Droplet transfer of arcing-wire pulse GTAW

An arcing-wire pulse GTAW welding process was presented in this paper.Pulse current was added into the GTA electrode arc between the non-consumableelectrode and the workpiece.Besides the advantages of separation of heat and mass transfer with no spatter, this process technology could reduce the heat-affected zone and the burning of alloying elementsby controling the shape andthe penetration of welding pool with pulse GTAW. It was tested that with the reduction of the distancebetween the wire and the workpiece, the droplet transfer changed from big drops transition intonone arc contact transition.And the closer the distance was, the faster the droplet transfer frequency would be.When the wire was kept at a certain distanceto the workpiece, there was an optimal frequency that could achieve the minimum droplet size with the welding process ofone drop withone pulse.