In this paper, fiber laser-arc hybrid welding plasma was studied by using the multiple-imaging method. Four images of plasma with different light intensity areas can be simultaneously observed in a picture. The arc plasma and metal plasma can be distinguished in the high light intensity area, and the arc plasma has an approximate average light intensity distribution. The metal plasma is mainly concentrated above the keyhole, and its temperature/electron density first increases and then decreases along the laser beam direction. The light intensity of plasma is approximately proportional to its temperature in the low light intensity area, and its morphology is similar to its temperature field profile obtained by numerical simulation. By using the multiple-imaging method, the high light intensity area morphology of plasma can be measured, and the simulation results of the plasma temperature field in the low light intensity area can be verified.

中文翻译：

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光纤激光-电弧复合焊接过程中诱导等离子体不同光强区域的表征

本文采用多重成像方法对光纤激光-电弧复合焊接等离子体进行了研究。在一张图片中可以同时观察到四个具有不同光强区域的等离子体图像。在高光强区可以区分电弧等离子体和金属等离子体，电弧等离子体具有近似平均的光强分布。金属等离子体主要集中在小孔上方，其温度/电子密度沿激光束方向先增大后减小。在低光强区域，等离子体的光强与其温度近似成正比，其形貌与数值模拟得到的温度场剖面相似。通过使用多重成像方法，可以测量等离子体的高光强区域形貌，