Twenty years of the CoCrFeNiMn high-entropy alloy: achieving exceptional mechanical properties through microstructure engineering

The CoCrFeNiMn multicomponent is one of the most widely and best studied of all high -entropy alloys (HEAs) since its exceptional properties suggest potential uses as a struc-tural material in many industrial applications. In practice, a good balance between strength and ductility is one of the most important challenges in developing alloys in modern materials science and engineering. There have been many attempts to overcome the strength-ductility trade-off in the CoCrFeNiMn alloy due to its relatively low strength. These attempts include adding a minor sixth element, such as oxide or carbide particles, and also developing thermomechanical processing for grain refinement or precipitation to produce a tailored microstructure with optimum mechanical properties. This review de-scribes the deformation mechanisms and the microstructural evolutions in this alloy during plastic deformation under different conditions of temperature, strain and strain rate where these are important for the processing and manufacturing of the alloy. In addition, this study provides a perspective on the behavior of the alloy under high tem-perature exposure and also under cyclic loading which is generally the most important factor in industrial applications. This understanding demonstrates that there is a very large potential for the future enhancement and optimization of this and other comparable HEAs. ?? 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Automated summary

The CoCrFeNiMn alloy, a multicomponent high-entropy alloy (HEA), has been extensively studied due to its exceptional properties and potential industrial applications. However, there is a challenge of achieving a balance between strength and ductility, which can be addressed by adding a sixth element or applying thermomechanical processing. This review focuses on the deformation mechanisms and microstructural evolutions of the alloy under different conditions, providing insights for its processing and manufacturing. Additionally, the behavior of the alloy under high temperature exposure and cyclic loading is discussed, highlighting the potential for future enhancement and optimization of this and other comparable HEAs.