Effect of rotation speed on mechanical properties and microstructure of friction stir spot welding (FSSW) Al 5052 - Steel SS400

Abstract

In this study, the effect of welding parameter such as rotational speed on the mechanical properties and microstructure of friction stir spot welded Al 5052 and SS400 sheet have been investigated. The rotation speed of 1250, 1600, 2000 rpm and the dwell time of 10, were applied to fabricate the friction stir spot welded joint. The microstructure of the joint was observed using scanning electron microscope (SEM). The tensile shear load was measured using by universal testing machine. Base on the microstructure observation showed that the thickness of IMC increases due to the increase of rotational speed. The Maximum thickness of IMCs reached 7.15 μm at 2000 rpm. The result of the tensile shear test showed that the rotational speed is affecting the mechanical properties. The increase of tool rotation speed from 1250 up to 1600 rpm caused the increase of tensile shear load, however further increase up to at 2000 rpm resulted in the decrease of the shear tensile load. The highest shear tensile load reaches 2810.07 N at 1600 rpm.