Influence of distinct tool pin geometries on aluminum 8090 FSW joint properties

Abstract. Aluminum Lithium alloys are recuperating substantial interest from automotive and aerospace industries owing to their extraordinary specific strength as compared conventional aluminum (2xxx, 6xxx, 7xxx) alloys. The goal of the present investigation is study AA 8090 joints produced with unique solid-state welding technique friction stir (FSW). Tool pin profile induces remarkable influence on further plastic deformation during FSW. Therefrom, influences three distinct but constant dynamic area conditioned tool geometries namely, square trapezoidal, hexagonal threaded taper resulting material flow patterns, mechanical properties, microstructure have been studied discussed in detail. FSW joint trapezoidal geometry delivered highest resistance grain refinement almost flawless microstructure.