The Effect of Tool Geometry of Friction Stir Spot Welding on the Mechanical Properties and Microstructure of AA6061-T6 Aluminum Alloy

Abstract

The effect of tool geometry in friction stir spot welding of AA6061-T6 aluminum alloy sheets was investigated in this research paper. Two different tool pin profiles simple cylindrical and conical with 12 mm and 16 mm shoulder diameters for each tool were studied in friction stir spot welding (FSSW). During the experiment, 1.8 mm thick workpieces were used. The welding processes were carried out at the room temperature. Four lap-shear specimens were performed for each welding condition, three specimens were used for the lap-shear tensile tests to evaluate the average value of the tensile shear failure load. The FSSW specimens that performed at different tool geometries were tested for the micro-Vickers hardness and examined for the microstructure. The study found that the best results were obtained by using the conical pin tool with the 16 mm tool shoulder diameter.