Journal of Inorganic Materials ›› 2022, Vol. 37 ›› Issue (12): 1289-1294.DOI: 10.15541/jim20220320

Special Issue: 【结构材料】高熵陶瓷(202409)

• RESEARCH ARTICLE • Previous Articles     Next Articles

High Entropy Oxide Ceramics (MgCoNiCuZn)O: Flash Sintering Synthesis and Properties

LI Wangguo1(), LIU Dianguang1(), WANG Kewei2, MA Baisheng2, LIU Jinling3   

  1. 1. School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, China
    2. School of Mechanical Engineering, Dongguan University of Technology, Dongguan 523808, China
    3. School of Mechanics and Aerospace Engineering, Southwest Jiaotong University, Chengdu 610031, China
  • Received:2022-06-07 Revised:2022-08-09 Published:2022-12-20 Online:2022-08-26
  • Contact: LIU Dianguang, associate professor. E-mail: dianguang@swjtu.edu.cn
  • About author:LI Wangguo (1997-), male, Master candidate. E-mail: 1648155341@qq.com
  • Supported by:
    National Natural Science Foundation of China(51732009);Fundamental Research Funds for the Central Universities(2682022ZTPY076)

Abstract:

Flash sintering is a sintering technology coupled with temperature field and electric field, with characteristics of rapid mass transfer at low temperature, showing significant advantages in the synthesis of high entropy ceramics. In this study, relatively dense high entropy oxide ceramic (MgCoNiCuZn)O was synthesized by flash sintering, which properties were compared with those of conventional sintered samples. Under flash sintering condition of room temperature, the electric field intensity of 50 V/cm and the current density of 300 mA/mm2, the time of phase transformation is only 10 s. The maximum relative density of flash sintered sample is 94%, which is 22.8% higher than that of conventional sintered sample. The maximum hardness of flash sintered sample is 5.05 GPa, which is 3.95 GPa higher than that of conventional sintered sample. When the frequency is lower than 2 Hz, the dielectric constant of flash sintering sample is one order of magnitude higher than that of conventional sintered sample. The property improvement of flash sintered samples is attributed to the acceleration of mass transfer by the critical electric field to increase the material density, and the extra defects introduced by the critical electric field.

Key words: high entropy oxide ceramics, flash sintering, phase transformation, dielectric constant

CLC Number: