Hardening in thermally-aged Fe-Cr binary alloys: Statistical parameters of atomistic configuration

By exploiting Monte Carlo methodology and molecular dynamics, we computationally simulate the spinodal decomposition of iron-chromium binary alloys and analyze the relationship between the increase of yield strength induced by the phase separation phenomenon, and statistical parameters of the atomistic configuration. We successfully model the experimentally-discovered proportional relationship between the hardness and the variation parameter (or V), and also found that the adequacy of the parameter V as an empirical indicator of hardening is limited, because it does not properly capture short-range atomistic configurations that influence the hardening. We suggest that the short-range-order parameter has more potential to become universal descriptor of the phenomenon.