超声振动辅助铝/钢激光–MIG熔钎焊外观成形、组织以及拉伸性能研究  

Forming,Microstructure and Tensile Properties of Aluminum/Steel Joint by Ultrasonic Vibration Assisted Laser-MIG Welding-brazing

作　　者：王秋影 邱培现 孙进发 田洪雷 朱宗涛[2] WANG Qiu-ying;QIU Pei-xian;SUN Jin-fa;TIAN Hong-lei;ZHU Zong-tao(CRRC Qingdao Sifang Co.,Ltd.,Shandong Qingdao 266111,China;School of Materials Science and Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]中车青岛四方机车车辆股份有限公司,山东青岛266111 [2]西南交通大学材料科学工程学院,成都610031

出　　处：《精密成形工程》2023年第5期123-130,共8页Journal of Netshape Forming Engineering

基　　金：四川省重点研发计划重大科技专项(2022YFG0086)。

摘　　要：目的利用超声振动改善铝/钢对接接头界面的微观结构,降低气孔缺陷并提高接头力学性能。方法通过超声振动辅助激光–MIG焊接方法实现铝/钢异种金属连接,采用光学显微镜观察焊缝形貌,采用金相显微镜和扫描电子显微镜观察焊缝和界面微观结构,利用拉伸试验机测试接头的拉伸强度。结果超声振动的施加提高了熔融金属的润湿铺展性能,减少了焊缝中的气孔缺陷,并降低了界面层金属间化合物的厚度。带有余高和去除余高的接头拉伸强度由未加超声的175 MPa和154 MPa分别提高到189 MPa和172 MPa。结论利用超声振动的声流、空化效应有效改善了熔融金属的润湿铺展性能和界面微观结构,并在一定程度上消除了气孔缺陷,进而提高了接头的力学性能。The work aims to improve the interface microstructure of aluminum/steel butt joint,reduce the pore defects and enhance the mechanical properties of the joint by ultrasonic vibration.The ultrasonic vibration assisted laser-MIG welding method was used to connect aluminum/steel dissimilar joints.The weld morphology was observed by optical microscopy,the microstructures of weld and interface were observed by metallographic microscope and scanning electron microscope,and the tensile strength of the joint was tested by tensile testing machine.The application of ultrasonic vibration improved the wetting and spreading of molten metal,reduced the pore defects in the weld,and decreased the thickness of intermetallic compounds in the interface layer.The tensile strength of the joint with and without reinforcement increased from 175 MPa and 154 MPa to 189 MPa and 172 MPa,respectively.The acoustic flow and cavitation effect of ultrasonic vibration effectively improve the wettability of molten metal,optimize the microstructure of the interface,and eliminate the porosity defects at a certain extent,so as to enhance the mechanical properties of the joint.

关 键 词：超声振动 铝/钢异种接头 激光-熔化极金属惰性气体保护(MIG)熔钎焊 微观结构 力学性能 

分 类 号：TG456.7[金属学及工艺—焊接]