EFFECTS OF REINFORCEMENT PARTICLE SIZES ON MECHANICAL PROPERTIES OF ALUMINIUM/EGG SHELL COMPOSITES

Abstract

The 100 and 150 m sized CaCO₃ particles (sourced from eggshells) from 2-12 wt.% by were used as reinforcements for the fabrication of Al ceramics composites using compo cast technique. The technique involves manual stirring of Al alloy melt-CaCO₃ particle mixture prior to pouring process. The morphology of the CaCO₃ particles and Al alloy/CaCO₃ composites were examined using scanning electron microscope (SEM). The mechanical properties of the fabricated Al alloy / CaCO₃ composites were investigated. The result obtained from SEM analysis revealed that the microstructures of Al alloy/100 m CaCO₃ composites are finer than those of their counterparts. This justifies better interaction of 100 ?m with Al alloy than 150 ?m CaCO₃ particles which may be attributable to particle diffusion enhancement due to a decrease in the particle size. Al alloy/100 m CaCO₃ composites displayed higher tensile strain than Al alloy/150 m CaCO₃ composites. Hence the use of 100 m sized egg shell particles for reinforcement has experimental proven advantages over 150 m sized CaCO₃ particles.