Friction Stir Welding (FSW) Studies of Dissimilar Al-Based Alloys Using Different Pin Profiles

The feasibility of friction stir welding (FSW) of Al 5083 and Al 6082 sheets using different pin profiles: straight cylindrical (Cy), threaded cylindrical (Th), triangular (Tr) and square (Sq) are studied, as cylindrical and threaded cylindrical generate regular stirring action whereas, triangular and square pin profiles produce pulsating stirring action in the flowing material due to their flat faces. Further in-depth investigations are made to understand the effects of these tool pin profiles on microstructures, hardness, crystallographic texture and tensile strength of the welded specimens. All specimens showed minimum hardness values in their heat affected zone in the AA 6082 side and they fractured as well in this region during the tensile tests. Having comparable microstructures and hardness values in all the specimens, only the threaded cylindrical joined specimen showed the lowest tensile strength due to the presence of maximum <001>tensile direction texture component in its heat affected zone