Multiscale characterization of nanomechanical behavior and dislocation mechanisms in Cantor CrMnFeCoNi HEA using 3D EBSD and atomistic modeling

Abstract

High-entropy alloys (HEAs) are an emerging class of materials renowned for their exceptional mechanical strength, hardness, and resistance to corrosion and irradiation, making them promising candidates for applications in extreme operating conditions. In this study, the nanomechanical response of a single-grain Cantor CrMnFeCoNi HEA, synthesized in-house, is investigated through nanoindentation testing and characterized using three-dimensional Electron Backscatter Diffraction (3D EBSD) reconstruction. This advanced technique enables high-resolution mapping of geometrically necessary dislocation (GND) density and grain reference orientation deviation (GROD) angles, providing critical insights into localized deformation features and strain gradients. To complement the experimental observations, molecular dynamics (MD) simulations were employed to capture atomistic-scale structural responses, achieving qualitative agreement with mesoscale experimental findings. The integration of 3D EBSD and MD simulations underscores the synergy between advanced experimental characterization and computational modeling, revealing complex dislocation nucleation and evolution mechanisms during nanoindentation. This study highlights the potential of combined multiscale approaches to deepen our understanding of deformation phenomena in HEAs.