纯钛/镁合金异种材料电阻点焊接头组织和性能分析

Microstructures and properties of resistance spot welded joint of pure Ti/Mg alloy dissimilar metals

摘要: 采用电阻点焊技术焊接TA2纯钛板和AZ31B镁合金板。研究了不同焊接参数（点焊电流、点焊时间和电极压力）对焊点拉剪强度的影响，分析Ti/Mg焊点界面区域微观组织构成及显微硬度分布。分析结果表明，Ti/Mg焊点拉剪强度随点焊电流、焊接时间和电极压力的增大呈现先增加后降低的趋势。当采用点焊电流10 kA，焊接时间8周波，电极压力4 kN等参数时，Ti/Mg焊点拉剪力达到最大值3.7 kN。能谱分析表明，Mg/Ti界面反应层由Mg₁₇Al₁₂，α-Mg和TiAl₃等相组成，其具有最大显微硬度146 HV。

Abstract: AZ31B magnesium alloy and TA2 pure titanium were welded by resistance spot welding technology. The influences of welding current,time and electrode force on joint strength were studied. Besides,the microstructures and micro hardness of Mg/Ti interfacial zone were investigated. With the increase of welding current,welding time and electrode force,the joint strength increases firstly and then decreases.The maximum joint strength of 3. 7 kN is obtained at welding current of 10 kA,welding time of 8 cycles and electrode force of 4 kN. The microstructures of Mg/Ti interfacial zone are consisted with Mg₁₇Al₁₂,α-Mg and TiAl₃. The maximum micro hardness is 146 HV.