Oxidation mechanism and resistance of ZrB2-SiC composites

The oxidation mechanism of ZrB2-SiC composites was investigated based on a combination of theory and experiments. The oxidation reactions, microstructure evolution, scale stability and temperature limit were examined in our research and a good correspondence was obtained between theoretical predictions and experimental results. Microstructure evolution and stability are significantly dependent on both temperature and composition. SiO2 is thermochemically stable below 1800 degrees C and will lose its protective properties at temperatures above 2300 degrees C. The temperature limit for ZrB2-SiC composites is strongly dependent on the vapor pressure of the gaseous products and volume content of ZrB2. (C) 2009 Elsevier Ltd. All rights reserved.