Fabrication and properties of ZrB2-SiC and ZrC-SiC composites by spark plasma sintering

ZrB2-SiC and ZrC-SiC composites were fabricated by spark plasma sintering at 1800 degrees C for 5 min under a pressure of 40MPa with ZrB2 powder, ZrC powder and SiC powder as the starting materials, respectively. The phase compositions, microstructures, and mechanical properties were investigated. The results show ZrB2-SiC composite is denser than ZrC-SiC composite. The relative density, an apparent porosity, and the bending strength of ZrB2-SiC composite are 97.9%, 1.08%, and 310 MPa, respectively, whereas those of ZrC-SiC composite are 89.7%, 1.20%, and 257 MPa. (C) 2014 The Ceramic Society of Japan. All rights reserved.