中文摘要：

超射流过渡工艺是对常规脉冲MIG焊接工艺的改进，以期减少气孔率、增大熔深。本文采用高速摄像同步分析系统分析了焊接过程熔滴过渡和电流电压波形特点。结果发现，与常规脉冲MIG焊接相比，超射流过渡工艺熔滴过渡模式由“一脉一滴”变为“一脉多滴”，脉冲周期明显变长，达到33ms，占空比明显增加；当改变参数时，峰值电流变大，基值电流仍为35A。峰值阶段电流较大，持续时间长，大的电弧力造成熔池表面下凹，熔池底部加热作用明显，熔深增大。峰值阶段电流持续变化，电弧力的改变使熔池产生振荡，熔池中气体容易逸出，减少气孔。

英文摘要：

Spray MODAL welding process is an improvement of conventional pulse MIG welding process in order to reduce the rate of gas pore and obtain deeper penetration. The characteristics of droplet transfer and waveforms of weld current and voltage were analyzed by high speed camera synchronous system. The results show that, compared with normal pulse MIG welding, droplet transfer mode of spray MODAL technology changes from ＂one pulse one drop＂ to ＂one pulse more drops ＂, and the pulse period significantly increases to 33 ms. Duty cycle increases significantly. When the parameters are changed the peak current is larger, but the base current is still 35 A. Current of peak stage is large and the duration is longer. Large arc force causes a concave weld pool surface,which has a more efficiency heating effect on the pool bottom,and the penetration increases.The change of current of peak stage leads to the change of arc force, which makes the molten pool produces oscillation, so the gas of pool can escape and the gas pore reduces.