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Title: High-entropy alloys

Abstract

We present that alloying has long been used to confer desirable properties to materials. Typically, it involves the addition of relatively small amounts of secondary elements to a primary element. For the past decade and a half, however, a new alloying strategy that involves the combination of multiple principal elements in high concentrations to create new materials called high-entropy alloys has been in vogue. The multi-dimensional compositional space that can be tackled with this approach is practically limitless, and only tiny regions have been investigated so far. Nevertheless, a few high-entropy alloys have already been shown to possess exceptional properties, exceeding those of conventional alloys, and other outstanding high-entropy alloys are likely to be discovered in the future. In this paper, we review recent progress in understanding the salient features of high-entropy alloys. Model alloys whose behaviour has been carefully investigated are highlighted and their fundamental properties and underlying elementary mechanisms discussed. Finally, we also address the vast compositional space that remains to be explored and outline fruitful ways to identify regions within this space where high-entropy alloys with potentially interesting properties may be lurking.

Authors:
ORCiD logo [1];  [2]; ORCiD logo [3]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)
  2. Max-Planck-Institut für Eisenforschung, Düsseldorf (Germany)
  3. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division
OSTI Identifier:
1550755
Grant/Contract Number:  
AC05-00OR22725
Resource Type:
Accepted Manuscript
Journal Name:
Nature Reviews. Materials
Additional Journal Information:
Journal Volume: 4; Journal Issue: 8; Journal ID: ISSN 2058-8437
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

George, Easo P., Raabe, Dierk, and Ritchie, Robert O. High-entropy alloys. United States: N. p., 2019. Web. doi:10.1038/s41578-019-0121-4.
George, Easo P., Raabe, Dierk, & Ritchie, Robert O. High-entropy alloys. United States. doi:10.1038/s41578-019-0121-4.
George, Easo P., Raabe, Dierk, and Ritchie, Robert O. Tue . "High-entropy alloys". United States. doi:10.1038/s41578-019-0121-4.
@article{osti_1550755,
title = {High-entropy alloys},
author = {George, Easo P. and Raabe, Dierk and Ritchie, Robert O.},
abstractNote = {We present that alloying has long been used to confer desirable properties to materials. Typically, it involves the addition of relatively small amounts of secondary elements to a primary element. For the past decade and a half, however, a new alloying strategy that involves the combination of multiple principal elements in high concentrations to create new materials called high-entropy alloys has been in vogue. The multi-dimensional compositional space that can be tackled with this approach is practically limitless, and only tiny regions have been investigated so far. Nevertheless, a few high-entropy alloys have already been shown to possess exceptional properties, exceeding those of conventional alloys, and other outstanding high-entropy alloys are likely to be discovered in the future. In this paper, we review recent progress in understanding the salient features of high-entropy alloys. Model alloys whose behaviour has been carefully investigated are highlighted and their fundamental properties and underlying elementary mechanisms discussed. Finally, we also address the vast compositional space that remains to be explored and outline fruitful ways to identify regions within this space where high-entropy alloys with potentially interesting properties may be lurking.},
doi = {10.1038/s41578-019-0121-4},
journal = {Nature Reviews. Materials},
number = 8,
volume = 4,
place = {United States},
year = {2019},
month = {6}
}

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