Periodic Maximum Entropy Random Structure Models for High-Entropy Alloys

Abstract

Periodic chemically homogenized high-entropy alloy structures are constructed according to maximum entropy principle. The method can efficiently generate equimolar and non-equimolar high-entropy alloy atomic structures. Nine high-entropy alloys are simulated based on the constructed models using density functional theory techniques. The calculated lattice parameters are consistent with the available experimental data. The calculated enthalpies of mixing are more negative than the values estimated by using Miedema model, due to severe lattice distortion. The lattice distortion parameters were calculated. The results showed that fcc structure tend to stable with smaller and bcc structure with larger. The bulk modulus of Al1.5CoCrNiFe high-entropy alloys was fitted and the value is consistent with the available experimental data.

High-entropy alloy screening for halide perovskites

“…The equimolar unit cell volume's mean, standard deviation, and coefficient of variation are:Here V̄ is equimolar unit cell volume, σ is equimolar alloy unit cell volume standard deviation, UCV is equimolar alloy unit cell volume coefficient of variation, and N is the number of end-members. Atomic radius differences, 62–64 lattice parameter differences, 65,66 and atomic position differences 67 have been previously parameterized to screen metal HEA. We instead parameterize unit cell volume to extend the approach to non-cubic crystals.…”

A Review of Multi-Scale Computational Modeling Tools for Predicting Structures and Properties of Multi-Principal Element Alloys

“…Some researchers have utilized Monte Carlo simulations which are a broad range of computerized mathematical algorithms to study the probability of different objectives [76]. For example, Anzorena et al [77] investigated the evolution probabilities with temperature for different coordination matrices in MoTaVWZr, and Feng et al [78] calculated the pair correlation functions in AlCoCrFeNi; both work employed Monte Carlo simulations. In another work, hybrid Monte Carlo and MD (hybrid MC/MD) approach was used to simulate the structure and calculate the partial radial distribution functions in Al 1.33 CoCrFeNi MPE alloy ( Figure 6) [79].…”