激光-电弧复合焊等离子体特性与焊缝熔深相关性研究

利用光谱仪、高速相机对激光-电弧两脉冲复合焊接过程的等离子体辐射光谱及电弧形态进行了采集。基于Boltzmann作图法和Stark展宽法计算了等离子体电子温度和电子密度，研究了不同激光脉冲作用时间和不同频率脉冲电弧对电子温度和电子密度的影响。结合等离子体发射光谱图和高速图像信息，分析了激光-电弧两脉冲复合焊等离子体物理特性。结果表明：随着激光脉冲作用时间的增加，电弧收缩，亮度提高，电子温度降低，电子密度升高，熔深值增大，光谱强度增加，焊缝中氮含量降低；随着电弧脉冲频率的增加，电弧体积变大，亮度提高，电子温度和电子密度均下降，熔深值呈现逐渐降低的趋势，焊缝区上部的电弧焊特征明显增强。

Study on Correlation between Plasma Property and Weld Penetration in Laser-arc Hybrid Welding

The plasma radiation spectrum and the shape of arc are collected by using the spectrometer and the high speed camera in the process of two-pulse laser-arc hybrid welding.The plasma electron temperature and electron density are calculated based on Boltzmann plotting method and Stark broadening method,and the electron temperature and electron density at different pulse durations and different frequencies of pulse arc are investigated.Based on the spectral analysis and the high speed image,the plasma physical properties of laser-arc two-pulse hybrid welding are studied.The results show that the arc shrinks and the brightness increases with the increase in laser pulse duration,the electron temperature decreases and the electron density increases with the increase in laser pulse duration,the penetration depth increases,the intensity of spectrum increases and the nitrogen content in the weld decreases;the arc volume becomes larger than before,the brightness increases with the increase in pulse arc frequency,the electron temperature decreases,the electron density decreases,the penetration depth decreases,and the characteristics of the arc welding at the upper part of the weld zone are obviously enhanced.