Preparation and characterization of high-performance ZrB2-SiC-Cf composites sintered at 1450 °C

ZrB2-SiC-C-f composites containing 20-50 vol% short carbon fibers were hot pressed at low sintering temperature (1450 degrees C) using nanosized ZrB2 powders, in which the fiber degradation was effectively inhibited. The strain-to-failure values of such composites increased with increasing fiber content, and the value for the composite with 50 vol% C-f was even more than 3 times higher than that of the composite with 20 vol% C-f. Furthermore, the composite exhibited non-brittle fracture mode when the fiber content was above 30 vol%, and the thermal shock critical temperature difference of the composite with 30 vol% C-f was up to 727 degrees C, revealing excellent thermal shock resistance of this composite. Additionally, ZrB2-SiC-C-f composites displayed good oxidation resistance when the fiber content was below 40 vol%, suggesting that this method provides a promising way for preparation of high-performance ZrB2-SiC-C-f composites at low temperature.