Mechanical Properties and Electrical Resistivity of the Friction Stir Spot-Welded Dissimilar Al–Cu Joints

Abstract

Alternative methods for dissimilar metal joining particularly aluminium and copper have gain interest in manufacturing sectors. Friction stir spot welding was carried out on the AA6061 and C11000 wires of 2 mm diameter. This research paper reported the results on microstructures and mechanical properties of the spot-welded joints, and also special attention is provided for electrical resistivity of the welds. The microstructures reveal the information of grain structure and bonding. The width of diffusion layer significantly reduced with low dwell times. For a plunge depth of 1 mm, the maximum tensile strength (294 MPa) is achieved during the higher rotational speed (1400 rpm). For the same plunge depth, lower tensile strength values are exhibited by the joint produced using the lower rotational speed (800 rpm). Hardness of the weld region recorded 70 HV which is less than Cu (115 HV) and greater than Al (40 HV). FSSW joints (0.30 to 0.34 μΩ) offered higher range of electrical resistivity than that of base metal (0.02 μΩ). The results highlighted in this paper might be helpful for both academic researchers and industrialists.