Coating structure and surface treating method

Abstract

Disclosed are a coating structure and a surface treating method. The coating structure comprises a high-temperature component (2). An intermediate layer (3) formed of a glass-containing oxide ceramic is provided by thermal spraying on the surface of a part of the high-temperature component (2). An environmentally resistant film (4) formed of a coating material, which has heat resistance and resistance to a thickness reduction upon exposure to steam, is provided on the surface of the intermediate layer (3). The oxide ceramic comprises a plurality of oxide ceramics that do not undergo a change in crystal phase in a temperature range of a room temperature to 1400 DEG C or can maintain an identical volume even if the crystal phase changes. The coefficient of thermal expansion of the plurality of oxide ceramics is intermediate between the coefficient of thermal expansion of an SiC ceramic-based composite material constituting the high-temperature component (2) and the coefficient of thermal expansion of the coating material constituting the environmentally resistant film (4).

Description

Technical field [0001] The present invention relates to a coating structure and a surface treatment method for ensuring the heat resistance and water vapor corrosion resistance of at least a part of high temperature components such as gas turbine components. Background technique [0002] In recent years, as a material for high-temperature parts such as gas turbine parts used in high-temperature gas environments containing water vapor, it is noteworthy that the use of SiC series, which has better heat resistance than nickel alloys, and has a smaller specific gravity Ceramic Matrix Composite (CMC). On the other hand, it has been found that water vapor in a high-temperature gas will cause a corrosion reaction of Si-containing materials. When SiC series ceramic matrix composite materials are used as the material of high-temperature parts, it is necessary to ensure heat resistance for at least a part of the high-temperature parts -Water vapor corrosion resistance. In addition, in or...

AI Technical Summary

Problems solved by technology

Therefore, when high-temperature components are used in a high-temperature gas environment above 900°C, the intermediate layer is prone to cracking and peeling, and it is difficult to ensure the heat resistance and water vapor corrosion resistance of high-temperature components for a long time

That is, in addition to improving the construction of the coating structure, in other words, improving the ease and reliability of the construction of the surface treatment, it is difficult to ensure the heat resistance-water resistance of high-temperature components used in high-temperature gas environments above 900°C for a long period of time. Vapor Corrosivity Problems

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