Fluctuations in local shear-fault energy produce unique and dominating strengthening in metastable complex concentrated alloys.

ABSTRACT: Local chemical short-range ordering (SRO) and spatial fluctuations of planar fault energy are important features of multi-element and metastable complex concentrated alloys (CCAs). Arising from them, dislocations in such alloys are distinctively wavy in both static and migrating conditions; yet, such effects on strength have remained unknown. In this work, molecular dynamics simulations are used to show that the wavy configurations of dislocations and their jumpy motion in a prototypic CCA of NiCoCr are due to the local fluctuations of the energy of SRO shear-faulting that accompanies dislocation motion, with the dislocation getting pinned at sites of hard atomic motifs (HAMs) associated with high local shear-fault energies. Unlike the global averaged shear-fault energy which in general wi

SUBMITTER: Li W 

PROVIDER: S-EPMC10041143 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature