Materials scientists have long sought to enhance the durability of thermal/environmental barrier coatings (T/EBCs) under extreme conditions, particularly against corrosion caused by calcium‑magnesium‑alumino‑silicate (CMAS) melts. Understanding the corrosion mechanisms and accurately predicting the long‑term service life of coating materials remain critical challenges for aerospace and energy applications.
Recently, a research team from Harbin Institute of Technology and Shanghai University achieved a significant breakthrough. They designed two novel high‑entropy rare‑earth disilicates—(Er1/4Y1/4Lu1/4Yb1/4)2Si2O7 and (Er1/6Tm1/6Y1/15Gd1/15Lu4/15Yb4/15)2Si2O7—which exhibit outstanding CMAS corrosion resistance. More importantly, the team revealed the underlying corrosion mechanisms and developed a physics‑informed prediction model that enables highly accurate forecasting of long‑term corrosion behavior.
The team published their work in Journal of Advanced Ceramics on January 15, 2026.
"Our designed high‑entropy disilicates reduce the CMAS corrosion depth by approximately 70% compared with traditional single‑component rare‑earth disilicates, demonstrating exceptional corrosion resistance," said Prof. Yuelei Bai, a corresponding author of the study and a professor at Harbin Institute of Technology specializing in thermal protection materials and systems. "But beyond performance improvement, we aimed to uncover why these materials perform so well and how we can predict their behavior over extended service periods."
The study systematically investigated the corrosion mechanisms under different temperatures. At 1300 °C, the corrosion process is dominated by thermodynamics–kinetics competition, whereas at 1500 °C it shifts to a dissolution–reprecipitation mechanism. "We found that the lattice distortion induced by multi‑cation doping effectively suppresses the penetration of CMAS melt, while larger‑radius rare‑earth ions consume Ca²⁺ in the melt, thereby reducing its corrosivity," explained Prof. Bin Liu, a corresponding author from Shanghai University who focuses on material design and multiscale simulation. "This mechanistic understanding provides clear guidance for designing next‑generation corrosion‑resistant coatings."
To address the long‑standing challenge of predicting long‑term corrosion evolution, the team developed an extended Kalman filter model that integrates physical corrosion mechanisms. "Traditional prediction methods often lack accuracy over extended periods. Our model continuously assimilates data and self‑corrects, achieving a prediction error of less than 3% for corrosion depth and rate at 1300 °C," noted Prof. Bai. "This provides a reliable tool for coating lifetime assessment and maintenance planning."
The research not only advances the fundamental understanding of CMAS corrosion in high‑entropy ceramics but also establishes a robust framework for predictive lifetime management. "We are now working to expand the model to more complex service environments and to guide the design of other high‑entropy coating systems," Prof. Liu added. "The ultimate goal is to enable safer, longer‑lasting protective coatings for high‑temperature applications."
Other contributors include Yun Fan, Xiaodong He, Dong Chen, Zhaoxu Sun and collaborators from Harbin Institute of Technology and Shanghai University.This work is supported by the National Natural Science Foundation of China (No. U21A2063, 52172071 and 51972080) and Shanghai Technical Service Center for Advanced Ceramics Structure Design and Precision Manufacturing (NO. 20DZ2294000).
About Author
Yuelei Bai is a professor in mechanics at the Center for Composite Materials and Structures, School of Astronautics, Harbin Institute of Technology. In 2013, he received funding from the first batch of the Postdoctoral International Exchange Program (sponsored by the National Postdoctoral Management Committee under the Ministry of Human Resources and Social Security) and then conducted two years of postdoctoral research at Imperial College London and Nanyang Technological University in Singapore. Currently, his research primarily focuses on both basic and applied research in the fields of ternary layered ceramics, multi-scale simulations of material behavior in extreme environments, ceramic-matrix composites, and thermal protection materials and systems. He is dedicated to addressing scientific and technological challenges in aerospace, aviation, transportation, and other sectors. In recent years, he has published 56 academic papers in top-tier international journals, such as Acta Materialia and the Journal of the American Ceramic Society. These papers have been cited 1,958 times, and his H-index is 26. He also serves as an Associate Editor for the Journal of the American Ceramic Society and is a member of the editorial board of Journal of Advanced Ceramics.
Bin Liu is a Professor and Doctoral Supervisor at Shanghai University. His research primarily involves the regulation of "composition-structure-chemical bond" in novel ceramics, the constitutive relationships in new material design, and studies on multi-scale defects and their relationship with properties. He has published over 170 SCI journal papers, cited more than 5900 times in SCI articles, and applied for/been granted 13 patents. He has been invited to organize/co-organize 13 computational sessions at domestic and international conferences and has given 21 invited talks at conferences hosted by organizations like the American Ceramic Society. He serves as an Associate Editor for J. Am. Ceram. Soc., and is on the editorial boards of J. Mater. Sci. Technol. and J. Adv. Ceram..
About Journal of Advanced Ceramics
Journal of Advanced Ceramics (JAC) is an international academic journal that presents the state-of-the-art results of theoretical and experimental studies on the processing, structure, and properties of advanced ceramics and ceramic-based composites. JAC is Fully Open Access, monthly published by Tsinghua University Press, and exclusively available via SciOpen . JAC's 2024 IF is 16.6, ranking in Top 1 (1/33, Q1) among all journals in "Materials Science, Ceramics" category, and its 2024 CiteScore is 25.9 (5/130) in Scopus database. ResearchGate homepage: https://www.researchgate.net/journal/Journal-of-Advanced-Ceramics-2227-8508
