Degradation mechanisms and design strategies in environmental barrier coatings: A review

Abstract Environmental barrier coatings (EBCs) mitigate the degradation of ceramic matrix composites in harsh environments caused by high‐temperature water vapor, molten salts, and corrosive gases, thereby extending component lifespan. This review provides a comprehensive analysis of the degradation mechanisms governing EBC failure, including oxidation, volatilization, calcium‒magnesium‒aluminosilicate attack, steam corrosion, and thermal shock. To establish a foundation, it first outlines EBC materials, processing techniques, and key performance metrics. A detailed examination of phase stability, thermal and chemical compatibility, fracture resistance, and microstructural evolution under service conditions is presented. The influence of deposition methods, coating architecture, and interface design on degradation resistance is highlighted, emphasizing the roles of thermally grown oxides, rare‐earth silicates, and multilayer systems. Recent advancements—such as nanostructured coatings, self‐healing architectures, and high‐entropy ceramics—are also discussed. This review synthesizes current knowledge into a coherent conceptual framework to guide the design and application of next‐generation EBCs.