通过采用和不采用填充合金粉末的比较试验,研究了填充合金粉末对铝合金高功率CO2激光焊接功率阈值、焊缝成形和焊接过程稳定性的影响。实验表明,合金粉末的加入可以提高焊接过程中激光能量的有效利用率;激光深熔焊接时的临界功率密度明显降低,合金粉末还可以减弱等离子体在高度方向上的膨胀跳动,使等离子体在工件表面能维持跳动幅度的相对稳定,有利于获得较为稳定的焊接过程和理想的焊缝成形,并通过试验,获得了焊缝饱满,有一定余高和鱼鳞纹光滑的焊缝。

The influences of the filler metal powder on the intensity threshold, weld formation and process stability have been studied during high power CO2 laser welding of aluminum alloy through the comparison between welding with and without metal powder. The experiment results demonstrate that the addition of the metal powder enhances the energy coupling efficiency during laser welding and reduces the power density threshold which has been validated by the testing data of Laserscope UFF 100.The power density threshold of A2219 can be reduce to about 50%. Meanwhile, the pictures collected by the high speed camera indicate that the addition of the metal powder weakens the fluctuation of the laser-induced plasma and keeps the plasma stabilizing above the workpiece. So a stable welding process and well-formed weld can be obtained in a relatively easy way.