Tensile behaviour for aluminium alloy (6061) in single & double pass friction stir welding by using different tool shapes

In this experimental work, an extensive investigation had been carried out on Al Alloy(6061). In this work the speed of tool rotation were taken as 3080 rpm, transverse speed as 30mm/min. and tool tilt angle was taken as 2⁰. In both single and double pass, the highest tensile strength of the joints was obtained by using the square pin profile tool. The square pin profiles tool is best and tensile strength significantly decreases for, cylindrical, triangular and threaded pin profile tool due to defect formation. In double sided weld, the joints fabricated by cylindrical pin profiled tool showing almost matching tensile properties to that of square pin tool profile.