Influences of pin profile on the macrostructure and mechanical properties of friction stir welded AA6061-T6 alloy T-joints

摘要

Friction stir welding is a solid-state process in which the joining operation is performed while the base materials are not melted and they are merely plasticized. In this study, friction stir welding of the AA 6061-T6 aluminum alloy T-joint has been studied and the influences of the tool pin profile on the macrostructure and mechanical properties of the joints have been investigated. Accordingly, three different pin profiles, such as straight cylindrical, taper cylindrical and square have been utilized. Then the joints have been examined using macroscopic images. Also, the joints have been investigated by tensile and hardness tests. As obtained from the results, the fabricated joints by the cylindrical pin exhibited the maximum tensile strength and hardness due to the homogeneity of material flow and the lack of defects.