Manufacturing Methods, Microstructural and Mechanical Properties Evolutions of High-Entropy Alloys: A Review

Abstract

High entropy alloys (HEAs) are being attracted recently by several researchers, scientists, and academicians to achieve extraordinary and outstanding properties that cannot be obtained from conventional alloys. HEAs are multicomponent alloys in which a minimum of five metallic elements are mixed in an equal molar or non-equal molar ratio. The rapid growth of this field produces a huge amount of scientific papers over the last decade. However, still, there is a need to review various manufacturing methods and their results. Also, the outcome of the scientific articles related to HEAs has ignored the various methods of synthesizing and manufacturing. In this review article, an attempt was made and largely concentrated on the methods and techniques that can be used in the manufacturing and synthesizing of the HEAs. Recently, the properties of HEAs become much better when compared to conventional alloys. Some techniques have succeeded in producing ultrafine microstructure grains which become a leap in industrial fields. Now, the manufacturing methods of conventional alloys are almost familiar and implemented according to the suggestions given by the researchers and academicians based on their work. Therefore, the present review article has demonstrated various methods of manufacturing of HEAs with novel schematics with a preview description for more understanding of the basic work criteria. Besides, this article has reviewed the outcomes of several research articles related to several methods, then compared the outcome of each method with the corresponding mechanical properties, and major challenges of HEAs are discussed and reported.

Powder metallurgy of Al0.1CoCrFeNi high-entropy alloy

“…For engineering alloys, the yield strength can be dictated by the strengthening factors like intrinsic lattice friction (σ LF ), solid solution strengthening (σ SSS ), grain boundary strengthening/Hall-Petch strengthening (σ HP ), dislocation strengthening (σ dislo ), and particle dispersion strengthening (σ disp ). The yield strength of the alloy can be predicted by using the formula given in the following equation [75,76,77,78,79]:…”

Microstructure Evolution in a Fast and Ultrafast Sintered Non-Equiatomic Al/Cu HEA

“…The formal use of HEA families is still on hold for industrial applications due to the lacking research into the properties these alloys [30]. Nonetheless, it is also necessary to evaluate viable processing routes.…”

“…These disadvantages with such fast techniques are being overcome as new technology advances and industrial patents emerges [31], though slowly. Regarding the P&S sintering route, this process is simple and economical as it is still being used in the mass production industries at a cost of performance [30].…”

Rapid Consolidation of WC-ZrSiO4 Hard Materials by Spark Plasma Sintering: Microstructure, Densification, and Mechanical Properties

“…When maching conductive materials (workpiece) that heat up rapidly due to the discharge of electrictiy, the Co phase on the surface of the cemented carbide dissolves. This leads to the formation of a molten layer, which in turn causes the softening of the cutting tool [6,7]. Furthermore, surface corrosion may occur owing to the ionization of Co caused by the cutting oil or grinding fluid used during wet working.…”