The hybrid effect of SiC whisker coupled with ZrO2 fiber on microstructure and mechanical properties of ZrB2-based ceramics

ZrB2-based hybrid ceramics with SiC whisker and ZrO2 fiber (ZrB2–SiCw–ZrO2f) were hot-pressed at 1850 °C for 60 min under a uniaxial load of 30 MPa in Argon atmosphere. XRD analysis indicated no reaction of SiC whisker with ZrO2 fiber, and the optimal flexural strength and fracture toughness of the ZrB2–SiCw–ZrO2f ceramic were 680 ± 45 MPa and 8.0 ± 0.5 MPa m1/2, respectively. The improvement in toughness was mainly contributed to the whisker toughening, fiber toughening and the stress-induced transformation toughening, which could exhaust the fracture energy. The results presented in this paper indicated that ZrB2–SiCw–ZrO2f hybrid ceramic was a good candidate for ultra-high temperature structural application.