脉冲MIG焊熔滴过渡中值波形的控制策略

针对脉冲MIG焊熔滴过渡过程的控制，提出中值波形控制策略的新工艺方法，详细阐述了中值电流及中值时间对焊接过程熔滴过渡的影响规律。采用中中值波形控制方法对钢进行焊接试验，确定了最佳的中值电流和中值时间。试验结果表明，中值电流较小时出现瞬时短路，中值电流较大时失去了中值阶段的作用，中值电流为一理想值时焊接效果较好。在确定了中值电流给定为理想值的基础上，得到了中值时间为一理想值时焊接效果较好，中值时间较小时不会过渡熔滴，而中值时间较大时会在中值阶段过渡多个熔滴的结果。

Control strategy of waveform with median phase in droplet transfer for pulsed MIG welding

For the droplet transfer for pulsed metal inert-gas(MIG) welding, a new waveform control method of waveform with median phase was presented. The effect of median current and median time on the droplet transfer was studied. The optimum median current and median time were found by experiment when welding steel using waveform with middle median phase. The experiment result shows that instantaneous short circuit occurs when the median current is small and the median phase has not effect on the droplet transfer when the median current is large, and when the median current is an optimum value, the welding effect is satisfactory. On the basis of defining the median current as an optimum value, the welding effect is satisfactory when the median time is an optimum value. There is not droplet transfer when the median time is small and there is multitude droplets transfer when the median time is large.