Atomistic Insights into the Irradiation Resistance of Co-Free High Entropy Alloy FeMnNiCr

Abstract

We have investigated the displacement cascade irradiation resistance behavior of a cobalt-free high entropy alloy FeMnNiCr using molecular dynamics simulations. The results show that defects in FeMnNiCr form in small clusters, and their migration is significantly inhibited, leading to a higher defect recombination rate and a lower number of residual defects compared to Ni. Additionally, FeMnNiCr exhibits a longer thermal peak life and lower thermal conductivity compared to Ni, providing a longer time for defect migration and combining. The migration of defect clusters in FeMnNiCr displays three-dimensional properties, attributed to its high chemical disorder. After prolonged irradiation, defects in FeMnNiCr stabilize as small clusters, whereas point defects in Ni tend to form large defect clusters and evolve into dislocations. Considering the feature of absence of the element cobalt, our results imply that FeMnNiCr has great potential in application in nuclear energies.