焊接电流波形对波控短路过渡过程及焊缝形状尺寸的影响

Effect of Welding Current Waveforms on Metal Transfer and Weld Geometry in Controlled Short Circuiting Transfer GMAW

利用电参数与熔滴过渡图像同步检测系统研究波控短路过渡C02焊峰值燃弧电流，Iap、基值燃弧电流Iap以及拖尾时间tw（由峰值燃弧电流切换到基值燃弧电流所用的时间）等电流波形参数对过渡过程和焊缝成形尺寸的影响。结果表明，燃弧时间随着峰值燃弧电流和拖尾时间的增大而增大；短路时间随着峰值燃弧电流的增大而缩短，不随拖尾时间的变化而变化。基值燃弧电流对短路时间和燃弧时间的影响不大。平均燃弧电流随着峰值燃弧电流的增大而减小，随着基值燃弧电流和尾拖时间的增大而增大。随着峰值燃弧电流的增大，熔宽增大，余高减小；而熔深则先减小后增大。基值燃弧电流和拖尾时间的增大均会使熔深和熔宽增大，余高减小。

The effect of waveform parameters of welding current （peak arcing current, basic arcing current and tail-out time, etc.） on metal transfer stability and weld geometry is investigated with a computer-based simultaneously sensing and visualizing system for images of droplet/wire and the transient data of welding current and arc voltage. The results shows that the arcing time increases and the short circuit time decreases with increasing the preset peak arcing current or tail-out time. The background arcing current has little effect on the arcing time and short circuit time. The mean arcing current decreases with increasing the peak arcing current and increases with increasing the background arcing current or tail-out time. With increasing the peak arcing current, the weld width increase, while the reinforcement decrease and the penetration first decreases then increases. An increase in background arcing current or tail-out time causes increases in weld wide and penetration and a decrease in reinforcement.