RESEARCH PROGRESS OF LOW-DIFFUSION TEMPERATURE PROTECTIVE COATINGS

With the development of the aerospace and energy fields, higher requirements are put forward for the oxidation and corrosion resistance of metal materials in high-temperature environments. In this paper, the research progress of low-diffusion high-temperature protective coatings is summarized, focusing on the challenges faced by traditional high-temperature protective coatings, such as coating failure, corrosion, and elemental interdiffusion, are discussed. The types, characteristics, and applications of high-temperature protective coatings, such as diffusion coatings, overlay coatings, thermal barrier coatings, and environmental barrier coatings, are introduced. The effects of interdiffusion on the oxidation resistance, thermal stability and mechanical properties of the coating were analyzed. It was shown that the interdiffusion caused the composition change of the coating, the decrease of the oxidation resistance and the crack growth of the substrate. Nanocrystalline coating, equilibrium coating (EQ coating) and diffusion barrier coating are proposed to solve the problem of mutual diffusion. Finally, the future research direction of low-diffusion high-temperature protective coatings is envisioned, focusing on optimizing fabrication processes, conducting in-depth studies of the coating properties, and paying attention to the long-term stability and reliability of the coatings.