An Investigation of the Microstructure and Mechanical Properties of B₄C Reinforced PM Magnesium Matrix Composites

Abstract

Due to their excellent properties such as high specific stiffness, strength/weight ratio, and wear resistance, metal matrix composites (MMCs) with particulate reinforcement and related manufacturing methods have become important research topics in recent years. Magnesium MMCs are materials that are commonly used for fabrication of light-weight functional components. Magnesium MMCs that are reinforced with various fractions of B₄C (3, 6, and 9 wt.%) were fabricated by powder metallurgy (PM) technique using a sintering cycle in a vacuum furnace at 590 ⁰C for 9 h. A qualitative analysis of X-ray diffraction (XRD) patterns indicated the formation of Al₂O₃, MgO, and MgB₂ phases in the structure of Mg/B₄C MMCs. The sintered density of the MMCs decreased with an increase in the amount of B₄C addition. The hardness of the MMCs was found to be higher than that of unreinforced Mg. The compressive test results also showed a significant effect of 3 wt.% B₄C content on the compressive strength of magnesium MMCs manufactured by the PM technique..