The investigation of mechanical and microstructural properties of friction stir welded AA7075/AA6061 joints

Aluminum alloys which are difficult to join by conventional fusion welding techniques and increasingly employed in many important manufacturing areas, such as aircraft, space and defense industries can be joined by a new technique, namely friction stir welding process.In this study, two different Al alloys i.e. AA6061 and AA7075, were welded by friction stir welding process. Considering the literature the welding conditions (rotational speed, traverse speed and tool geometry) were chosen and, the joints having different mechanical and microstructural properties were produced. It was shown that the weld parameters played an important role on the welding quality. It is possible to increase the weld quality of friction stir welded joints by using appropriate combination of the rotational speed and traverse speed.In the first chapter of this study, the subject was introduced. In the second chapter, the aluminum and its alloys were introduced. In the third chapter, the welding methods used for Al alloys were discussed. In the fourth chapter, the friction stir welding processes were presented extensively. In the fifth chapter, the place of this study in the literature was discussed. In the sixth chapter, the method of experimental study and the preparation phases of the experiments were presented. In the seventh chapter, the experimental results were given and discussed in details. In the eighth and final chapter, the general results and recommendations were given.