Effect of Nano B4C on the Tribological Behaviour of Magnesium Alloy Prepared Through Powder Metallurgy

Abstract

In this present study, the particle size of as received magnesium alloy (AZ91) and B₄C powders was reduced through high energy ball mills. The combination of AZ91 (both 10 µm and 60 µm) reinforced with nano B₄C particles were fabricated by powder metallurgy technique. The incorporation of nano B₄C particles to the Mg matrix was done at various weight % such as 5, 10, 15 and 20. The AZ91 composites were fabricated in a suitable die set assembly and the green compacts were sintered in an electric muffle furnace at 500 °C with argon atmosphere for a dwell time of 1 h. The density of the composites was estimated using Archimedes principle. Micro hardness test was carried out for the prepared specimens and dry sliding wear test was conducted by using pin-on-disc apparatus at room temperature with varying loads and sliding velocities by keeping a constant Sliding Distance (SD). Among the various specimens, the composite with 10 µm size attained a higher Vickers hardness value as well as better wear resistant property. Worn surface analysis of the prepared composites was studied using Scanning Electron Microscope (SEM).