Liquid Phase Sintering and Mechanical Properties of High Strength SiC

Abstract

SiC of 800 nm diameter, SiC of 30 nm diameter and Al2O3 of 200 nm diameter were mixed in a 0.05-0.6M-Y(NO3)3 solution. The SiC compact consolidated by filtration was hot-pressed at 1950oC in an Ar atmosphere. Addition of 30 nm SiC and alumina (1.2 vol%) to 800 nm SiC with Y2O3 enhanced the flexural strength to 1070-1080 MPa. The fracture toughness of the SiC decreased with increasing Y2O3 content.