A Comprehensive Analysis of CMAS Characterization, Corrosion Scenarios, and Protective Measures

Abstract

Aero engines face significant corrosion risks from environmental sediments like volcanic ash, industrial smoke, automobile exhaust, and PM2.5 during high-altitude flights. These deposits, composed of CaO-MgO-Al₂O₃-SiO₂ (CMAS), have a melting point of 1230°C, substantially lower than the operating temperature of aero engines. However, advanced thermal barrier coatings (TBCs) have demonstrated effective resistance against CMAS-induced corrosion. This paper reviews the literature extensively, systematically reviews the composition of CMAS, its corrosion mechanism and protection strategies, focuses on the analysis of the corrosion mechanism of CMAS in different environments, and finds that the atmospheric corrosion mechanism is different from that of the ocean, which provides help for the improvement of TBCs, and provides suggestions and future research directions for the development of advanced aero engines.