保护气体对激光+双丝MAG复合焊焊缝形貌和电弧特性的影响

Effects of shielding gas on weld shape and arc characteristic in laser+twin-electrode MAG hybrid welding

在激光+单电弧复合焊工艺的基础上,通过再添加一个电弧的方式,形成激光+双丝脉冲MAG复合焊工艺。研究了保护气体为φ(Ar)80%+φ(CO2)20%(情况A)和φ(Ar)40%+φ(CO2)10%+φ(He)50%(情况B)时对激光+双丝MAG复合焊焊缝表面成形和电弧特性的影响。利用LabVIEW信号采集系统和高速摄像系统同步采集焊接电流、电弧电压波形和电弧形态。结果表明,在焊缝表面和焊道两侧边缘处,肉眼可见斑点状、不连续的氧化物,情况A与情况B相比,情况A氧化物含量高,熔宽小;而情况B焊道平整,鱼鳞纹清晰。情况A中由于CO2含量较高,使其对电弧的冷却作用增强,减弱了激光对电弧的稳定作用,断弧次数比情况B多。

Based on laser＋single arc welding, the laser＋twin-electrode MAG hybrid welding is developed by adding the other arc.With the shielding gas of φ （Ar）80%＋φ（CO2）20%（condition A） and φ（Ar）40%＋φ（He）50%＋φ（CO2）10%（condition B）, the effects of the varying ratio of CO2 on weld shape and arc characteristic are studied in laser＋twin-electrode MAG hybrid welding.The LabVIEW signal acquisition system and high-speed photography system a~ used to monitor welding current,arc voltage and arc behavior.The results show that spotted and discontinuous oxides are visible on the surface and both sides of the weld.Compared condition A with condition B,the oxides content under condition A is high and the weld width is small.Then under condition B,the weld is smooth and scaly figure is distinct.Due to the high CO2 ratio in condition A,the effect of cooling arcs is enhanced and the effect of stabilizing arcs is weakened.The arc interruption times under condition A is more than under condition B.