Numerical Analysis of In-Process Heat Transfer and Material Flow During Dissimilar Friction Stir Welding Process

Abstract

Abstract Friction stir welding (FSW) has been successfully applied to join dissimilar materials in engineering applications. Fundamental understanding on the underlying physical principles of the dissimilar FSW process is generally required to achieve strong and reliable joints. In this study, we aim to develop a theoretical and numerical model based on computational fluid dynamics (CFD) in order to analyze the in-process heat transfer and material flow during the dissimilar FSW of aluminum and steel. The model describes the coupling behavior between the material distribution, thermal-mechanical properties, interfacial friction, heat generation and transfer. To account for the different material behaviors in stirring zone, a VOF-based approach is adopted. In this paper, preliminary numerical simulation is conducted. Simulation results show that the current modeling approach has the capability to capture the material mixing during the dissimilar FSW of aluminum and steel. The predicted temperature field is shown to be asymmetrical, which is attributed to the different properties of aluminum and steel. The predicted thermal history agrees with the experimental measurements in the literature.