Design rules for the thermal and elastic properties of rare-earth disilicates

Rare-earth silicates are the current standard material for use as environmental barrier coatings SiC-based ceramic matrix composites hot-section components in gas-turbine engines. Expanding design space to all available rare-earth elements facilitate optimizing functionality requires an understanding of systematic trends RE2Si2O7 properties. In this work, we combine first-principles calculations with experimental measurements Young’s modulus, coefficient thermal expansion, and conductivity a range different compositions phases. Clear observed these properties function radius cation. case modulus also hold multi-component systems; while systems is noticeably lower, indicating potential such materials act barriers. These results provide rules developing new stiffness expansion engineered match that substrate, simultaneously having reduced conductivity.