Investigation of Compressive Creep Behaviour of Die-cast MRI153M and MRI230D Magnesium Alloys

Abstract

Two Mg-Al-Ca containing alloys MRI153M and MRI230D have been developed by high pressure die casting. The as-cast microstructures of MRI153M alloy consists of primary Mg (α-Mg), Mg17Al12 and (Mg,Al)2Ca (C36) phases, whereas, the MRI230D alloy consists of α- Mg and (Mg,Al)2Ca (C36) phases. The MRI230D alloy exhibited superior creep resistance as compared to that of MRI153M alloy. The microstructures of both the alloys following creep test revealed increased amount of C36 phase. However, the quantity of pre-existing Mg17Al12 phase in the MRI153M alloy has increased, which is responsible for inferior creep resistance in MRI153M alloy. The additional precipitation of C36 phase during creep test resulted in improved creep resistance in MRI230D alloy.