Reactive Hot Pressing of <scp> <scp>ZrC</scp> </scp> – <scp> <scp>SiC</scp> </scp> Ceramics at Low Temperature

Abstract

Composites of ZrC – SiC with relative densities in excess of 98% were prepared by reactive hot pressing of ZrC and Si at temperature as low as 1600°C. The reaction between ZrC and Si resulted in the formation of ZrC 1− x , SiC , and ZrSi . Low‐temperature densification of ZrC − SiC ceramics is attributed to the formed nonstoichiometric ZrC 1− x and Zr – Si liquid phase. Adding 5 wt% Si to ZrC , the three‐point bending strength of formed ZrC 0.8 –13.4 vol% SiC ceramics reached 819 ± 102 MPa with hardness and toughness being 20.5 GPa and 3.3 MPa·m 1/2 , respectively.