New GTAW variant for high-throughput aluminum welding

Abstract

For aluminum joining, the gas tungsten arc welding (GTAW) and the gas metal arc welding (GMAW) processes are widely used. The GTAW process is mainly used when high quality is required whereas the GMAW process allows higher throughput at a lower quality. Therefore, aluminum fabricators have to compromise between a high quality and a high productive welding process thus far. In this paper, a new GTAW welding variant is presented that operates in DCEP polarity (electrode as the anode) at high currents up to 450 A. The use of a second gas stream ensures a strong penetration and good arc stability. The welding performance of the new GTAW variant is compared to AC GTAW and pulsed GMAW. It enables high-quality welds for a wide thickness range between 2 and 10 mm at even higher welding speeds compared to GMAW.