Atomic-scale models for hardening in fcc solid solutions

Abstract

Atomic-scale simulations are associated with an elastic line model to analyze thoroughly the pinning strength experienced by an edge dislocation in some face-centered-cubic solid solutions, Al(Mg) and Ni(Al) with solute concentration comprise between 1 and $10\text{ }\text{at}\text{.}\text{ }\mathrm{%}$. The one-dimensional elastic line model is developed to sketch out the details of the atomic scale. The account of such details is shown to yield a proper description of the dislocation statistics for the different systems. The quantitative departure between hardening in Al(Mg) and Ni(Al) is then demonstrated to hinge on the difference in the short-range interaction between the partial dislocations and the isolated impurities. It is also shown that an accurate description of the solid-solution hardening requires the account for the dislocation geometry and the dislocation interaction with clusters of solute atoms. The elastic line model allows us to perform some computations at the microscopic scales meanwhile accounting for the most important atomic details. A comparison with experimental data is attempted.