Affiliation:
1. Key Laboratory of Inorganic Coating Materials CAS, Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai China
2. College of Materials Science and Engineering Nanjing Tech University Nanjing China
3. Guizhou Aerospace Fenghua Precision Equipment Co., Ltd Guiyang China
Abstract
AbstractRare‐earth (RE) silicates environmental barrier coatings (EBCs) are prone to accelerate failure resulted from molten calcium–magnesium–aluminum silicate (CMAS), which presents significant challenges to the design and development of durable EBCs. In this study, X1‐Gd2SiO5 and X2‐Er2SiO5 coatings were explored on their corrosion resistance to CMAS melts with different Ca/Si ratios (1.1, 0.75, 0.64, and 0.42) at 1350°C for 25 and 50 h, respectively. Results showed that with the Ca/Si ratio increasing, CMAS viscosity decreased and a more intense corrosion reaction with coatings occurred. Garnet phase was only observed in X2‐Er2SiO5 coating corroded by CMAS with high Ca/Si ratios, which could be beneficial for improving corrosion resistance. The X2‐Er2SiO5 phase, which is composed of [SO4] and [REO6]/[REO7] polyhedrons, exhibits better corrosion resistance due to its more stable crystal structure, lower reactivity with CMAS, and the radius difference between the RE ions and Ca2+.
Funder
National Natural Science Foundation of China
National Key Research and Development Program of China