EVALUATION OF ELECTRO-MECHANICAL PROPERTIES OF FRICTION STIR WELDED AL / CU BIMETALLIC LAP JOINTS

Friction stir welding Processes (FSWP) is a sophisticated solid state welding technology to join dissimilar and similar materials. Commercially pure Aluminium and Copper plates were joined using FSWP and the mechanical and electrical properties of bimetallic lap joints have been evaluated by changing the input processes parameters. Number of experiments was performed to obtain the optimum joint properties by adjusting angle of tool tilting, rotational and welding speeds. The experiments were carried out using design of experiments (DoE) to minimize number of experiments. The present paper provides a very valuable information on electromechanical behavior of Al to Cu dissimilar joints used for a critical application i.e. heat sinks, high voltage bus bars and heavy duty earthing strips, etc. It has been observed that high quality welds are obtained at low rotational and welding speeds irrespective of tilting angle. The maximum value of tensile shear strength is 70 MPa. The hardness is uniform throughout the joint. In manufacturing condition the resistance of the joint is negligible.