Tribological characteristics and optimisation of friction stir welded dissimilar aluminium alloys AA6082 & AA5052 using different tool pin profiles

In the present research, two dissimilar aluminium alloys, AA6082 and AA5052, were welded using Friction Stir Welding. Various tool pin profiles, including tapered cylindrical, pentagonal, and hexagonal, were used in this research. This research aims to examine the impact of various tool pin profiles on the mechanical properties and wear resistance of dissimilar joints. The tensile test reveals that the pentagonal welded sample exhibited a tensile strength of 101.45 MPa and joint efficiency of 74 %. The wear characteristics of the pentagonal welded sample displayed wear of 171 µm and frictional force of 6.9 N, resulting in a coefficient of friction of 0.345. Microstructure results revealed that the pentagonal tool pin profile had a well-formed and strong weld. Further, the process parameters were optimised using Response surface methodology based on the Box-Behnken design. Using the pentagonal tool pin profile, the parameters were optimised for specific wear, frictional force, and Coefficient of Friction. The optimised parameters identified are load of 20 N, a sliding distance of 1200 mm, and a sliding speed of 2 mm/sec with a frictional force of 6.48 N, Specific wear of 133.74 µm, and COF of 0.353. The confirmation test predicted a response error of under 3%.