Performance Evaluation of High-Pressure Die-Cast Magnesium Alloys

摘要

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 ℃ 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.