Doping of Interstitials (H, He, C, N) in CrCoFeNi High Entropy Alloy: A DFT Study

Abstract

The dissolution behavior of H, He, C and N in CrCoFeNi high entropy alloy (HEA) is studied by density functional theory calculation. Results show that the site preference of H, C and N in CrCoFeNi HEA is the octahedral site, while the site preference of He is the tetrahedral site. The dissolution energy of H in CrCoFeNi HEA is the lowest and that of He is the highest. The high dissolution energy of He is considered to be due to its closed-shell electronic structure. Moreover, results suggest that the H, He and N are more stable at the site with more Cr atoms, and C is more stable at the site with less Ni atoms. Furthermore, It is found that H, He, C and N have the effect in decreasing the magnetic moments of solutes in CrCoFeNi HEA. Electronic structure analysis shows that, for C and N, there is strong hybridization between them and solutes. It implies the chemical bonding between C, N and solutes is strong.

The doping of H, He, C and N in CrCoFeNi High entropy alloy.