Coating coating is one of the high temperature protective coatings, and aerospace engines are its important downstream

Coating coating is a coating formed by depositing coating materials directly on the surface of an alloy substrate using physical or chemical methods. The coating material is usually a metal or alloy that is resistant to high temperatures, oxidation, and corrosion. After deposition, it will interact with the alloy substrate. Tightly combined, the main function is to protect. Coating coatings are mainly used in the aerospace industry to improve the high-temperature corrosion resistance and high-temperature oxidation resistance of hot-end components of aerospace engines such as turbine blades and combustion chambers, thereby extending the service life of aerospace engines.

The hot-end components of aerospace engines generally use high-temperature alloys. Due to long-term operation in high-temperature water vapor environments, high-temperature alloys need to have both high-temperature mechanical stability and high-temperature corrosion resistance, and it is difficult to optimize these two properties at the same time. Aircraft manufacturing technology is constantly improving, the thrust-to-weight ratio of aero engines is increasing, the working environment temperature of hot-end components is increasing, and the performance of high-temperature alloys is increasingly unable to meet the requirements. In this context, high-temperature protective coatings are indispensable. As a type of high-temperature protective coatings, coating coatings have broad room for development.

According to the “Coating Coating Industry In-depth Market Research and Investment Strategy Suggestions Report 2022-2026” released by the Industrial Research Center, The coating will interact with the base material during deposition, thereby improving the bonding force between the coating and the base. The base material does not participate in the formation of the coating, and the coating and the base do not restrict each other. Therefore, the coating is in the material. The selection is more diverse, and deposition technology can be used to optimize the high temperature resistance, corrosion resistance and other properties of the coating to extend its service life. Common coating coatings mainly include metal coatings and ceramic coatings. At present, MCrAlY coating coating is the most representative.

Metal elements that can be used in MCrAlY coating include but are not limited to iron, aluminum, nickel, chromium, cobalt, zirconium, hafnium, tantalum, rhenium, niobium, etc. Different combinations of metal elements can produce different effects, such as nickel-chromium- Aluminum has excellent oxidation resistance, and cobalt-chromium-aluminum has excellent corrosion resistance. Therefore, MCrAlY coatings with different properties can be prepared by adjusting the composition to meet the needs of hot-end components in different working environments and different alloy materials.

The coating coating preparation processes mainly include electron beam physical vapor deposition (EB-PVD), plasma spraying (APS), vacuum coating, sputter coating, ion coating, supersonic flame spraying, etc. Among them, electron beam physical vapor deposition and plasma spraying are the mainstream preparation methods of coating coatings. In comparison, the coating coating prepared by electron beam physical vapor deposition has better comprehensive performance, but the cost is also higher.

Industry analysts said that the United States has advanced technology in MCrAlY coating coatings and uses more of it on military aircraft engine turbine blades. It is a cobalt-chromium-aluminum coating with excellent corrosion resistance. With the continuous advancement of technology, thermal barrier coatings, environmental barrier coatings, etc. have been developed and developed. Especially with the large weight ratio and lightweight development of aircraft, the application proportion of silicon carbide ceramic matrix composites continues to rise, and the environmental barrier coating market More space. From this point of view, coating coatings need to continuously improve their core competitiveness.