Influence of Tool–Base Metal Interference on the Performance of an Aluminium–Magnesium Alloy Joined via Bobbin Tool Friction Stir Welding

Bobbin tool friction stir welding (BTFSW) is a variant of the FSW process which uses special two-shoulder that forms top and bottom weld surface. As such, significant simplification setup achieved. One dominant parameters BTFSW interference between shoulder pinch gap metal thickness. In this research, influence square pin with convex shoulders on temperature, microstructure, tensile, impact, bend performance were studied, appropriate correlations devised. The base was an aluminum–magnesium alloy in varied range 0.1 to 0.5 mm. Wormhole defects irregularities found all specimens except specimen welded 0.4 mm interference. An optimal resulted best mechanical properties, which, terms tensile strength reduction area, similar metal. Furthermore, impact significantly higher, attributed grain refinement effect nugget zone.