Design, Preparation and Thermal Properties of (La_0.4Sm_0.5Yb_0.1)₂Zr₂O₇ Ceramic for Thermal Barrier Coatings

Abstract:

According to the theory of phonon transport and thermal expansion, a new complex rare-earth zirconate ceramic (La0.4Sm0.5Yb0.1)2Zr2O7, with low thermal conductivity and high thermal expansion coefficient, has been designed by doping proper ions at A sites. The complex rare-earth zirconate (La_0.4Sm_0.5Yb_0.1)₂Zr₂O₇ powder for thermal barrier coatings (TBCs) was synthesized by coprecipitation-calcination method. The phase, microstructure and thermal properties of the new material were investigated. The results revealed that single phase (La_0.4Sm_0.5Yb_0.1)₂Zr₂O₇ with pyrochlore structure was synthesized. The thermal conductivity and the thermal expansion coefficient of the designed complex rare-earth zirconate ceramic is about 1.3W/m•K and 10.5×10^-6/K, respectively. These results imply that (La_0.4Sm_0.5Yb_0.1)₂Zr₂O₇ can be explored as the candidate material for the ceramic layer in TBCs system.

• Periodical: Key Engineering Materials (Volumes 512-515)
• Pages: 469-473
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.512-515.469
• Online since: June 2012
• Authors: L. Liu, Z. Ma, F.C. Wang, Q. Xu
• Keywords: Complex Rare-Earth Zirconate, Thermal Barrier Coating (TBC), Thermal Property

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