The alloy-design strategy of combining multiple elements in near-equimolar ratios has shown great potential for producing exceptional engineering materials, often known as 'high-entropy alloys'. Understanding the elemental distribution, and, thus, the evolution of the configurational entropy during solidification, is undertaken in the present study using the Al₁.₃CoCrCuFeNi model alloy. Here we show that, even when the material undergoes elemental segregation, precipitation, chemical ordering and spinodal decomposition, a significant amount of disorder remains, due to the distributions of multiple elements in the major phases. The results suggest that the high-entropy alloy-design strategy may be applied to a wide range of complex materials, and should not be limited to the goal of creating single-phase solid solutions.

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Deviation from high-entropy configurations in the atomic distributions of a multi-principal-element alloy

The physics of fatigue crack initiation

Structure and stability of Laves phases. Part I. Critical assessment of factors controlling Laves phase stability

https://opus.lib.uts.edu.au/bitstream/10453/41109/3/2-s2.0-84949654966%20am.pdf

Predicting the formation and stability of single phase high-entropy alloys

http://publish.illinois.edu/mechse-html/files/imported/sangid_maier_sehitogliu_ijp.20110408.4d9f59ff0c48a8.29327594.pdf

The role of grain boundaries on fatigue crack initiation - An energy approach

Enthalpies of formation of binary Laves phases

Point defect mechanisms in the binary C15 NbCr{sub 2} and NbCo{sub 2}, and C14 NbFe{sub 2} systems on both sides of stoichiometry was studied and clarified by both bulk density and X-ray lattice parameter measurements. It was found that the vacancy concentrations in these systems after quenching from 1000 C are essentially zero. The constitutional defects on both sides of stoichiometry for these systems were found to be of the anti-site type in comparison with the model predictions. However, thermal vacancies exhibiting a maximum at the stoichiometric composition were obtained in NbCr{sub 2} laves phase alloys after quenching from 1400 C. These could be completely eliminated by annealing at 1000 C. Anti-site hardening was found on both sides of stoichiometry for all three Laves phase systems studied. Furthermore, the thermal vacancies in NbCr{sub 2} alloys after quenching from 1400 C were found to soften the Laves phase. The anti-site hardening of the Laves phases is similar to that of the B2 compounds, while the thermal vacancy softening is unique to the Laves phase. Both the anti-site defects and thermal vacancies do not significantly affect the fracture toughness of the Laves phases.

/pdf/point-defects-in-binary-laves-phase-alloys-2kzod0q1hk.pdf

Lee M. Pike

Papers

Enthalpies of formation of binary Laves phases

Point Defects in Binary Laves-Phase Alloys

Plastic behavior of a nickel-based alloy under monotonic-tension and low-cycle-fatigue loading

Site occupancies, point defect concentrations, and solid solution hardening in B2 (Ni,Fe)Al

Strengthening domains in a Ni-21Cr-17Mo alloy