The Characteristics of Alumina Particle Reinforced Pure Al Matrix Composite

Al2O3 is widely used as the reinforcing additive in the metal matrix composites. The influence of Al2O3 particle size on the density, hardness, microstructure, yield stress, compression strength, and elongation of the sintered Al–Al2O3 composites were investigated. In the present study, 10 wt % of Al2O3 powder with three different particle sizes (3, 12 and 48 µm) were used in the production of the samples. Powder metallurgy technique was utilized to obtain more homogeneous Al2O3 distribution across the composites. The samples were cold pressed at 440 MPa, and sintered at 550 ◦C for 45 min. Results showed that the relative density of the composite was initially increased with decreasing particle size. However, it was decreased with further particle size reduction. It was also pointed out that the mechanical properties of the specimens were increased with decreasing particle size. The grain size and particle distribution homogeneity was decreased with raising the particle size. PACS: 81.05.Ni 1