First-Principles Study of AlCrFeMoTi High-Entropy Alloys

The AlCrFeMoTi high-entropy alloy exhibits promising application potential as a corrosion-resistant structural material in advanced nuclear energy systems, particularly in lead–bismuth fast reactors. In this present study, first-principles calculation based on the density functional theory was employed to investigate the phase and electronic structure of AlCrFeMoTi HEA. The Gibbs free energy calculation results and XRD experimental results both indicate that the BCC phase is more stable for AlCrFeMoTi HEA. The atom distribution model was constructed according to the site preference of atoms occupying sublattices. The results indicate that alloying atoms have an obvious site preference. For example, Fe, Mo, and Cr atoms always prefer the 1a sublattice, while Al and Ti atoms tend to favor the 1b sublattice. And the atom site preference is temperature-sensitive. At 973 K, the site occupancy configuration is (Al5Cr16Fe26Mo17Ti0)1a(Al21Cr9Fe0Mo9Ti25)1b. Based on the steady-state phase structure, the band structure, density of states, and charge density were calculated. The electronic structure results show that metal bonds are formed between alloying elements in AlCrFeMoTi HEA, exhibiting strong metallic properties.