An Atomistic Modeling Study of the Relationship between Critical Resolved Shear Stress and Atomic Structure Distortion in FCC High Entropy Alloys — Relationship in Random Solid Solution and Chemical-Short-Range-Order Alloys —

Abstract

The relationship between the critical resolved shear stress (CRSS) at T = 0 K and the atomic structure distortion was studied using molecular dynamics (MD) simulation with atomic distortion (root-mean-square-atomic-displacement (RMSAD)) controlled Lennard-Jones (LJ) interatomic potentials for different face-centered-cubic (FCC) high entropy alloy (HEA) systems, such as ternary, quaternary, and quinary alloy systems. We demonstrated that an almost universal linear relationship exists between CRSS and RMSAD for the random solid solution (RSS) of these alloy systems. The universality was also confirmed by a more realistic embedded atom method (EAM) potential. However, alloy systems that have a chemical-short-range-order (CSRO) do not follow this universal linear relationship.