Relationship between Microstructure and Tribological Properties for Al2O3/SiC Nanocomposites

Abstract

Many mechanical properties of nanocomposites such as Al2O3/SiC, Si3N4/SiC and MgO/SiC have been reported. However, a few researches on the tribological properties of nanocomposites have been performed. In the present work, the relationship between tribological properties and microstructure of Al2O3/SiC nanocomposites was investigated using reciprocal ball-on-plate tribometer. Al2O3/SiC nanocomposites were fabricated by hot pressing at 30 MPa for 1 h in an Ar gas atmosphere. The microstructure of the nanocomposites was regulated by variations in sintering temperature. As sintering temperature increased, grain size of Al2O3/SiC nanocomposites was increased, whereas aspect ratio was decreased, showing grain shapes transited from elongated to circular grain feature. Wear rate increased by increases in sintering temperature. Therefore, tribological behavior of Al2O3/SiC nanocomposites was associated with both grain size and shape.