Solidification Mechanism of the Melt Conditioned Twin Roll Cast Magnesium Alloy

Abstract

Twin roll casting (TRC) has been demonstrated to be a process capable of producing Mg sheets at a significantly reduced cost. However, the quality of the Mg sheets produced by the TRC process is limited due to the formation of coarse columnar grains and severe centreline segregation, which reduces both the strength and ductility of Mg-alloys. In this paper, melt conditioned (MC) has been employed prior to twin roll casting (TRC) of AZ31 alloy to understand its effect on the solidification mechanism. For comparison, AZ31 alloy strips were also produced through conventional TRC process. The results showed that the solidification mechanism can be completely altered by introducing MC in TRC process.