Evaluating the Durability of SiC-Coated Carbon Composites Under Thermal Shock Conditions

Oxidation and indentation properties of silicon carbide-coated carbon composites were investigated to analyze its durability under atmospheric thermal shock conditions. The silicon carbide-coated samples were prepared either with chemical vapor deposition or chemical vapor reaction/chemical vapor deposition hybrid coating. The remnant weight of uncoated and coated samples was investigated after each thermal shock cycle. The surface and cross-section of coated samples were then analyzed to confirm morphological changes of the coating layers. The spherical indentation test for uncoated and coated samples were also performed. As a result, silicon carbide coating improved the oxidation resistance, elastic modulus, and hardness of carbon composites. Hybrid coating drastically enhanced the durability of samples at high temperature in atmospheric conditions.