Effect of ZrC and ZrO2 Additions on the Microstructure and Properties of ZrB2–SiC Ceramics

Abstract

We have studied the effect of ZrC and ZrO2 additions on the microstructure and properties of ceramic composites based on ZrB2???5% SiC, produced by pressure-sintering mechanically activated powders at a temperature of 1600??C. The results demonstrate that the addition of ZrO2 increases the density, hardness, and fracture toughness of ceramic composites based on ZrB2???5% SiC. In particular, the KIc of the ZrB2???5% SiC ceramic is 4.6 ?? 0.3 MPa m1/2 and that of the composite containing 20% ZrO2 is 7.3 ?? 0.4 MPa m1/2.