抄録
In this study, the fatigue properties of friction stir welded joint used A6061 and A2024 Aluminium alloys were evaluated. In order to consider the fatigue properties, fatigue tests were conducted at stress ratio R=-1, cyclic speed 23.3 Hz with plane bending fatigue condition. And then hardness distribution, fracture position, microstructure, crack growth behavior were investigated. As a result, hardness distribution and fracture position were corresponded in A2024 and A6061 FSW joints, but were not corresponded A6061/A2024 dissimilar FSW joint under the influence of microstructure. And surface crack growth behavior of A6061/A2024 dissimilar FSW joint showed same tendency of A6061 FSW joint. However, S-N behavior of A6061/A2024 dissimilar FSW joint showed same tendency of A2024 FSW joint. The reason for this, the influence of micro-crack growth behavior from crack initiation to 0.3mm.