Improvement in strength and ductility of flame-retardant magnesium alloy through uniaxial hot pressing

Abstract. Flame-retardant magnesium alloys containing calcium element are attracting attention from aircraft and automotive industries because of their low density and high ignition temperature. Though thermomechanical treatments such as hot extrusion are effective to increase their mechanical properties, they cause an increase in cost. Present study focusses on commercial Mg-6Al-0.4Mn-2Ca and Mg-9Al-1Zn-2Ca alloys. Simple uniaxial hot pressing process is performed in these magnesium alloy plates. Tensile tests at room temperature revealed that the hot pressed Mg-6Al-0.4Mn-2Ca and Mg-9Al-1Zn-2Ca alloys have high tensile strength and elongation. Microstructural observation clarified that the improved mechanical properties were mainly due to dynamic recrystallization during the hot pressing. The present uniaxial hot pressing process has a potential as a simple thermomechanical treatment process for flame-retardant magnesium alloys.