Enhancing Material Performance: A Review of Magnesium-Based Metal Matrix Composites

Magnesium Matrix Composites (Mg-MMCs) are emerging as highly promising materials for aerospace and defence applications due to their low density and favourable mechanical properties. Compared to conventional engineering materials, these composites exhibit improved specific strength, stiffness, damping behaviour, wear resistance, creep, and fatigue properties when reinforced with various elements. This paper provides an overview of the effects of different reinforcements in magnesium and its alloys, highlighting their advantages and drawbacks. Key phenomena such as interfacial transition, agglomeration effects, fibre-matrix bonding, and particle distribution challenges are discussed in detail. The impact of reinforcements on microstructure and mechanical properties, including tensile strength, yield strength, ductility, strain, hardness, wear, and fatigue, is critically analyzed. The study also reviews processing techniques, characterization, and the tribological and mechanical behavior of Mg-MMCs, with a focus on reinforcements like carbon nanotubes (CNT), carbonaceous materials, fullerenes, SiC, Al2O3, TiC, B4C, and graphene. Observations indicate that ceramic reinforcements enhance hardness and strength but reduce ductility, whereas titanium-based metallic reinforcements improve both ductility and strength. Significant applications of various magnesium MMCs are also examined.