Mechanical Properties of Hot-Pressed Compacts Made by Alumina Particle Dispersion Magnesium Powders

Abstract

To enhance the mechanical properties of Mg alloys, powders of pure Mg (Al2O3/Mg) dispersed with over 10 vol% Al2O3 particles were formed by ball milling powder mixtures of pure Mg and Al2O3 particles with particle sizes of 0.3 and 1 μm. The effect of the Al2O3 content of hot-pressed discs of Al2O3/Mg powders on the mechanical properties was investigated. The hardness increased sharply at certain Al2O3 content. This is considered to be because of the development of Al2O3 particle strengthening due to the excellent interfacial bonding between Mg and Al2O3 particles when the Al2O3/Mg discs contain a sufficient amount of Al2O3 particles and have a sufficient interparticle distance. The maximum hardness was 220 HV. The tensile strength increased as Al2O3 content was increased. The Al2O3/Mg plate with Al2O3 particles sizes of 0.3 and 1 μm indicated maximum values of the bending strength at 10 and 14vol%Al2O3 content, respectively.