Equiatomic AlCoNi alloy matrix were reinforced by the dispersion of SiC nanoparticles (SiCnp) using the mechanical alloying process. The metallic powders were milled for 10, 20 and 30 h and sintered at 1200 0C under vacuum. Through particle size distribution, X-ray diffraction and scanning electron microscopy investigations, the mechanically alloyed powders for 10 h were selected to be reinforced with SiCnp (2.5, 5 and 10 wt.%). The microstructural features, and improvement in microhardness and porosity of sintered AlCoNi-SiC composites were investigated as a function of SiCnp content. Microhardness Vickers test showed that the enhanced microhardness of the AlCoNi-SiCnp composite could be attributed to the decrease of porosity in comparison to the AlCoNi alloy.
Keywords:
AlNiCo equiatomic system; composites; SiC nanoparticles; mechanical alloying; porosity
