A Comparative Analysis of the Weld Pools Created with DC Single-, DC Double-, and PC Double-Electrode Configurations in Autogenous GTAW

Three different Gas Tungsten Arc Welding methods – DC single-electrode, DC double-electrode, and PC double-electrode – were analyzed using SS304 steel as the base material. Numerical models were developed to simulate the arc plasmas and calculate heat flux, current density, and wall shear stress on the surface of the workpiece. These data served as input for simulating the weld pools across all three configurations. Experimental validation showed a good agreement with the numerical results. In the double-electrode setup, electromagnetic interaction caused the arcs to deflect, which resulting an 8% reduction in the maximum heat flux and a 4% decrease in the maximum current density. Marangoni stress had a notable effect on the weld pool shape, creating a w-shaped stationary pool with the single-electrode setup, whereas the pool reached its greatest depth with the stationary double-electrode configuration. With the moving weld pool, the DC double-electrode created a pool that was 41% deeper and 25% wider compared to the DC single-electrode setup. The PC double-electrode created a pool that was 40% deeper and 22% wider than the DC single-electrode configuration. The findings of the research offer guidance for enhancing different arc settings and electrode arrangements to attain the intended welding quality and performance.