Numerical study on the short circuit aluminum alloy MIG welding metal transfer behavior including the influence of wire feeding and melting

Abstract

This study presents a comprehensive numerical investigation into the short-circuit transfer behavior in aluminum alloy metal inert gas (MIG) welding, focusing on the coupled interactions among arc plasma dynamics, droplet transfer, and molten pool flow. A multi-physics model was developed to simulate the transient dynamics of droplet transfer, incorporating wire melting kinetics and continuous feeding mechanisms. The model integrates arc-droplet-pool interactions and metal vapor transport phenomena, providing a detailed analysis of the short-circuit transfer process. It reveals significant dynamic changes in arc temperature and current density fields during the short-circuit transfer, which influence the wire heating and melting. The flow fields of the droplet and molten pool are influenced by electromagnetic forces, surface tension, and gravity, leading to complex flow patterns and pressure variations within the droplet. Experimental validation using high-speed video imaging confirmed the accuracy of the simulated droplet shapes and transfer behavior. This research lays a foundational theoretical framework for further numerical simulations of short-circuit transfer in aluminum alloy MIG welding, offering insights into optimizing welding stability and quality.