Brief Evolution Story and some Basic Limitations of High Entropy Alloys (HEAs) – A Review. (2019)

• Record Type: Journal Article
• Authors: Kishore Reddy, Ch.; Gopi Krishna, M.; Srikant, P.
• Is Part Of: Materials today. Volume 18:Part 1(2019)
• Page Start: 436
• Page End: 439
• Publication Date: 2019
• Subjects: High entropy alloy(HEA) -- High Strength alloy(HSA) -- Multi component alloys(MCAs) -- Compositionally Complex Alloys (CCAs); Materials science -- Congresses -- Periodicals; 620.1
• DOI: 10.1016/j.matpr.2019.07.256
• Languages: English
• ISSNs: 2214-7853

Abstract

Abstract: High entropy alloys (HEAs) are the area of youngest in regard materials and manufacturing focus as if we consider a century of development of alloys in the chronological order of age span of steels to super alloys. Some authors called them as Multi-component alloys (MCAs) while some as High strength alloys (HSAs). Of course, many investigators called them as Compositionally Complex Alloys (CCAs) as the name indicates the complexity in understanding the behavior of them. Hardly 12 to 15 years ago has the research in this area initiated. The HEAs area opens a wide spectrum of research space for work on newer materials. Due to over whelmed exhibition in mechanical, structural, electrical and chemical properties of the HEAs, the researchers deliberately adopt and exploring newer ideas and combinations of techniques for further findings in depth of emerging development in this novel area. Not readily the HEAs can comprise through conventional or stir casting, powder metallurgy, and surface-coating like conventional methods, nevertheless eventually covers many modern technical methods like stir-friction welding, rapid solidifying methods, extrusion reciprocation, spray-forming methods, spark plasma sintering technique, nano-material forming, thermo-mechanical and chemical treatments etc., in a wider range of applications. For a special intended application of a rare area with stringent need, with no doubt a specific proper alloying of elemental composition under suitable processing method, a HEA can meet the need of properties of that particular stringent case. Ultimate aim of development of HEAs may not only meet the specific need of application in sever conditions, also provide longer life with enhanced service which in turn may reduce the cost of production, production time and even afford energy saving. In this paper, some of the cases of HEAs which suits specific applications as well as some production techniques which reveals whether there is the near or mere toil or fearful toil involved for their effective preparatione.