Investigation of arc characteristics and weld formation in ultrasonic-magnetic coaxial hybrid GTAW

This paper aims to enhance the efficiency of the utilization of arc energy by adding ultrasonic and magnetic fields. A new welding method is proposed and named as ultrasonic-magnetic coaxial hybrid gas tungsten arc welding (U-M-GTAW). In this paper, the effect of tungsten extension and welding current on the arc characteristics under different welding methods and the effect of different welding methods on the 304 stainless steel weld formation were investigated. The arc shape changed significantly with increasing tungsten extension, and the addition of ultrasonic waves can increase the arc energy and stiffness. As the current increases, the arc area increases, and the degree of contraction and rotation of the arc decreases. Compared to the weld penetration of GTAW, U-GTAW and M-GTAW increased by 58.6% and 11.5%, respectively, while the weld penetration of U-M-GTAW decreased slightly. Compared with the weld width of GTAW, U-GTAW increased by 97.1%, M-GTAW increased by 44.5%, and U-M-GTAW increased the most by 123.8%.