The joint strength and subsequent microstructural evolution of a friction stir spot-welded AA6061-T6 alloy was investigated according to the process parameters: tool rotation speed, dwell time and pin angle of the tool. A maximum tensile shear load of 2.78 kN was obtained from the joints generated under a combination of process variables like 1000 and 1500 rev min−1, 5 s, 5°. Under a fixed pin angle of 5° and a rotational speed of 1000 rev min−1, an increase in dwell time from 1 to 5 s resulted in a considerable increase in tensile shear load. An empirical process map under a fixed tool design is proposed to determine a feasible range of process conditions.
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