Structural T-joint produced by means of friction stir welding (FSW) with filling material

In this paper the Friction Stir Welding process (FSW) is used to obtain a T-joint of two sheets on an extruded profile all made by AA6082-T6 aluminium alloy. The extruded profile has an appendix in the upper zone that acts both as positioning reference for the sheets and filling material. In the experiments, several PIN shapes and process parameters are investigated in order to produce a sound weld. A strict temperature control was realized by means of nine k-types thermocouples (five on the sheets and four inside the extruded profile) in order to monitor the temperatures distribution all along the joint. Several specimens were extracted from the different experimental conditions, then tensile tested, while optical microscope analysis and micro hardness measurements were performed in the cross section in order to investigate the material flow and the presence of defects.