焊接电流对镁合金/不锈钢电阻点焊接头的影响  

Effect of Welding Current on Resistance Spot Welding Joint of Magnesium Alloy and Stainless Steel

作　　者：徐杰[1] 王田 XU Jie;WANG Tian(College of Intelligent Manufacturingg and Automobile,Chongqing Technology & Business Institute,Chongqing 401520, China)

机构地区：[1]重庆工商职业学院智能制造与汽车学院,重庆401520

出　　处：《热加工工艺》2019年第1期214-216,共3页Hot Working Technology

基　　金：重庆市教委科学技术研究项目(KJ1737461)

摘　　要：以Zn箔作为中间层对镁合金和不锈钢进行电阻点焊连接,通过扫描电镜、能谱分析仪、拉伸试验机等研究了焊接电流对接头微观组织、熔核尺寸和拉剪力的影响,并分析了接头缺陷形式。结果表明,当热输入不恰当时,镁/钢接头中有孔洞和裂纹产生。在镁/钢接头界面区域有Fe_2Al_5反应层生成,在接头镁合金侧有MgZn_2相生成。反应层的厚度和熔核直径随点焊电流的增大而增大。此外,镁/钢接头拉剪力随焊接电流增加先增大后减小,当采用焊接电流10k A时,接头拉剪力具有最大值4100 N。Taking Zn foil as the interlayer, the magnesium alloy and stainless steel were welded by resistance spot welding. The effects of welding current on the microstructure, nugget size and tensile-shear force were investigated with the aid of SEM, EDS, tensile testing machine. The results show that holes and cracks occur when the heat input is improper.Fe2Al5 reaction layer forms in the interface of Mg/steel joint and MgZn2 phases form at the Mg alloy side. The thickness of reaction layer and nugget size increase with the increase of welding current. Besides, with the welding current increasing, the tensile-shear force of joint increases firstly and then decreases. The tensile shear force reaches maximum value of 4100 N when the welding current is 10 kA.

关 键 词：镁合金 不锈钢 电阻点焊 拉剪力 熔核尺寸 

分 类 号：TG453.9[金属学及工艺—焊接]