J. Mater. Sci. Technol. ›› 2020, Vol. 47: 216-222.DOI: 10.1016/j.jmst.2020.02.015

• Research Article • Previous Articles     Next Articles

Achieving strong microwave absorption capability and wide absorption bandwidth through a combination of high entropy rare earth silicide carbides/rare earth oxides

Heng Chena,b, Biao Zhaoc, Zifan Zhaoa, Huimin Xianga, Fu-Zhi Daia, Jiachen Liub, Yanchun Zhoua,b,*()   

  1. aScience and Technology on Advanced Functional Composite Laboratory, Aerospace Research Institute of Materials & Processing Technology, Beijing 100076, China
    bKey Laboratory of Advanced Ceramics and Machining Technology of Ministry of Education, School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China
    cHenan Key Laboratory of Aeronautical Materials and Application Technology, School of Material Science and Engineering, Zhengzhou University of Aeronautics, Zhengzhou 450046, China
  • Received:2020-01-20 Revised:2020-02-05 Accepted:2020-02-17 Published:2020-06-15 Online:2020-06-24
  • Contact: Yanchun Zhou

Abstract:

Developing electromagnetic (EM) wave absorbing materials with low reflection coefficient and optimal operating frequency band is urgently needed on account of the increasingly serious EM pollution. However, the applications of common EM absorbing materials are encumbered by poor high-temperature stability, poor oxidation resistance, narrow absorption bandwidth or high density. Herein, the strong EM absorption capability and wide efficient absorption bandwidth of high entropy ceramics are reported for the first time, which are designed by a combination of the novel high entropy (HE) rare earth silicide carbides/rare earth oxides (RE3Si2C2/RE2O3). Three HE powders, i.e., HERSC-1 (HE (Tm0.2Y0.2Dy0.2Gd0.2Tb0.2)3Si2C2), HERSC-2 HE (Tm0.2Y0.2Pr0.2Gd0.2Dy0.2)3Si2C2/HE (Tm0.2Y0.2Pr0.2Gd0.2Dy0.2)2O3) and HERSC-3 (HE (Tm0.2Y0.2Pr0.2Gd0.2Tb0.2)3Si2C2/HE (Tm0.2Y0.2Pr0.2Gd0.2Tb0.2)2O3), are synthesized. Although HERSC-1 exhibits a limited absorption effect (the minimum reflection loss (RLmin) is -11.6 dB at 3.4 mm) and a relatively narrow effective absorption bandwidth (EAB) of 1.7 GHz, the optimal absorption RLmin value and EAB of HERSC-2 and HERSC-3 are -40.7 dB (at 2.9 mm), 3.4 GHz and-50.9 dB (at 2.0 mm), 4.5 GHz, respectively, demonstrating strong microwave absorption capability and wide absorption bandwidth. Considering the better stability, low density and strong EM absorption effect, HE ceramics are promising as a new type of EM absorbing materials.

Key words: High entropy ceramics, Rare earth silicide carbides, Absorption materials, Reflection loss, Interfacial polarization