激光-电弧复合焊接过程中等离子体的耦合行为

激光-电弧复合热源可以形成3种焊缝横截面的形貌,根据焊接参数对焊缝横截面形貌的影响建立了激光和电弧等离子体相互作用的物理机制.通过考察复合焊接过程中电弧等离子体中原子分布状态、电弧辐射光谱信息以及激光"匙孔"的行为对机制进行了验证.结果表明,激光对电弧等离子体的作用是通过激光形成的"匙孔"及其内部等离子体实现的,在适当参数下,电弧等离子体弧柱会进入激光"匙孔"内部,并与"匙孔"等离子体发生耦合放电,最终形成复合等离子体.电弧等离子体和"匙孔"等离子体的耦合作用有利于提高热源的能量密度.

Coupling behavior of plasmas during laser-arc hybrid welding process

Three kinds of welding seam cross-sectional pattern can be found in laser-arc hybrid welding of magnesium alloy. According to the influence of welding parameters on the patterns, the interactive mechanism was proposed. By investigating the atom distributions in the arc plasma, the plasma spectral information and laser keyhole behavior, the mechanism was verified as well. Results show that the effect of laser on arc plasma is realized by both the laser keyhole and the plasma in the keyhole.At certain proper parameters, the arc plasma collumn can extend into the lase keyhole, and discharge with the keyhole plasma. A hybrid plasma can be formed finally. The coupling of arc plasma and keyhole plasma in this style can improve the energy density of the heat source.