Fluid and arc behavior with ultra high frequency pulsed GTAW

During ultra high frequency pulsed gas tungsten arc welding (UHFP-GTAW), the root radius of arc decreased with arc constriction that caused the narrower weld bead. The larger arc force created the more depression of surface, which had been important to increasing of weld penetration. Simultaneously, molten liquid metal is the key factor during welding process, and the mobility of molten pool was enhanced by weld behavior compared with conventional gas tungsten arc welding (C-GTAW). In the paper, the characteristics of arc behavior and fluid of molten pool was discussed with UHFP-GTAW. The results indicated the significant effect of the arc plasma on heat and force of molten pool with UHFP-GTAW. Further, the temperature diffusion of molten pool would reduce, which can limit the impact of arc heat on base metal effectively.