High-temperature deformation of ZrO2Al2O3/SiC whisker composites fabricated by two techniques

ZrO2Al2O3/SiC whisker-reinforced composites, with whisker volume fractions of 0%–28%, fabricated both by powder and precursor processing, have been deformed at temperatures of 1300–1500 °C under constant compression rates of 1.7 × 10−5 to 6.8 × 10−5 s−1. Above 1400 °C, a stress at which the work-hardening rate became zero could be measured and correlated with whisker content. On the contrary, at 1300 °C all samples broke within the elastic regime. At 1350 °C, increased whisker content appeared to inhibit fracture, so plastic behavior was obtained for samples containing 28% SiC. In the range of temperatures and compression rates, noted above, stress exponents were determined and tentatively correlated with microstructural features and their evolution during plastic deformation.