Taguchi-Optimized Friction Stir Welding of Aluminum Alloy AA2219: Investigating the Influence of Process Parameters on Mechanical Properties Via Grain Refinement

Mechanical properties of fusion welded joints can be improved by refinement of grain size. This study presents the effect of the friction stir welding process on grain refinements (grain size and grain morphology) of aluminum alloy AA2219-T o butt welded joints of gas tungsten arc welding (GTAW). Traditional cold working and heat treatment processes are compared and contrasted with a novel hybrid welding approach, which incorporates the use of Friction Stir Welding (FSW) in unification with the TIG welding. Our analysis encompasses to evaluating the impact of FSW process parameters on grain refinement (grain size and morphology), particularly rotational speed (RPM), traverse speed (feed), and tool pin geometry. Employing the multi-objective Taguchi method, these FSW parameters were optimized to yield superior mechanical properties and quality features. Our results highlight that the introduction of FSW as an adjunct to traditional GTAW, a process referred to as ‘Hybrid Welding’ in this study, can achieve notable grain refinement in the Aluminum alloy welded joints.