Mechanically alloyed high entropy alloys: existing challenges and opportunities

High entropy alloys (HEAs) for the first time were reported in 2004, however, the progress in this field was markedly realized since 2010 when a drastic upsurging demand of HEAs was observed owing to their unique properties and possibilities to form various compositions significantly grabbing the attention of academia and researchers. Initially, the main focus of researchers was on equiatomic HEAs which later paradigm shifted to non-equiatomic alloys. With progress in the research, four core effects were examined as the predomi-nant factors enabling the distinguished properties. Amongst, mechanical alloying (MA) followed by the sintering route grabbed the attention of all the researchers dealing with the processing of HEAs. Therefore, the basic objective of this review is to critically discuss the mechanically alloyed HEAs, functional properties, and their applications. Subsequently, the existing challenges and their opportunities are also discussed which leads this review article towards uniqueness and novelty.(c) 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

High entropy alloys (HEAs) were first reported in 2004, but significant progress in this field has been made since 2010 due to their unique properties and the ability to form various compositions. Researchers initially focused on equiatomic HEAs and later shifted to non-equiatomic alloys. Mechanical alloying and sintering were identified as effective methods for processing HEAs. This review discusses the properties, functional properties, and applications of mechanically alloyed HEAs, as well as the existing challenges and opportunities.