Bead formation and wire temperature distribution during ULTRA-HIGH-SPEED GTA WELDING using pulse-heated hot-wire

The melting of filler wire is investigated in detail to obtain the precise temperature distribution of the filler wire during ultra-high-speed gas tungsten arc (GTA) welding and develop ultra-high-speed GTA welding with a pulse-heated hot-wire system for three kinds of materials. The melting phenomena of the filler wire were observed using a high-speed camera, and temperature distributions of the filler wire were measured using a radiation thermometer. The results show that ultra-high-speed GTA welding can be achieved with suitable welding conditions for each material. Ultra-high-speed GTA welding requires suitable wire current to obtain a suitable temperature distribution and melting position of the filler wire. Moreover, the temperature distributions of three kinds of filler wire could be estimated using a proposed simple estimation method.