J. Mater. Sci. Technol. ›› 2020, Vol. 38: 80-85.DOI: 10.1016/j.jmst.2019.09.006

• Letter • Previous Articles     Next Articles

Effect of reaction routes on the porosity and permeability of porous high entropy (Y0.2Yb0.2Sm0.2Nd0.2Eu0.2)B6 for transpiration cooling

Heng Chenab, Zifan Zhaob, Huimin Xiangb, Fu-Zhi Daib, Jie Zhangc, Shaogang Wangc, Jiachen Liua, Yanchun Zhoub*()   

  1. aKey Laboratory of Advanced Ceramics and Machining Technology of Ministry of Education, School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China
    bScience and Technology on Advanced Functional Composite Laboratory, Aerospace Research Institute of Materials & Processing Technology, Beijing 100076, China
    cShenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
  • Received:2019-08-06 Revised:2019-09-09 Accepted:2019-09-09 Published:2020-02-01 Online:2020-02-10
  • Contact: Zhou Yanchun


Transpiration cooling technique is a reusable and high-efficiency thermal protection system (TPS), which is potential to improve the reusability and security of re-entry space vehicle. Relatively low density, high permeability and high porosity are general requirements for porous media of transpiration cooling systems. In this work, a new porous high entropy metal hexaboride (Y0.2Yb0.2Sm0.2Nd0.2Eu0.2)B6 is designed and prepared by the in-situ reaction/partial sintering method. Two reaction routes are designed to synthesize (Y0.2Yb0.2Sm0.2Nd0.2Eu0.2)B6, including boron thermal reduction and borocarbon thermal reduction. The as-prepared porous HE (Y0.2Yb0.2Sm0.2Nd0.2Eu0.2)B6 ceramics possess homogeneous microstructure and exhibit low density, high porosity, high compressive strength and high permeability. The combination of these properties makes porous HE (Y0.2Yb0.2Sm0.2Nd0.2Eu0.2)B6 promising as a candidate porous media for various transpiration cooling applications.

Key words: High entropy ceramics, (Y0.2Yb0.2Sm0.2Nd0.2Eu0.2)B6, Transpiration cooling, Porous UHTCs, In-situ reaction synthesis