Fabrication and investigation of mechanical properties of Magnesium -Alumina-Boron Carbide hybrid metal matrix composite by powder metallurgy technique

Abstract A novel hybrid Metal Matrix Composite (MMC) was synthesized by reinforcing pure Magnesium (Mg) with α -Alumina (Al 2 O 3 ) and Boron carbide (B 4 C) particles in varying weight fractions of 5%, 10%, and 15% using the powder metallurgy (P/M) route, followed by sintering in a tubular furnace. The mechanical behavior of the composites was systematically evaluated in terms of microhardness, wear resistance, density and porosity. Among the tested compositions, the MMC with 15% reinforcement exhibited the highest performance, achieving a microhardness of 49.7 HV and the lowest wear rate of 1.4105 × 10 −10 m −3 m −1 under a 5 N load, indicating enhanced resistance to material loss. Microstructural examination via Scanning Electron Microscopy (SEM) revealed a homogeneous dispersion of the reinforcing particles within the Mg matrix, coupled with reduced porosity and minimal micro voids, contributing to the improved mechanical properties. Energy Dispersive X-ray Spectroscopy (EDS) analysis confirmed the successful incorporation of Mg, Al, B, O, and C elements, validating the presence and uniform distribution of the reinforcement phases. These findings demonstrate the potential of Al 2 O 3 and B 4 C reinforced Mg-based hybrid composites for applications requiring lightweight materials with enhanced wear and hardness characteristics.