Production and mechanical properties of Al2O3 particle-reinforced 2024 aluminium alloy composites

2024 aluminium alloy metal matrix composites (MMCs) reinforced with three different sizes and weight fractions of Al2O3 particles up to 30 wt.% were fabricated by a vortex method and subsequent applied pressure. The effects of Al2O3 particle content and size of particle on the mechanical properties of the composites such as hardness and tensile strength were investigated. The density measurements showed that the samples contained little porosity, and the amount of porosity in the composites increased with increasing weight fraction and decreasing size of particles. Scanning electron microscopic observations of the microstructures revealed that the dispersion of the coarser sizes of particles was more uniform while finer particles led to agglomeration of the particles and porosity. The results show that the hardness and the tensile strength of the composites increased with decreasing size and increasing weight fraction of particles.