Performance evaluation of high-pressure die-cast magnesium alloys

Abstract

Over 90% of the magnesium (Mg) alloys in commercial applications are produced by high-pressure die-casting. This paper presents our efforts in evaluating castability and properties of commercial and near-commercial magnesium alloys to demonstrate how the currently available alloys can be applied to different situations across a range of property space. For high temperature applications, i.e. 175 °C and above, Mg–RE and Mg–Al–Ca based alloys have creep properties at least comparable to aluminium (Al) alloy A380 although these alloys have some challenges with casting or cost. For moderate temperatures, Mg–Al–RE based alloys, especially AE44, are most attractive due to an excellent combination of creep resistance, strength and castability. For automotive structural applications where a good combination of strength and ductility is required, Mg–Al alloys provide the baseline, but Mg–Al–RE based alloys can provide outstanding performance, especially with recent discoveries about its response to age hardening treatments. Therefore, high-pressure die-cast Mg alloys hold great promise for continued growth in automotive applications.