采用IPG YLS-6000光纤激光进行平板焊接实验。利用高速摄像观测羽辉的形态，通过超音速横向气帘在不同高度处抑制羽辉的高度，并测量熔宽和熔深，研究羽辉对焊接过程的影响。结果表明高功率光纤激光焊接羽辉可分为两部分：小孔口波动部分和类似于激光束聚焦形态的狭长形部分。当超音速横向气帘在距焊接板面5 mm高度处抑制羽辉上升后，焊接熔深和熔宽分别提高约20%和缩小约24%；焊接过程的稳定性和焊缝表面成形也得到了很大提高。进一步分析表明，羽辉对光纤焊接过程产生了显著影响，其本质是羽辉中存在的微粒对光纤激光产生了显著影响。

The plate welding experiment is carried out by IPG YLS-600 fiber laser. The effect of plume is observed by a high speed camera, and measuring the weld width and penetration as the plume height is controlled by using the supersonic cross jet at different heights during bead-on-plate welding. The results show that the plume can be divided into two parts: a randomly fluctuating plume out of the keyhole and a slender plume similar to the focused laser beam. The weld penetration and width have an improvement of about 20% and a decrease of about 24%, respectively, as the rising of plume is controlled by applying a cross jet at 5 mm height during welding. And the stability of the welding process and the appearances of the weld seam are also greatly improved. Further analysis indicates that the effect nature of plume on the fiber laser is the effect of particles in plume on the fiber laser, which results in a significant effect on the welding process.