and oriented columnar grains reforming to fine equiaxed grains,and significantly improves the mechanical properties of weld joint,which the ultimate tensile strength is 326.0 MPa and the ductibility is 7.8%.

关 键 词：高强Al—Cu合金 电磁搅拌 焊缝组织 

分 类 号：TG146.2[一般工业技术—材料科学与工程]