HIGH TEMPERATURE TOLERANT CERAMIC MATRIX COMPOSITES AND ENVIRONMENTAL BARRIER COATINGS

摘要

High-temperature machine components, more particularly, articles capable of operating in high-temperature environments, including for example turbines of gas engines, may be formed of a high temperature ceramic matrix composite that includes a ceramic substrate including silicon; an environmental harrier coating system including a silicon containing bond coat; and a diffusion barrier layer of a carbide or a nitride between the substrate of the article and the silicon bond coat of the environmental barrier coating system. The diffusion harrier layer selectively prevents or reduces the diffusion of boron and impurities from the substrate to the bond coat of the environmental barrier coating system.