Transient Three-Dimensional Analysis of Gas Tungsten Arc Welding Plates

In this study, a numerical scheme of Douglas-Gunn is employed to solve the three-dimensional transient heat conduction problem in welded plates. The heat transfer characteristics as well as the physical properties of base materials for this problem are affected by the moving heat source powered by input voltage. Therefore, to simulate the real situations, the intensity of the heat source is assumed to follow a Gaussian distribution in spatial coordinates. Various parameters such as heat input, welding speed, radius of heat source, dimension, and material of the welded plates are considered. In the welding of thin plates, the welding problem can be mostly assumed to be two-dimensional in heat transfer if full penetration of the weld pool is obtained. In addition, good quality of welding is obtained if the workpiece is properly preheated in welding 6061 aluminum plates. Finally, a series of experiments is conducted to verify the theoretical results.