Dissimilar Al to Mg Alloy Friction Stir Welds

Abstract

In the present study the microstructure and properties of a dissimilar friction stir weld between the magnesium alloy AZ31 and the aluminium alloy 6040 have been investigated. The intermetallic leads to a loss of strength and ductility of the join. In this study optical and scanning electron microscopy as well as energy dispersive spectroscopy (EDS) have been used to analyse the join interface as well as workpiece residues bonded to the joining tool. Dynamic recrystallisation was observed in the stir zone resulting in a substantial reduction in grain size particularly for the Al base material.