A7N01铝合金激光-MIG复合焊电参数特性分析

针对A7N01铝合金激光-MIG复合焊接过程,研究不同保护气氛下电参数的变化规律,以及保护气成分对熔滴过渡周期的影响规律。采用不同占比的氦-氩混合保护气对A7N01铝合金进行了焊接过程的电参数采集以及熔滴过渡周期统计;研究不同成分的氦-氩混合保护气对焊缝成形及气孔缺陷的影响。结果表明,当混合气氛中的氩气所占比例较高时,电参数规律性较强、较为稳定;氦气所占比例大于50%的情况下,伴随着短路电压的出现,焊接过程电参数不再具有周期性。氦气所占比例越高,熔滴过渡周期越长;当氦气的比例超过50%后,焊缝成形质量下降,出现焊瘤及飞溅现象;氦气的加入会改善高纯氩保护氛围下不可避免的气孔现象,降低气孔率及气孔尺寸。

Study on electrical parameters of laser-MIG hybrid welding of A7N01 aluminum alloy

For the laser-MIG hybrid welding process of A7N01 aluminium alloy,the change rules of electrical parameters under different protective atmosphere and the influence of protective gas composition on metal transfer period are studied. In the experiment, different proportions of helium-argon mixed shielded gas are used to collect the electrical parameters of A7N01 aluminum alloy during welding process and to calculate the metal transfer period. The effects of different proportions of helium-argon mixed shielded gases on weld formation and pore defects are studied. The results show that the regularity of electrical parameters is strong and stable when the proportion of argon in mixed atmosphere is high;with the appearance of short circuit voltage,the electrical parameters of welding process are no longer periodic when the proportion of helium is more than 50%. The higher the proportion of helium,the longer the metal transfer period;when the proportion of helium exceeds 50%,the quality of weld formation decreases,and overlap and spatters occur;the addition of helium will improve the inevitable blowhole phenomenon in high purity argon atmosphere and reduce the porosity and blowhole size.