中文摘要：

针对钢和铝合金三层金属薄板电阻点焊变形问题,采用四因素（焊接时间、焊接电流、焊件厚度和电极压力）三水平（“高”、“中”和“低”）的正交试验,筛选出最优工艺参数组合,并通过拉伸试验机和金相试验检验其焊接质量,通过反变形论证了焊后变形量的正确性。结果表明：焊件厚度对焊接变形的影响最大;正交试验筛选出的最优组合方案不仅有较小的焊接变形量,而且焊后质量达到车身强度要求;反变形法能够有效地减少焊后变形量,且试验后的焊件与未施加反变形的焊件具有一致的焊接质量。

英文摘要：

Considering the resistance spot welding deformation problems of three layers metal sheet combined with steel and aluminum alloys,the orthogonal experiment method,which consists of four factors （welding time,welding current,welding pieces thickness and electrode pressure） and three levels （＂high＂,＂medium＂ and ＂low＂）,was adopted to screen out the optimal process parameters combination. Then tensile testing and metallurgical examination were used to test its post-weld quality and the anti- deformation method was used to prove the correctness of the amount of deformation. The results show that the welding thickness has the greatest impact on the welding deformation. The optimal parameters combination scheme selected by orthogonal experiment not only has a relatively small amount of welding deformation but also its welding quality complies with the requirements of the bus hody strength. The amount of post-weld deformation can be effectively decreased by anti-deformation method. The post-weld quality is consistent with its quality of applying anti-deformation.