基于搅拌摩擦焊技术的镁/钛异种合金连接  

Joining of Mg/Ti Dissimilar Alloys Based on Friction Stir Welding

作　　者：李世海 张风东 刘雪松[2] LI Shihai;ZHANG Fengdong;LIU Xuesong(CRRC Qingdao Sifang Co.,Ltd.,Qingdao 266111,China;State Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology,Harbin 150001,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]哈尔滨工业大学先进焊接与连接国家重点实验室,黑龙江哈尔滨150001

出　　处：《热加工工艺》2021年第3期134-136,共3页Hot Working Technology

基　　金：国家自然科学基金项目(51075102)。

摘　　要：采用搅拌摩擦焊技术对2 mm厚Ti6Al4V钛合金和AZ31B镁合金进行连接,研究不同转速下接头的成形、界面组织和拉伸强度。结果表明,转速过低会导致Mg/Ti异种合金接头内部形成孔洞缺陷。靠近Mg/Ti界面的钛合金中出现Al元素富集现象,随着转速的升高,Al元素的富集程度提升。Mg/Ti界面是接头的薄弱区,在拉伸载荷下,接头沿Mg/Ti界面断裂。接头拉伸强度随着转速的提升而增大,当转速为900 r/min时,强度达到168 MPa。Ti6 Al4 V titanium alloy and AZ31 B magnesium alloy with the thickness of 2 mm were welded by friction stir welding. The joint formation, interface microstructure and tensile strength under different rotating speeds were investigated.The results show that low rotating speed induces the appearance of void defect inside the joint of Mg/Ti dissimilar alloys. The enrichment of Al element appears in the Ti alloy near the Mg/Ti interface and the enrichment degree increases with the increase of rotating speed. The Mg/Ti interface is the weak region of the joint and the fracture occurs along the Mg/Ti interface under tensile load. The tensile strength of joint increases with the increase of rotating speed and its value reaches 168 MPa when the rotating speed is 900 r/min.

关 键 词：搅拌摩擦焊 Mg/Ti异种合金 转速 显微组织 拉伸强度 

分 类 号：TG453.9[金属学及工艺—焊接]