Preliminary study on the microstructure and mechanical properties of dissimilar joints of aluminum alloy and pure copper by FSW

Aluminum and copper are two common metals and Al-Cu joints are commonly used in the power industry. Overlay joints of 3105 aluminum alloy and commercially pure copper were produced by FSW, microstructure and mechanical properties was investigated. A combination of optical and scanning electron microscopy is used to characterize the microstructures in the copper and heat affected zone in the aluminum near the fusion line. The hardness distribution was analyzed and residual stresses were measured at the stir zone, copper side and aluminum alloy side.