Wettability, microstructure and properties of 6061 aluminum alloy/304 stainless steel butt joint achieved by laser-metal inert-gas hybrid welding-brazing  

6061铝合金/304不锈钢激光-金属惰性气体复合熔钎焊对接接头润湿性、显微组织及性能（英文）

作　　者：Jun-yu XUE Yuan-xing LI Hui CHEN Zong-tao ZHU 薛珺予;李远星;陈辉;朱宗涛(西南交通大学材料先进技术教育部重点实验室,成都610031)

机构地区：[1]Key Laboratory of Advanced Technologies of Materials,Ministry of Education,Southwest Jiaotong University,Chengdu 610031,China

出　　处：《Transactions of Nonferrous Metals Society of China》2018年第10期1938-1946,共9页中国有色金属学报（英文版）

基　　金：Project(51405398) supported by the National Natural Science Foundation of China

摘　　要：Laser-metal inert-gas(MIG)hybrid welding-brazing was applied to the butt joint of 6061-T6 aluminum alloy and 304 stainless steel.The microstructure and mechanical properties of the joint were studied.An excellent joint-section shape was achieved from good wettability on both sides of the stainless steel.Scanning electron microscopy,energy-dispersive spectroscopy and X-ray diffractometry indicated an intermetallic compound(IMC)layer at the 6061-T6/304 interface.The IMC thickness was controlled to be^2μm,which was attributed to the advantage of the laser-MIG hybrid method.Fe3Al dominated in the IMC layer at the interface between the stainless steel and the back reinforcement.The IMC layer in the remaining regions consisted mainly of Fe4Al13.A thinner IMC layer and better wettability on both sides of the stainless steel were obtained,because of the optimized energy distribution from a combination of a laser beam with a MIG arc.The average tensile strength of the joint with reinforcement using laser-MIG hybrid process was improved to be 174 MPa(60%of the 6061-T6 tensile strength),which was significantly higher than that of the joint by traditional MIG process.采用激光-金属惰性气体(MIG)复合熔钎焊的方法实现6061-T6铝合金与304不锈钢异种金属对接接头的焊接,并研究焊后接头的显微组织和力学性能。由于熔融金属在不锈钢两侧润湿铺展良好,焊后接头具有良好的截面形貌。采用扫描电镜、能谱仪及X射线衍射仪表征6061-T6/304界面的金属间化合物(IMC)层。结果表明,基于激光-MIG复合焊的优势,IMC层的整体厚度被控制在2μm左右,位于不锈钢和接头背部余高之间的IMC层的组织主要为Fe3Al,位于其他位置的IMC层的组织主要为Fe_4Al_(13)。由于激光束与MIG电弧热源的结合能够有效优化热源分布,焊后接头的IMC层厚度较薄,同时,熔融金属在不锈钢两侧具有良好的润湿铺展。焊后带有余高的接头的抗拉强度可达174 MPa,约为6061母材强度的60%,明显高于传统单一MIG热源作用下的接头的抗拉强度。

关 键 词：WELDING-BRAZING laser-metal inert-gas hybrid welding butt joint microstructure 

分 类 号：TG457.1[金属学及工艺—焊接]