Assessment of friction stir welding aluminium T-joints

Abstract Welds on AA 5083-H111 and AA 6082-T6 plates were performed in T-butt and T-lap configurations using three different tool pin geometries: tapered and threaded, quadrangular pyramidal and progressive pin, part threaded cylindrical and part pyramidal. Tunnel defects, kissing bond and oxides lines were observed in joints produced with the pyramidal pin tool and welds produced with the tapered pin tool only showed the presence of kissing-bond defects. The welds produced with the progressive tool did not reveal defects. No significant change in hardness was observed in all combinations of tool and joint geometry and the best mechanical performance was obtained with the welds produced with the progressive tool in the T-butt configuration. The T-butt joint configuration shows better FSW performance than the T-lap joint configuration.