J. Mater. Sci. Technol. ›› 2020, Vol. 52: 20-28.DOI: 10.1016/j.jmst.2020.02.051

• Research Article • Previous Articles     Next Articles

Mechanical and thermal properties of RETaO4 (RE = Yb, Lu, Sc) ceramics with monoclinic-prime phase

Lin Chena, Mingyu Hua,b, Jun Guoa, Xiaoyu Chonga,*(), Jing Fenga,*()   

  1. a Faculty of Material Science and Engineering, Kunming University of Science and Technology, Kunming 650093, People’s Republic of China
    b School of Engineering, Brown University, Providence, RI, 02912, USA
  • Received:2019-01-18 Revised:2020-02-04 Accepted:2020-02-05 Published:2020-09-15 Online:2020-09-18
  • Contact: Xiaoyu Chong,Jing Feng


As candidate thermal/environmental barrier coatings (T/EBCs), the structure characteristics and comprehensive properties of monoclinic-prime (m') RETaO4 (RE = Yb, Lu, Sc) with excellent Al2O3/SiO2 chemical compatibility are studied. Excellent thermal insulation protection will be provided by m'RETaO4 due to their low thermal conductivity (~1.6 W m -1 K -1, 900 °C) and prominent thermal radiation resistance, which is much better than those of YSZ (~2.5 W m -1 K -1, 1000 °C) and La2Zr2O7 (~2.0 W m -1 K -1, 900 °C). The thermal expansion coefficients (TECs) are 3.0-8.0 × 10 -6 K -1 (200-1200 °C), which is suitable for T/EBCs applications. Furthermore, absence of phase transition and extraordinary chemical compatibility with Al2O3/SiO2 up to 1500 °C indicate the potential application prospect. The documented governing mechanisms of m'RETaO4 properties will enable researchers to promote their application in the future investigation.

Key words: Ceramics, Thermal/environmental barrier coatings, Rare earth tantalates, Mechanical property, Thermal conductivity, Chemical compatibility