Influence of Welding Conditions on Microscopic Structure, Microhardness in conjunction with Corrosion Resistance in solid-state joining process between Dissimilar Al Alloys AA5754 to AA5052

4.0 mm thick cold-rolled AA5754 and AA5052 aluminum alloy plates were friction stir welded (FSW) under different rotation rates, welding speeds, and tilt angles. Tool pin profiles; cylindrical threaded, square, taper threaded, and triangular have been used to fabricate the joints. The influence of these welding parameters on microstructure, mechanical properties and corrosion resistances were investigated by means of the optical microscope (OM), scanning electron microscope (SEM), potentiodynamic polarization, and microhardness tests. The experiments are performed based on L16 orthogonal array considering the Taguchi technique for four design factors and four parametric levels. The welding parameters and tool pin profile play major roles in deciding the weld quality. This study reveals that the square pin profile tool creates welds that are both mechanically robust and free from metallurgical defects, outperforming other pin profiles. The square pin tool, when used with a rotational speed of 1000 rpm, delivers superior results, traverse velocity of 56 mm/min, and tool tilt angle of 4º gives high resistance to corrosion compared with other tool profiles.