METHODS AND MATERIALS FOR REPAIRING A THERMAL BARRIER COATING OF A GAS TURBINE COMPONENT

• Main Authors: KULKARNI, Ambarish Jayant, SAHA, Atanu, BEWLAY, Bernard Patrick, NAGESH, Mamatha, WALLACE, Margeaux, KESHAVAN, Hrishikesh
• Format: Patent
• Language: English; French; German
• Published: 12.01.2022
• Subjects: ARTIFICIAL STONE; BLASTING; CEMENTS; CERAMICS; 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; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDINGMATERIALS; CONCRETE; DIFFUSION TREATMENT OF METALLIC MATERIAL; ENGINE PLANTS IN GENERAL; HEATING; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; LIGHTING; LIME, MAGNESIA; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; METALLURGY; NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAMTURBINES; REFRACTORIES; SLAG; STEAM ENGINES; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; TREATMENT OF NATURAL STONE; WEAPONS

A sprayable thermal barrier coating powder mixture (208) for a gas turbine engine (10) includes: a dry composition having a low surface area ceramic powder (214) having a median particle size distribution greater than 5 microns and less than 50 microns, and a high surface area ceramic powder (216) having a median particle size distribution smaller than 5 microns, wherein the low surface area ceramic powder (214) makes up at least 50% by weight of the dry composition of the sprayable thermal barrier coating powder mixture (208). The low surface area ceramic powder (214) has less than 10 meters squared of surface area per gram, and wherein the high surface area ceramic powder (216) has greater than 10 meters squared of surface area per gram and less than 4,000 meters squared of surface area per gram.A method (300) for repairing a thermal barrier coating (146) of a component (252) of a gas turbine engine (10) in situ comprising:spraying a thermal barrier coating powder mixture (208) onto the component (252) of the gas turbine engine (10) in situ, the thermal barrier coating powder mixture (208) comprising a low surface area ceramic powder (214), a low surface area ceramic powder (214) precursor, or both, the thermal barrier coating powder mixture (208) further comprising a high surface area ceramic powder (216), the thermal barrier coating powder mixture (208) defining an activation temperature range from 300 degrees Celsius to 1200 degrees Celsius; andoperating the gas turbine engine (10) to cure the thermal barrier coating powder mixture (208) on the component (252).