Thermal barrier coating system utilizing lcalized bond coat and article having the same

摘要

A thermal barrier coating system for a superalloy substrate is disclosed. The superalloy is preferably of the type that is capable of forming an adherent alumina layer. A bond coat is applied to a local area of the substrate (24), so that a portion of the substrate remains exposed. The localized area is defined to be the area(s) at which a TBC typically fails first, e.g., the leading (30) and trailing edges (32) of an airfoil (20), or other area. An alumina layer (26) is formed on the remaining portion of the substrate, and also on the bond coat. A ceramic layer (28) is then applied on the alumina layer. Even if the ceramic material is removed, the localized bond coat remains, and reduces the rate at which the underlying substrate oxidizes. A coated article is also disclosed, as is a system that utilizes a conventional superalloy and aluminide coating with the localized bond coat.