激光透射焊接过程产生的热集中现象会导致焊件接头处产生不利于结构刚度和承载能力的残余应力, 为有效减少焊接残余应力提高焊接强度, 本文对聚碳酸酯PC/铜/PC进行焊接实验。利用小孔法测量焊接件焊缝中心位置的残余应力, 通过建立响应曲面实验研究焊接功率、焊接速度、铜膜的宽度对焊接强度和残余应力以及焊缝形貌的影响, 计算得到拟合方程并对工艺参数进行优化并获得了最佳工艺参数。实验结果表明, 激光功率和焊接速度对焊接残余应力有显著影响, 铜膜的宽度对残余应力的影响较小。

The heat concentration caused by laser transmission welding will cause residual stress at the welded joint which is not conducive to structural rigidity and load bearing capacity. In order to effectively reduce the welding residual stress and improve the welding strength, this paper conducts welding experiments on polycarbonate PC/Cu/PC. The hole drilling method is used to measure the residual stresses in the seam center. The experiment is established by response surface methodology (RSM). The effects of welding power, welding speed and width of copper film on welding strength, residual stress and weld morphology were studied. The fitting equation is obtained by calculation and the process parameters are optimized. The experimental results show that the laser power and welding speed have a significant effect on the welding residual stress, and the influence of the width of the copper film is little.