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Journal of Advanced Ceramics 2021, 10(3): 385-441 https://doi.org/10.1007/s40145-021-0477-y
Review | Open Access | Issue | Published: 16 April 2021

High-entropy ceramics: Present status, challenges, and a look forward

Show Author's Information Huimin XIANGa,  Yan XINGb,  Fu-zhi DAIa,  Hongjie WANGc,  Lei SUc,  Lei MIAOd,  Guojun ZHANGe,  Yiguang WANGf,  Xiwei QIg,  Lei YAOh,  Hailong WANGi,  Biao ZHAOj,  Jianqiang LIk,  Yanchun ZHOUa( )
Science and Technology on Advanced Functional Composite Laboratory, Aerospace Research Institute of Materials & Processing Technology, Beijing 100076, China
New Energy Technology Engineering Laboratory of Jiangsu Province, Nanjing University of Posts and Telecommunications, Nanjing 210023, China
State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an 710049, China
Guangxi Key Laboratory of Information Materials, Guangxi Collaborative Innovation Center of Structure and Property for New Energy and Material, School of Material Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, China
Institute of Functional Material, College of Material Science and Engineering, Donghua University, Shanghai 201620, China
Institute of Advanced Structure Technology, Beijing Institute of Technology, Beijing 100081, China
College of Metallurgy and Energy, North China University of Science and Technology, Tangshan 063210, China
College of Material Science and Engineering, Shenzhen University, Shenzhen 518060, China
School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, China
Henan Key Laboratory of Aeronautical Materials and Application Technology, School of Material Science and Engineering, Zhengzhou University of Aeronautics, Zhengzhou 450046, China
National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, CAS Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
Keywords:
high-entropy ceramics (HECs), properties, processing, structure, applications
Cite this article:
XIANG H, XING Y, DAI F-z, et al. High-entropy ceramics: Present status, challenges, and a look forward. Journal of Advanced Ceramics, 2021, 10(3): 385-441. https://doi.org/10.1007/s40145-021-0477-y
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Abstract Full text About this article

High-entropy ceramics (HECs) are solid solutions of inorganic compounds with one or more Wyckoff sites shared by equal or near-equal atomic ratios of multi-principal elements. Although in the infant stage, the emerging of this new family of materials has brought new opportunities for material design and property tailoring. Distinct from metals, the diversity in crystal structure and electronic structure of ceramics provides huge space for properties tuning through band structure engineering and phonon engineering. Aside from strengthening, hardening, and low thermal conductivity that have already been found in high-entropy alloys, new properties like colossal dielectric constant, super ionic conductivity, severe anisotropic thermal expansion coefficient, strong electromagnetic wave absorption, etc., have been discovered in HECs. As a response to the rapid development in this nascent field, this article gives a comprehensive review on the structure features, theoretical methods for stability and property prediction, processing routes, novel properties, and prospective applications of HECs. The challenges on processing, characterization, and property predictions are also emphasized. Finally, future directions for new material exploration, novel processing, fundamental understanding, in-depth characterization, and database assessments are given.


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About this article

High-entropy ceramics: Present status, challenges, and a look forward

Show Author's information Huimin XIANGa, Yan XINGb, Fu-zhi DAIa, Hongjie WANGc, Lei SUc, Lei MIAOd, Guojun ZHANGe, Yiguang WANGf, Xiwei QIg, Lei YAOh, Hailong WANGi, Biao ZHAOj, Jianqiang LIk, Yanchun ZHOUa( )
Science and Technology on Advanced Functional Composite Laboratory, Aerospace Research Institute of Materials & Processing Technology, Beijing 100076, China
New Energy Technology Engineering Laboratory of Jiangsu Province, Nanjing University of Posts and Telecommunications, Nanjing 210023, China
State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an 710049, China
Guangxi Key Laboratory of Information Materials, Guangxi Collaborative Innovation Center of Structure and Property for New Energy and Material, School of Material Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, China
Institute of Functional Material, College of Material Science and Engineering, Donghua University, Shanghai 201620, China
Institute of Advanced Structure Technology, Beijing Institute of Technology, Beijing 100081, China
College of Metallurgy and Energy, North China University of Science and Technology, Tangshan 063210, China
College of Material Science and Engineering, Shenzhen University, Shenzhen 518060, China
School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, China
Henan Key Laboratory of Aeronautical Materials and Application Technology, School of Material Science and Engineering, Zhengzhou University of Aeronautics, Zhengzhou 450046, China
National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, CAS Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China

Abstract

High-entropy ceramics (HECs) are solid solutions of inorganic compounds with one or more Wyckoff sites shared by equal or near-equal atomic ratios of multi-principal elements. Although in the infant stage, the emerging of this new family of materials has brought new opportunities for material design and property tailoring. Distinct from metals, the diversity in crystal structure and electronic structure of ceramics provides huge space for properties tuning through band structure engineering and phonon engineering. Aside from strengthening, hardening, and low thermal conductivity that have already been found in high-entropy alloys, new properties like colossal dielectric constant, super ionic conductivity, severe anisotropic thermal expansion coefficient, strong electromagnetic wave absorption, etc., have been discovered in HECs. As a response to the rapid development in this nascent field, this article gives a comprehensive review on the structure features, theoretical methods for stability and property prediction, processing routes, novel properties, and prospective applications of HECs. The challenges on processing, characterization, and property predictions are also emphasized. Finally, future directions for new material exploration, novel processing, fundamental understanding, in-depth characterization, and database assessments are given.

Keywords: high-entropy ceramics (HECs), properties, processing, structure, applications

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Publication history
Copyright
Acknowledgements
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Publication history

Received: 31 January 2021
Revised: 20 March 2021
Accepted: 22 March 2021
Published: 16 April 2021
Issue date: June 2021

Copyright

© The Author(s) 2021

Acknowledgements

The authors would like to thank Dr. Na Ni from Shanghai Jiao Tong University, Dr. Luchao Sun, and Dr. Xiaohui Wang from Institute of Metal Research, Chinese Academy of Sciences, for their helpful discussions. Financial supports from the National Natural Science Foundation of China under Grant Nos. 51972089, 51672064, and U1435206 are also acknowledged.

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