Microstructure stability and oxidation behaviour of (FeCoNiMo)₉₀(Al/Cr)₁₀ high-entropy alloys

Abstract

Simple ordered L12 phase and complex ordered µ phase were found in the (FeCoNiMo)90Al10 alloy, while disordered FCC and µ phases were detected in the (FeCoNiMo)90Cr10 alloy. After annealing at 900°C, nano-size precipitates were observed in the L12 phase, and splitting and spheroidisation were occurred in some regions of the eutectic structures in the (FeCoNiMo)90Cr10 alloy. After holding for 100 h at 900°C, (FeCoNiMo)90Al10 alloy showed an excellent hardness resistance. The oxidation kinetics of both (FeCoNiMo)90Al10 and (FeCoNiMo)90Cr10 alloys followed a parabolic rate law at 900°C. An external layer of Al2O3 and an underlying MoO2 subscale were found in the (FeCoNiMo)90Al10 alloy. A semi-continuous oxide layer of MoO2 and Cr2O3 was observed in the (FeCoNiMo)90Cr10 alloy.

Microstructure, high-temperature oxidation and molten salt corrosion behaviour of CoCrFeNiAl0.1-RE HEA

“…High-entropy alloys (HEAs) were first proposed as a new multicomponent alloy by Junwei Ye [1] and Cantor [2] and others successively. Unlike the design concept of conventional alloys, HEAs contain five or more major elements and the atomic fraction of each major element ranges from 5 to 35% [3][4][5]. Since HEAs have high mixing entropy, low mixing enthalpy and small atomic size differences; which can cause lattice distortion and slow synergistic diffusion effects, HEAs tend to have a simple solid solution structure and are less prone to complex phases or hard and brittle intermetallic compounds [6,7].…”

Electrical resistivity and oxidation behavior of Cu and Ti doped laser deposited high entropy alloys

“…HEAs can be made from minor elements with <5 at.% attributed to their solid solution phases and their higher mixing entropies (Tsai and Yeh, 2014). These characteristic solid solution phases give HEAs attractive properties such as excellent elevated temperature strength (Hsu et al , 2011), hardness (Zhou et al , 2007; Xin et al , 2021), wear resistance (Chuang et al , 2011; Jin et al , 2018), corrosion resistance (Kao et al , 2010), thermal stability (Tsai et al , 2011; Chen et al , 2019) and electrical and magnetic properties (Kao et al , 2011). According to Arif et al (2021), HEAs are potential materials for several applications and industries such as petrochemical, canning and bottling industries, nuclear fusion and fission reactors, energy storage, automobile, biomedical, marine equipment and aerospace turbine blades application (Arif et al , 2022; Maulik et al , 2018).…”

Characterisation of AlCrCuFeMox high entropy alloys for nuclear fuel cladding

“…The high mixing entropy effect allows the HEAs to easily form singlephase solid solutions, which can reduce the effect of galvanic corrosion and the number of micro batteries, and thereby improving the corrosion resistance. Due to the cocktail effect, HEA will have properties unmatched by traditional alloys, including high hardness, wear resistance, corrosion resistance, and thermal stability [14][15][16][17][18][19][20][21]. Gwalani et al [22] studied the stability of ordered precipitates in face centred cubicbased (FCC) HEAs Al 0.3 CuFeCrNi 2 and found that precipitates are stable at both 500°C and 700°C, which indicates that some HEAs have high microstructural stability.…”