YAG脉冲激光焊接的光致等离子体机理研究

Study on Mechanism of Laser-induced Plasma during YAG-pulse Laser Welding

针对 YAG脉冲激光焊接 Al及 4 5#钢时产生的光致等离子体 ,采用空心圆电极探测等离子体电信号 ;建立探测器内等离子体区域分析的理论模型 ,并用试验加以验证。研究结果表明 ,在负电压段 ,等离子体电信号的电流随电压增加呈现饱和趋势 ;理论与试验曲线比较证明 ,等离子体温度高于被焊材料气化温度约 30 0 K。

A hollow cylindrical electrode was employed to detect the electrical signal of laser induced plasma during YAG pulse laser welding of Al and 45 # steel. The theoeritical model has been established for analysis of the plasma region and compared with the experiments.The research results show that the current exhibit a saturation effect in the I V curves of plasma signal with increasing voltage in the negative voltage region, and the plasma temperature is higher than the vaporzation temperature of welded materials.