Atomic-scale mechanisms of annealing induced strengthening in FeNiCrCuAl high entropy alloy: a molecular dynamics study

The deformation behavior and structural evolution of FeNiCrCuAl high entropy alloy (HEA) under different annealing temperatures were systematically studied using molecular dynamics simulations. Pair distribution function analysis confirmed that the short- and medium-range atomic structures remain stable up to 1023 K, indicating excellent thermal stability. Simulated mechanical results revealed that annealing enhances the ultimate tensile strength without significantly affecting the elastic properties. This strengthening is primarily attributed to annealing-induced structural relaxation, which delays the nucleation and propagation of shear transformation zones. Dislocation analysis showed an increased dislocation density in annealed models, leading to stronger dislocation interactions and enhanced work-hardening. Simultaneously, the average atomic potential energy decreases after annealing, reducing atomic mobility and increasing the energy barrier for plastic deformation. The evolution of atomic shear strain correlates with dislocation activity and local structural transformations. Together, these microstructural indicators, dislocation density, atomic potential energy, and shear strain, serve as effective descriptors of the alloy’s deformation mechanisms. This study provides atomic-scale insights into the thermally induced modulation of HEA plasticity and offers a theoretical basis for optimizing HEA performance through thermal treatment.

Text 124094.pdf - Published Version Restricted to Repository staff only Download (3MB) Official URL or Download Paper: https://link.springer.com/article/10.1007/s11661-0...

Actions (login required)

View Item