脉冲TCGMAW电流占空比对熔滴过渡和焊缝成形的影响

基于建立的熔滴过渡高速摄像分析系统,对高速脉冲TCGMAW在脉冲电流占空比变化下的熔滴过渡过程进行观察分析,并就脉冲电流占空比变化对熔滴过渡和焊缝成形质量的影响进行了研究。试验结果表明,在所用焊接规范下,当脉冲电流占空比较小时,焊丝熔化速度不能与送丝速度匹配,熔滴过渡方式表现为短路过渡形式,焊缝成形较差,甚至出现断弧、焊不起来的情况;随着脉冲电流占空比的提高,焊丝熔化能量加大,熔滴过渡方式逐渐过渡到射滴过渡和射流过渡,电弧电压的波动范围变小,焊缝成形良好。

Effects of pulse current duty ratio on TCGMAW droplet transfer and weld forming

To investigate the welding mechanism of high-speed pulse twin-wire co-pool gas-shielded metal arc welding(TCGMAW),based on the high-speed camera system,the droplet transfer processes of high speed pulse TCGMAW are observed,under different pulse current duty ratios.The effects of different pulse current duty ratios on the droplet transfer and weld forming are analyzed.Based on the welding specifications described in the paper,the experimental results show:when the duty ratio is lower,the wire melt speed can not match with the wire feed rate.The droplet transfer mode is short circuit transfer and the weld forming are bad with arc breaking and weld fail.Along with the increasing of duty ratio,the melt energy of the wire increase.The droplet transfer modes are projected or spray transfer,and the arc voltages are stable,the weld forming are good.