Rectangular Wave AC TIG Arc Welding of Aluminum Alloy

Study on Rectangular Wave AC Arc Welding (Rept.1)

Abstract

Rectangular wave AC TIG arc welding phenomena were investigated with respect to the welding current waveform, using an experimental AC power source of the transistor controlled inverter type, which was designed and set up. Current level and duration of each polarity in a cycle were separately varied from 0 to 300 amp. in the frequency range up to 500 Hz. It is shown that the current level and the duration of EN polarity in a cycle are dominant parameters in the current waveform for the arc pressure and the bead formation, but those of EP polarity are responsible for the cleaning action in AC TIG welding of Al alloy.