Chemical short-range order in body-centered-cubic TiZrHfNb high-entropy alloys

We have carried out detailed density functional theory-based Monte Carlo simulations to explore the characteristic chemical short-range order (CSRO) in TiZrHfNb, which is a representative body-centered-cubic refractory high-entropy alloy (HEA). The salient feature observed is the preference for Ti-Zr and Nb-Hf nearest-neighbor environments, which also explains the distribution pattern of O interstitials toward the formation of (Ti,Zr,O)-enriched ordered complexes. We also report certain small but noticeable changes in key material parameters due to the presence of CSROs, including elastic moduli, misfit volume, and predicted yield strength, which offer useful structure–property information for improving the design of highly concentrated HEA solid solutions.