基于可视化观察,研究了光纤激光-TIG电弧复合焊接等离子体的多重形貌特征。结果表明:基于等离子体光强的非均匀分布特性,利用多重成像法可同时观测出复合焊接等离子体的三重像和四重像,并可区分出金属等离子体和电弧等离子体,而且采用氦气保护比采用氩气保护更易于区分;在相同的电弧电流和成像条件下,复合焊接等离子体的面积明显大于单电弧焊接等离子体的面积;TIG电弧-激光复合焊接等离子体的面积明显大于激光-TIG电弧复合焊接等离子体的面积;复合焊接等离子体中金属等离子体与保护气并未充分混合,金属等离子体对复合焊接等离子体的形貌、稳定性等方面具有重要影响。

In this study, various morphological features of plasma were studied by using the visual observation during fiber laser-TIG arc hybrid welding. The results show that based on the non-uniform distribution of light intensity of plasma, approximately 3-4 images of plasma can be obtained simultaneously by using the multi-imaging method and the metal and arc plasma can be distinguished. Compared with the Ar shielding gas, the metal and arc plasma can be distinguished more easily under the He atmosphere. Under the same arc current and imaging conditions, the area of the hybrid welding plasma is obviously larger than that of the single arc plasma, and the area of the plasma in hybrid welding with an TIG arc-laser mode is obviously larger than that of the plasma in hybrid welding with a laser-TIG arc mode. Further analysis shows that the metal vapor and shielding gas are not fully mixed during the hybrid welding. In addition, metal plasma significantly affect the morphology and stability of the hybrid-welding plasma.