Friction Stir Welding of Different Aluminum-Silicon Alloy Compositions Utilizing Conventional Vertical Milling Machine

Abstract

Friction-Stir Welding (FSW) is a solid-state procedure for welding two plates in which there is relative motion between the tool and workpiece, which creates the heat required for the material of the two edges to join by atomic diffusion. The present research article focuses on friction stir welding of dissimilar aluminum-silicon alloys utilizing a vertical milling machine and altering process parameters. Moreover, testing is done on the weld joints for the best process parameter. The process parameters considered in the present work for joining dissimilar aluminum alloys primarily were a constant tool feed rate of 63 mm/min and three varied tool rotational speed rates of 710, 1000 and 1400 rpm. Mechanical characterization of weld joints, such as tensile, hardness, microstructural studies and surface roughness tests, were used to identify the most optimal parameter. The results indicated that Al-Si alloys having Al-5%Si with Al-12%Si  FSW joints welded using 1000 rpm tool rotational speed proved to have better hardness and lesser surface roughness while, Al-Si alloys having Al-12%Si with Al-17%Si  FSW joints, had better hardness and roughness properties when welded using 1400 rpm tool rotational speed. Concerning the ultimate tensile strength, Al-Si alloys having Al-5%Si with Al-12%Si and  Al-12%Si with Al-17%Si  FSW joints welded using 1400 rpm tool rotational speed offered better results.