Characterisation of Rapid Microwave-Sintered Mg/MgO Composite

Magnesium metal matrix composites are now been used in large number of structural applications. An attempt is made to synthesise pure Mg and Mg/5 wt% MgO (similar to 10 mu m) composite through powder metallurgy route assisted by rapid microwave sintering. The microwave sintering temperatures are varied at 450 degrees C, 500 degrees C and 550 degrees C, and different mechanical and physical characterisations of the composites are studied. The composites show improved properties with the addition of magnesium oxide as reinforcement. XRD investigations show that no reaction has taken place between magnesium and magnesium oxide at all sintering temperatures. At higher sintering temperature, few magnesium particles oxidise to form MgO. Microstructure shows well-distributed MgO particles in magnesium matrix. The addition of 5 wt% hard MgO particles improve hardness and increase 0.2% compressive yield strength (CYS) and ultimate compressive strength (UCS) than pure magnesium at all sintering temperatures.