点焊工艺参数对汽车用镁铝异种合金接头组织和性能的影响

Effect of spot welding process on microstructure and mechanical property of Mg/Al dissimilar alloy welded joints

采用电阻点焊实现了对镁铝异种金属的焊接,研究了焊接压力、焊接电流、焊接时间对Mg/Al点焊接头组织和力学性能的影响。结果表明,随着焊接压力、焊接电流和焊接时间的增加,Mg/Al异种金属点焊接头拉剪力先增加后减小;熔核晶粒尺寸随着焊接电流的增大、焊接时间的延长而增大;焊接压力7 k N、焊接电流40 k A、焊接时间100 ms时,Mg/Al异种金属点焊接头拉剪力达到最大值3.3 k N。

In this paper,Magnesium and Aluminum were bonded by resistance spot welding.The effect of welding pressure,welding current and welding time on the microstructure and mechanical properties of Mg/Al spot welding joint was studied.The results show that with the increase of the welding pressure,welding current and welding time,the shear force of Mg/Al dissimilar metal welded joint increases firstly and then decreases.The grain in molten nuclear increases with the increasing of welding current or time.At the welding current of 40 kA,welding time of 100 ms,welding pressure of 7 kN,the shear force of Mg/Al dissimilar metal welded joint obtains 3.3 kN.