Thermal barrier coating system with localized deposition of a bond coat

• Main Authors: ULION, NICHOLAS E, BOSE, SUDHANGSU, GUPTA, DINESH K, MARCIN, JEANINE T
• Format: Patent
• Language: English; French; German
• Published: 05.01.2000
• Edition: 7
• Subjects: AIR INTAKES FOR JET-PROPULSION PLANTS; BLASTING; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; COMBUSTION ENGINES; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS; DIFFUSION TREATMENT OF METALLIC MATERIAL; ENGINE PLANTS IN GENERAL; GAS-TURBINE PLANTS; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; LIGHTING; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; METALLURGY; NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAMTURBINES; STEAM ENGINES; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; WEAPONS

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.