Improvement of the oxidation resistance of a graphite material by compositionally gradient SiC/C layer

Mechanical Properties of Oxidation‐Resistant SiC/C Compositionally Graded Graphite Materials

“…From the above viewpoint, a compositionally graded graphite material has been developed that is composed of a surface CVD SiC coating layer, a SiC/C graded layer, and a graphite substrate. The SiC/C graded layer formed by in-pore diffusion reactions between carbon and gaseous SiO 5,6 has the function of reducing thermal stress concentrations at the interface between the SiC and the C. As previously reported, 7 this material exhibited much stronger adhesion of the CVD coating than that without the SiC/C graded layer during thermal cycling tests in air done by water-quenching from 1020°to 20°C.…”

“…The details of the procedure have been described in the literature. 5,6 The structure of the SiC produced by CVD was also ␤, and the coating thickness was about 100 m. Weight gain was observed owing to incorporation of Si atoms during the SiC/C graded layer formation. An average Si content was estimated from the following equation:…”

High Efficiency Thermal Energy Storage System for Concentrated Solar Power (CSP)

“…Enhancement methods for oxidation resistance of graphite materials have been extensively studied. Ceramic coatings are commonly employed to protect graphite materials from oxidation [28][29][30]. Although several coating systems have been developed, SiC is considered to be among the best due to its good mechanical properties, low density, excellent physical-chemical compatibility with graphite, and excellent oxidation resistance below 1800 °C [31].…”

Molten salt synthesis and antioxidation property of SiC‐coated mesocarbon microbeads

“…The oxidative damage of graphite structure components will lead to potential safety hazard for nuclear reactors, even catastrophic consequences. Preparing protective coatings is widely considered as an effect method to improve the oxidation resistance property of carbon/graphite materials at elevated temperature environment with oxygen 7–8 …”

“…Although all the mentioned methods successfully introduce SiC coating to the surface of matrix, some drawbacks can still be obviously noticed. For instance, the coatings fabricated via slurry method always exhibit a loose structure, which trends to become the diffusion path of oxygen and results in a poor antioxidation property 8 . The CVD technique is difficult to form a totally uniform coating on spherical graphite surface.…”