激光深熔焊的光致等离子体行为模拟研究

Simulation of Photoinduced Plasma Behavior in Laser Penetration Welding

对6063铝合金的激光深熔焊过程中光致等离子行为进行了研究。运用多通道分析装置获取六条由激光诱导等离子体形成的Mg I谱线,使用高速摄像装置捕获等离子体图像;将数据和图像传送到智能终端中,采用Fluent软件分析激光深熔焊接过程中的光致等离子体各阶段的状态。结果表明,激光功率密度随着小孔深度的增加而增大。在激光焊接的起始阶段,光致等离子体的温度变化较大,随着时间推移进入稳定阶段,等离子体的温度趋于恒定。随着焊接的继续,光致等离子体的不恒定性主要体现为光致等离子体的位置上下波动和尺度变化。

The photoinduced plasma behavior during laser penetration welding of 6063 aluminum alloy was investigated. Six Mg I lines formed by laser induced plasma were obtained by using multi-channel analyzer, and plasma images were captured by using high-speed imaging device. The data and images were transmitted to an intelligent terminal, and the states of each stage ofphotoinduced plasma in laser penetration welding were analyzed by using Fluent software. The results show that the laser power density increases with the increase of small hole depth. At the initial stage of laser welding, the temperature of the photoinduced plasma changes greatly, and as the time passes, the plasma temperature tends to be constant. As the welding continues, the instability of the photoinduced plasma is mainly reflected by position fluctuation and scale change of the photoinduced plasma.