TY - JOUR
T1 - An entropy-stabilized disilicate for advanced T/EBC
T2 - Synergistic thermal and corrosion resistance
AU - Wang, Xu
AU - Fang, Shige
AU - Xu, Feihan
AU - Liu, Ling
AU - Ma, Zhuang
N1 - Publisher Copyright:
© 2025 The American Ceramic Society.
PY - 2026/1
Y1 - 2026/1
N2 - A low thermal conductivity, compatible thermal expansion coefficient, and excellent resistance to calcium–magnesium–aluminum–silicate (CMAS) corrosion are critical requirements for thermal/environmental barrier coatings (T/EBC) applied to silicon-based ceramics. Rare earth disilicates are considered among the most promising ecological barrier coating materials due to their superior resistance to water vapor corrosion. However, the relatively high thermal conductivity and poor resistance to CMAS corrosion limit the practical application. In this work, a single-phase high-entropy rare earth disilicate (Lu1/5Yb1/5Sc1/5Er1/5Y1/5)2Si2O7((5RE1/5)2Si2O7) was successfully synthesized via a solid-state reaction. It exhibits a low thermal conductivity of 1.92 W⋅m−1⋅K −1 at 1273 K, a thermal expansion coefficient (4.89 × 10−6/°C) matching that of SiCf/SiC ((4.5–5.5) ×10−6/°C), high hardness and elastic modulus (11.22 and 184.6 GPa, respectively, at 25°C), and exceptional CMAS corrosion resistance, forming a reaction layer of only 28 µm after 48 h at 1300°C. The enhanced comprehensive performance is attributed to the synergistic combination of multiple rare-earth cations with different ionic radii within the high-entropy structure, highlighting its great promise as a next-generation T/EBC material.
AB - A low thermal conductivity, compatible thermal expansion coefficient, and excellent resistance to calcium–magnesium–aluminum–silicate (CMAS) corrosion are critical requirements for thermal/environmental barrier coatings (T/EBC) applied to silicon-based ceramics. Rare earth disilicates are considered among the most promising ecological barrier coating materials due to their superior resistance to water vapor corrosion. However, the relatively high thermal conductivity and poor resistance to CMAS corrosion limit the practical application. In this work, a single-phase high-entropy rare earth disilicate (Lu1/5Yb1/5Sc1/5Er1/5Y1/5)2Si2O7((5RE1/5)2Si2O7) was successfully synthesized via a solid-state reaction. It exhibits a low thermal conductivity of 1.92 W⋅m−1⋅K −1 at 1273 K, a thermal expansion coefficient (4.89 × 10−6/°C) matching that of SiCf/SiC ((4.5–5.5) ×10−6/°C), high hardness and elastic modulus (11.22 and 184.6 GPa, respectively, at 25°C), and exceptional CMAS corrosion resistance, forming a reaction layer of only 28 µm after 48 h at 1300°C. The enhanced comprehensive performance is attributed to the synergistic combination of multiple rare-earth cations with different ionic radii within the high-entropy structure, highlighting its great promise as a next-generation T/EBC material.
KW - (LuYbScErY)SiO
KW - CMAS corrosion
KW - high-entropy rare earth disilicate
KW - high-temperature thermal properties
UR - https://www.scopus.com/pages/publications/105024539378
U2 - 10.1111/jace.70426
DO - 10.1111/jace.70426
M3 - Article
AN - SCOPUS:105024539378
SN - 0002-7820
VL - 109
JO - Journal of the American Ceramic Society
JF - Journal of the American Ceramic Society
IS - 1
M1 - e70426
ER -