Atomistic simulation of hardening in bcc iron-based alloys caused by nanoprecipitates

Abstract

The paper presents results of atomistic simulations of hardening in model bcc iron-based alloys due to secondary phase precipitates formation. The simulations are based on shear stress relaxation technique and experimental data on morphology of precipitates. Atomistic methods were developed to reproduce the shear strength of bcc iron-based materials. The large-scale atomistic simulations were carried out for model binary alloys: Fe–Cr imitating low-carbon ferritic and ferritic–martensitic steels and Fe–Cu imitating low-carbon bainitic steel. A representative set of atomic structures is compiled with account for the chemical composition and concentration and size of secondary phase, comparable with those in steels of the considered classes and available experimental data on radiation and thermal induced precipitation. Obtained results on hardening were verified against experimental data and the dispersed barrier hardening model.