为了研究激光入射角变化对车身用镀锌板的焊接性能的影响, 首先采用正交试验, 通过对焊接件外观形貌分析和进行拉剪试验, 得出了激光垂直入射时较理想的焊接参量, 然后在该理想参量下进行了不同入射角度下的镀锌板焊接试验, 分析了入射角改变对焊接件外观形貌、焊缝截面、焊缝板间连接宽度以及所承受的拉剪载荷的影响。结果表明, 激光入射角小于30°时焊缝外观形貌良好, 能承受较大的拉剪载荷且拉剪试验均断裂在母材区; 焊缝板间连接宽度对抗拉剪载荷有重要影响; 板间间隙微小变化对临界入射角值有较大的影响。

In order to study effect of laser incident angles on welding performance of galvanized sheet, firstly orthogonal test was adopted to obtain ideal welding parameters at normal incidence through analyzing the weld topography, tension and shear load. Then galvanized sheet welding tests at different incident angles were carried out under the same ideal parameters at vertical incidence.The transverse weld topography, the connect width between plates and tension and shear load were analyzed when the incident angle changed. The research results show that fine weld topography and greater tension and shear load can be obtained at incident angle less than 30°;the connect width between plates has an significant influence on tension and shear load; slight change of the gap between plates will bring large effect on the critical incident angle.