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Metastability in high-entropy alloys: A review

Published online by Cambridge University Press:  10 September 2018

Shaolou Wei ,
Feng He  and
Cemal Cem Tasan Open the ORCID record for Cemal Cem Tasan [Opens in a new window]
Shaolou Wei
Affiliation:
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139,USA
Feng He
Affiliation:
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA; and State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, People’s Republic of China
Cemal Cem Tasan*
Affiliation:
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139,USA
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Classical alloy design strategies often aim to benefit from metastability. Examples are numerous: metastable transformation- and twinning-induced plasticity steels, cobalt or titanium based alloys, age hardenable aluminum alloys, and severe plastic deformed nanostructured copper. In each of these cases, superior engineering property combinations are achieved by exploring limits of stability. For the case of high-entropy alloys (HEAs), on the other hand, majority of present research efforts focus on exploring compositions that would yield stable single-phase structures. HEA metastability and its effects on microstructure and property development constitute only a relatively small fraction of ongoing work. To help motivate and guide a corresponding shift in HEA research efforts, here in this paper, we provide an overview of the research activities on metastability in HEAs. To this end, we categorize the past research on the topic into two groups based on their focus, namely, compositional and structural stability, and discuss the most relevant and exciting findings.

Keywords

high-entropy alloysmetastabilitymicrostructure
Type
Invited Review
Information
Journal of Materials Research , Volume 33 , Issue 19: Focus Issue: Fundamental Understanding and Applications of High-Entropy Alloys , 14 October 2018 , pp. 2924 - 2937
Copyright
Copyright © Materials Research Society 2018 

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Footnotes

b)

These authors contributed equally to this work.

This section of Journal of Materials Research is reserved for papers that are reviews of literature in a given area.

References

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