Densification behavior and microstructure of spark plasma sintered ZrB2-based composites with SiC particles

The densification behavior and microstructure of spark plasma sintered ZrB2-based composites with SiC particles were examined. The effects of the amount and size of the SiC particles added were assessed. The results indicated that sinterability of the composites was improved by the addition of SiC compared with single-phase ZrB2 ceramics. This improvement depended on the effects of the amount and size of SiC particles added. Relative densities exceeding 98% were obtained for ZrB2–SiC powders sintered at 1900 °C for 2 min under a pressure of 30 MPa. The microstructure of the resulting composites was fine and homogeneous, and the average grain size of ZrB2 decreased with increase in the amount of SiC and with decrease in SiC particle size.