采用高速摄像机、电流电压采集仪及光谱分析仪分别研究低功率YAG激光-熔化极气体弧焊(GMAW)复合焊接过程中的电弧形态、电压特点及局部电子温度、密度变化。在此基础上,运用等离子体热力学平衡理论分析复合焊接电弧等离子体的行为特征。试验表明,低功率YAG激光吸引、压缩GMAW电弧,提高电弧局部区域的电子温度至(15400±900) K,电子密度至(1.265±0.101)×1017cm-3,降低了GMAW热源输出电压,促进了焊接电弧等离子体局部热力学平衡(LTE)的建立。

Behavior of welding arc plasma,characteristic of welding voltage,local changes of electron temperature and electron density were investigated respectively with high speed camera,inductance gauge of current and voltage,spectrometer in low power YAG laser-gas metal arc welding (GMAW) hybrid welding process comparing with simple GMAW welding case. Based on the experimental results,behaviors of hybrid welding arc plasma were explained by plasma theory of thermodynamic equilibrium. The results indicated that,due to the input of YAG laser,the GMAW arc was attracted and constricted,electron temperature and electron density of local arc were increased to (15400±900) K and (1.265±0.101)×1017cm-3,the voltage output of GMAW source was decreased,and the formation of local thermodynamic equilibrium (LTE) of hybrid welding arc plasma was accelerated.