Theoretical and experimental determination of the major thermo-mechanical properties of RE₂SiO₅ (RE = Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y) for environmental and thermal barrier coating applications

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• 作者：Zhilin Tian^a ; ^b ; Liya Zheng^a ; ^b ; Jiemin Wang^a ; Peng Wan^a ; ^b ; Jialin Li^a ; Jingyang Wang^a ; ^{jywang@imr.ac.cn" class="auth_mail" title="E-mail the corresponding author}
• 关键词：Rare-earth silicates ; Environmental barrier coating ; Mechanical property ; Thermal property
• 刊名：Journal of the European Ceramic Society
• 出版年：2016
• 出版时间：January 2016
• 年：2016
• 卷：36
• 期：1
• 页码：189-202
• 全文大小：4361 K

文摘

X2-RE₂SiO₅ orthosilicates are promising candidate environmental/thermal barrier coating (ETBC) materials for silicon-based ceramics because of their excellent durability in high-temperature environments and potential low thermal conductivities. We herein present the mechanical and thermal properties of X2-RE₂SiO₅ orthosilicates based on theoretical explorations of their elastic stiffness and thermal conductivity, and experimental evaluations of the macroscopic performances of dense specimens from room to high temperatures. Mechanical and thermal properties may be grouped into two: those that are sensitive to the rare-earth (RE) species, including flexural strength, elastic modulus, and thermal shock resistance, and those that are less sensitive to the RE species, including thermal conductivity, thermal expansion coefficient, and brittle-to-ductile transition temperature (BDTT). The orthosilicates show excellent elastic stiffness at high temperatures, high BDTTs, very low experimental thermal conductivities, and compatible thermal expansion coefficients. The reported information provides important material selection and optimization guidelines for X2-RE₂SiO₅ as ETBC candidates.