TY - JOUR
T1 - In-situ phase evolution of multi-component boride to high-entropy ceramic upon ultra-high temperature ablation
AU - Guo, Lingxiang
AU - Wang, Yuqi
AU - Liu, Bing
AU - Zhang, Yuyu
AU - Tang, Ying
AU - Li, Hongbin
AU - Sun, Jia
N1 - Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2023/4
Y1 - 2023/4
N2 - Multi-component boride (Hf0.5Zr0.5)B2-SmB6-ErB4-YB6 (HZRB) utilized as a coating on SiC-coated carbon/carbon (C/C) composite was prepared by supersonic atmosphere plasma spraying. In-situ phase evolution of HZRB into (Hf0.2Zr0.2Sm0.2Er0.2Y0.2)O2-δ high-entropy oxide (HEO) was investigated after oxyacetylene ablation for 120 s. The first-principles calculations were applied to analyze the in-situ formation mechanism of HEO. The mixing Gibbs free energy change (∆Gmix) of HEO was calculated to be negative at 2573 K, indicating that the HEO can be generated upon the ablation temperature. Due to the lower Gibbs free energy change of reaction (∆RGm), (Hf0.5Zr0.5)B2 will be oxidized to generate HfO2 firstly, and other elements dissolved into the HfO2 lattice to form HEO. The solution energies of Zr, Sm, Er and Y atoms are − 0.01, 6.28, 8.55 and 4.46 eV/atom, and corresponding solution reactions possess negative ∆RGm, indicating the possible solution sequence of these elements is Zr > Y > Sm > Er.
AB - Multi-component boride (Hf0.5Zr0.5)B2-SmB6-ErB4-YB6 (HZRB) utilized as a coating on SiC-coated carbon/carbon (C/C) composite was prepared by supersonic atmosphere plasma spraying. In-situ phase evolution of HZRB into (Hf0.2Zr0.2Sm0.2Er0.2Y0.2)O2-δ high-entropy oxide (HEO) was investigated after oxyacetylene ablation for 120 s. The first-principles calculations were applied to analyze the in-situ formation mechanism of HEO. The mixing Gibbs free energy change (∆Gmix) of HEO was calculated to be negative at 2573 K, indicating that the HEO can be generated upon the ablation temperature. Due to the lower Gibbs free energy change of reaction (∆RGm), (Hf0.5Zr0.5)B2 will be oxidized to generate HfO2 firstly, and other elements dissolved into the HfO2 lattice to form HEO. The solution energies of Zr, Sm, Er and Y atoms are − 0.01, 6.28, 8.55 and 4.46 eV/atom, and corresponding solution reactions possess negative ∆RGm, indicating the possible solution sequence of these elements is Zr > Y > Sm > Er.
KW - Ablation
KW - First-principles calculations
KW - High-entropy ceramics
KW - Rare earth borides
KW - Ultra-high temperature ceramics
UR - http://www.scopus.com/inward/record.url?scp=85142830656&partnerID=8YFLogxK
U2 - 10.1016/j.jeurceramsoc.2022.11.019
DO - 10.1016/j.jeurceramsoc.2022.11.019
M3 - 文章
AN - SCOPUS:85142830656
SN - 0955-2219
VL - 43
SP - 1322
EP - 1333
JO - Journal of the European Ceramic Society
JF - Journal of the European Ceramic Society
IS - 4
ER -