This paper presents a three-dimensional simulation of stationary gas tungsten arc welding which studies the development of the arc and weld pool in three types of joints, namely L-shape, V-shape and open-corner. Temperature, heat flux, current density and gas shear stress are determined in the arc and are used as input to the workpiece to determine the heat, fluid flow and weld pool shape. Buoyancy and surface tension gradient which affect the pool shape are taken into consideration.

In this paper, a three-dimensional (3D) numerical simulation is performed on a stationary arc to study the effect of torch angles in gas tungsten arc welding (GTAW) of SS304 stainless steel. A comparison has been made to investigate 90 and 70° torch angles and analyze the effect on arc and weld pool shape. Current density, heat flux, and gas shear stress are calculated in the arc region and are used as input to the workpiece to determine the weld pool. Also, both buoyancy and Marangoni shear affect the weld pool shape and are taken into account.

In this study, the effect of different tip angles (30°, 60°, 90° and 120°) on the arc and weld pool behavior is analyzed in 2 mm and 5 mm arc lengths with tilted (70°) torch. Arc temperature, velocity, current density, heat flux and gas shear are investigated in the arc region and pool convection and puddle shapes are studied in the weld pool region. The arc temperature at the tungsten electrode is found the maximum with sharp tip and decreases as the tip angle increases. The arc temperature on the anode (workpiece) surface becomes concentrated with increase in tip angle.