Microstructural studies and parametric optimization of dissimilar friction stir welds

Abstract As an alternative to fusion welding, FSW (Friction Stir Welding) is a unique solid-state welding technique that creates heat by friction between a non-consumable spinning tool and material substrate. The aluminium alloys (AA 2014 and AA 6082) have gained widespread recognition in the manufacture of light-weight structures. The mechanical and microstructural qualities of welded joints are appreciably influenced by welding process attributes namely tool spindle speed, pin geometry, and welding speed. The study centres on microstructural characterization and optimization means, mathematically developing a model to envisage tensile strength and micro hardness of dissimilar welds. Taguchi L9 orthogonal array with three factors and three levels was employed to carry out the experimentation. ANOVA and GRA (Grey Relational Analysis), dual technique based optimization approaches were used to signify the proposed mathematical model. For dissimilar joints, the best welding settings to optimize tensile strength and hardness were determined and presented here.