Microstructure and Mechanical Properties of SiC-Al₂O₃ Nanocomposite Prepared by Surface Modified SiC Nanopowders

Abstract

SiC nanopowders were surface modified by low temperature plasma polymerization. 5vol% SiC-Al2O3 nanocomposite was prepared by adding the surface modified SiC nanopowders into the matrix of Al2O3.The influence of surface modified SiC nanopowders on the properties and structure of SiCAl2O3 nanocomposite was studied. The surface modified SiC-Al2O3 nanocomposite had higher density and nicer mechanical properties than untreated SiC- Al2O3 nanocomposite because of the improvement of dispersion. The hardness and toughness of the SiC- Al2O3 nanocomposite were higher than monolithic Al2O3 but the ultimate bending strength was not perfect because of retardation of the densification and formation of unsintered pores caused by the induced oxygen during the process of powder treatment.