Renewing a thermal barrier coating system

• Main Authors: WORTMAN, DAVID JOHN, RIGNEY, JOSEPH DAVID, CONNER, JEFFREY ALLEN, NAGARAJ, BANGALORE ASWATHA
• Format: Patent
• Language: English; French; German
• Published: 10.01.2007
• Subjects: 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; DIFFUSION TREATMENT OF METALLIC MATERIAL; ENGINE PLANTS IN GENERAL; HEATING; 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 (TBC) system, comprising a metallic bond coat on an article surface (14) and an outer ceramic TBC is repaired by renewing without removing the bond coat. The outer ceramic TBC is removed to expose a bond coat substrate. At least one discrete local surface area (16,18) of the article surface (14) subject to bond coat degradation is selected from a thermal pattern unique to the article surface from service operation. At least one renewal metal selected from Pt, Rh, and Pd is applied at least to the selected discrete local surface area (16,18) and heated to diffuse the renewal metal into the bond coat substrate. An environmental resistant coating selected from aluminides and alloys including aluminum is applied at least to the discrete local surface area (16,18) over the renewal metal. Thereafter, an outer ceramic TBC is applied to the article surface (14).