Oxidation of ZrB2 Ceramics Containing SiC as Particles, Whiskers, or Short Fibers

The thermal stability of ZrB2-based composites containing SiC-chopped fibers was tested in a bottom-up furnace at 1200°C, 1500°C, and 1700°C for 30 min. The oxidation behavior was studied by X-ray diffraction, scanning electron microscopy, and weight gain. The degradation induced by oxidation was also evaluated considering the strength decrease of oxidized bars. Baseline ZrB2-composites containing the same amount of SiC particles or SiC whiskers were tested in the same conditions for comparison