High-Temperature Oxidation of High-Entropic Alloys: A Review

Abstract

Over the past few years, interest in high-entropic alloys (HEAs) has been growing. A large body of research has been undertaken to study aspects such as the microstructure features of HEAs of various compositions, the effect of the content of certain elements on the mechanical properties of HEAs, and, of course, special properties such as heat resistance, corrosion resistance, resistance to irradiation with high-energy particles, magnetic properties, etc. However, few works have presented results accumulated over several years, which can complicate the choice of directions for further research. This review article presents the results of studies of the mechanisms of high-temperature oxidation of HEAs of systems: Al-Co-Cr-Fe-Ni, Mn-Co-Cr-Fe-Ni, refractory HEAs. An analysis made it possible to systematize the features of high-temperature oxidation of HEAs and propose new directions for the development of heat-resistant HEAs. The presented information may be useful for assessing the possibility of the practical application of HEAs in the aerospace industry, in nuclear and chemical engineering, and in new areas of energy.

Aspects of Applied Chemistry Related to Future Goals of Safety and Efficiency in Materials Development for Nuclear Energy

“…These alloys may replace the conventional ones, such as Ni-based superalloys or SiC, being well suited for use in extreme environments such as nuclear and aerospace applications [ 197 , 198 , 199 ]. The mechanisms of high-temperature oxidation of HEAs are presented in a recent review by Veselkov et al [ 200 ].…”

Mechanistic Understanding of Speciated Oxide Growth in High Entropy Alloys

“…Since HEAs have been often designed keeping mechanical properties as the central modality, signi cant challenges in the corrosion and oxidation-resistant of these alloys exist due to the consequences of creating highly entropic surfaces with an excess of asymmetrically interacting elements. At temperatures exceeding 500°C, the oxidation behavior of traditional and advanced alloys (e.g., Ni-Cr, Ni-based superalloys, Fe-Cr, CoCrFeNiMn 'Cantor' alloy) has been extensively studied in oxygen-rich environments and over extended periods (from days to hundreds of days 5,[10][11][12][13][14][15][16][17][18][19][20] ). The oxidation process is in uenced by variables such as temperature, external oxygen pressure, and alloy composition.…”

Al0.25CoCrFeNiV High Entropy Alloy Coating Deposited by Laser Cladding on Stainless Steel

“…Alloys consisting of five or more components in an equimolar ratio to achieve maximum mixing entropy were first studied by Cantor and Yeh in 2004 [ 1 , 2 ] and were called “high entropy alloys” (HEAs). Such alloys based on transition metals of the Fe subgroup (in particular, of the Al x CoCrFeNi type) demonstrate a unique combination of mechanical characteristics [ 3 , 4 ]; further studies showed their excellent tribological properties [ 5 , 6 ] and high corrosion resistance [ 7 , 8 ].…”