Multi Objective Optimization of Friction Stir Welding Parameters for Joining of Two Dissimilar Thin Aluminum Sheets

The article presents multi objective optimization of parameters affecting weld quality in tailored friction stir butt welding of 2.0 mm thin dissimilar sheets of AA5052-H32 and AA5754-H22 using Taguchi grey based approach. The L9 orthogonal array has been used to design the experiments, and the experiments have been conducted in a laboratory stage vertical milling machine by varying tool rotational speed, worktable translational speed, tool shoulder diameter and tool pin geometry. After welding, the weld strength and percentage elongations have been evaluated using uniaxial tensile test. Based on the experimental data, empirical relations among the parameters correspond to each output feature has been developed using simple regression method. Optimum levels of parameters have been identified using grey relation grade.