Mechanical Properties and Microstructure of Underwater Friction Stir Welded AA5083-Cu Dissimilar Plates

Friction Stir Welding (FSW) is a solid-state joining process of metals such as copper and aluminium that has been known to generate large heat affected zones. To address this problem Underwater Friction Stir Welding (UWFSW) has been developed to reduce HAZ while enhancing weld strength. In this investigation, dissimilar plates of copper and AA5083 aluminum alloy were welded underwater using UWFSW which led to rapid cooling and higher weld hardness. The research sought to establish the effects of traverse speed, welding parameters and tool tilt angle on welded specimens. The mechanical properties and microstructural characteristics of the welded joints are compared systematically and analyzed. There may be potential advantages of UWFSW over conventional FSW for better weld quality and performance due to the use of underwater conditions in welding process. This work reveals insights into optimizing UWFSW parameters for effective joining dissimilar metals with enhanced weld integrity and mechanical properties requirements.