激光与电弧间距对激光复合焊熔滴过渡的影响

采用高速摄影设备研究了在两种焊接电流工艺参数下激光与电弧的间距变化对CO2激光-MIG电弧复合焊接熔滴过渡过程的影响.试验发现,在高速MIG焊接时熔滴过渡不稳定,在激光-MIG复合焊接时,由于激光光致等离子体对熔滴的热辐射作用和对电弧的吸引作用而改变了电弧的形态及相应的熔滴的受力状态,使得熔滴的过渡过程发生了改变,对于不同的焊接电流工艺参数,存在不同的最佳激光与电弧间距.结果表明,在最佳间距下,即两个等离子体的耦合作用良好时,熔滴过渡形式为单一的稳定射流过渡,电流电压恒定,焊缝成形良好.

Influence of distance between laser and MIG arc on drop transfer process of CO2 laser-MIG hybrid welding

Influence of different distance between laser and MIG arc on drop transfer process of CO_2 laser-MIG hybrid welding at two kinds of welding currents is studied by using highspeed photography equipment.The experimental results show that drop transfer form produced by single MIG welding at high welding speed is an unstable transfer process.In contrast,during the laser-MIG hybrid welding process,thermal radiation effects of plasma caused by laser on metal drop and attraction force of laser plasma on arc plasma,which results in the variation of arc shape and corresponding forces on metal drop,can have an impertant influence on drop transfer process.There are different optimal distances between the laser and the arc for different welding currents at which beth plasmas can couple well.Under this condition,frequency of drop transfer increases,drop transfer form changes into a single stable spray transfer,welding current and arc voltage remain constant,weld formation is very good,and spatter rate significan reduces.