Thermophysical properties of rare earth barium aluminates |
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| Authors: | Jing Feng Yunxuan Zhou Xiaorui Ren Peng Song Wei Pan |
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| Affiliation: | 1. Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, China;2. Department of Materials Science and Engineering, Tsinghua University, Beijing, China |
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| Abstract: | The super low thermal conductivity and ultrahigh thermal expansion of Ba6Ln2Al4O15 (Ln = Gd, Dy, Er, and Yb) compounds with one‐sixth of the oxygen vacancy have been synthesized by the solid‐state reaction method. The lowest thermal conductivity of Ba6Yb2Al4O15 was found to be 0.98 W/(m.K) at 1073 K. The large concentration of oxygen vacancies in Ba6Ln2Al4O15 compounds leads to low elastic modulus and loose chemical bonds. The average thermal expansion coefficients of Ba6Ln2Al4O15 compounds was 11.8 × 10?6 ? 13.6 × 10?6 · K?1. The loose chemical bonds with Young's moduli were in the range of 102.8 ? 135.9 GPa. |
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| Keywords: | Ba6Ln2Al4O15 compounds ceramic thermal conductivity thermal expansion coefficients |
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