Resistance spot welding method for 800MPa-grade hot-rolled and pickled complex-phase steel plate

The invention relates to the technical field of resistance spot welding, in particular to a resistance spot welding method for an 800MPa-grade hot-rolled and acid-pickled complex-phase steel plate, which adopts the processes of pre-pressing, pre-welding, cooling, welding, heat treatment and post-welding air cooling. The problems that splashing, interface failure, nugget deviation, nugget asymmetry and the like are likely to happen to a hot-rolled and acid-washed multiphase steel plate resistance spot-welded joint can be solved, most of the failure modes of the spot-welded joint are drawing failure, the bearing capacity and the energy absorption capacity of the spot-welded joint are high, and the spot-welded joint is stable in performance and good in quality. 本发明涉及电阻点焊技术领域，特别是涉及一种800MPa级热轧酸洗复相钢板的电阻点焊方法，采用预压、预焊接、冷却、焊接+热处理与焊后空冷工艺，可解决热轧酸洗复相钢板电阻点焊接头易发生飞溅、易发生界面失效、易产生熔核偏移和熔核不对称等问题，点焊接头的失效模式绝大部分为拉拔失效，点焊接头的承载能力和能量吸收能力高，点焊接接头的性能稳定、质量好。