Keynote Speaker

Prof. Yi Zeng (Research Fellow)

Shanghai Institute of Ceramics, Chinese Academy of Sciences

E-mail: zengyi@mail.sic.ac.cn

Title: Investigation on the Relationship Between CMAS Corrosion Mechanism and Microstructure of Multicomponent Monosilicates

Profile:

Zeng Yi, full professor in Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS), serves as the Director of the Testing Center at SICCAS and Director of the Advanced Inorganic Materials Science and Engineering Industrial Technology Foundation Public Platform under the Ministry of Industry and Information Technology (MIIT). His research work focuses on the microstructure characterization of coating materials. He is the Chief Scientist of the National Key R&D Program’s Instrument Development Project and has led multiple national and regional research initiatives, including projects under the National Key R&D Program’s Materials Genome Initiative, the National 863 Program, international cooperation projects supported by the Ministry of Science and Technology, and the Shanghai Municipal Science and Technology Support Program. He has published over 100 SCI-indexed papers as the first author or corresponding author. Additionally, he holds key positions in academic and professional organizations, including Deputy Director of the Scanning Electron Microscopy Committee of the Chinese Society for Electron Microscopy, Vice Chairman of the Shanghai Society for Microscopy, and Chairman of the National Subcommittee on Coating Characterization Standardization.

Abstract:

Understanding corrosion mechanisms and enhancing material corrosion resistance are of significant importance for reducing global corrosion costs. However, uncertainties regarding the primary mechanisms of CMAS corrosion in extreme environments have limited the enhancement of anti-CMAS corrosion performance in monosilicates through mixing and matching critical rare earth components. In this report, we propose a methodology utilizing correlated electron microscopy techniques combined with theoretical calculations to elucidate the competing mechanisms governing CMAS corrosion in monosilicates. Our findings reveal a temperature-dependent competition between thermodynamics and kinetics during corrosion. Based on this, we developed novel multicomponent monosilicates that exhibit exceptional corrosion resistance even at 1,500 ℃. This achievement was realized through precise regulation of rare earth ion radii in monosilicates to establish a delicate balance between thermodynamic and kinetic competition. After 50-hour and 100-hour corrosion tests, the thinnest reaction layers measured were merely 28.8 μm and 35.4 μm, respectively. Furthermore, we proposed a descriptor for evaluating the solid solubility of multicomponent rare earth monosilicates. Based on this descriptor and corrosion assessment results from over twenty monosilicates, we established composition design guidelines for multicomponent monosilicates capable of predicting optimal rare earth compositions for superior corrosion resistance at different operating temperatures. These findings provide crucial theoretical support for accelerating the development of multicomponent rare earth monosilicates, enabling customized compositions with outstanding anti-corrosion performance under specific service temperatures.