Effect of Temperature Field and Pressure Force on the Inhomogeneity of 5754-H22 and 6082-T6 FSW Joints

The Friction Stir Welding (FSW) differs from the conventional welding process inter alia that the joint properties are not symmetric to the axis of joint line. Basically, it follows from the principle of the method because a rotary tool is used for welding. This asymmetry is due to created temperature field during welding, and the pressure force distribution along the thickness, so the investigation of these effects is important to create good quality welds. Experiments were performed on FSW joints made of non-heat treatable (5754-H22) and heat treatable (6082-T6) aluminium alloys, because there are clear difference between the reacts to these effect and show different changing on the microstructure. A special FSW tool was developed for the experiments and lowest inhomogeneity. Dynamic recrystallization and dynamic recovery can occur during welding so these were investigated by Gleeble material simulating system. During the experiments the grain sizes and grain shapes were also investigated.