不同光斑模式的CO2激光在镀锌板钎焊连接中的应用

为了获得CO2激光填丝钎焊镀锌钢板的工艺特性，对CO2激光进行了光束成形，分别研究了圆形光斑、双焦点光斑和矩形光斑3种光斑模式下的镀锌板激光填丝钎焊工艺特点与接头质量．结果表明，采用双焦点的CO2激光光斑加热，钎焊过程适应性增加，并可获得良好的焊缝成形，同时提高激光能量利用率；矩形光斑钎焊可降低镀锌层烧损，但焊接适应性和激光能量利用率降低．通过改变CO2激光的光束能量分布，可以替代Nd：YAG激光进行镀锌板的连接．

CO2 laser brazing galvanized steel sheets with different spot modes

Achieving the process characteristics of CO2 laser brazing galvanized steel sheets is the research purpose in this paper. CO2 laser beam was shaped in three spot modes and the joining process and joint quality were investigated respectively with individual laser spot, dual-focus and rectangular laser spot heating. The experimental results indicate that with the heating of dual-focus laser spot, nice process flexibility, satisfied seam appearance and higher laser energy availability ratio can be achieved. With rectangular laser spot heating, the process can reduce the burning loss of Zn coat, while the adaptability and laser power availability ratio are lower. The research results show that Nd ： YAG laser applied in the brazing of galvanized steel sheets in industry can be replaced with CO2 laser beam whose energy distribution can be changed.