Abstract: 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.

Key words: short circuiting transfer;weld bead geometry;current waveform