hide
Free keywords:
Ab initio; Al alloys; DFT; Peierls-Nabarro model; Solid-solution strengthening
Abstract:
We propose an approach for the computationally efficient and
quantitatively accurate prediction of solid-solution strengthening. It
combines the 2-D Peierls-Nabarro model and a recently developed
solid-solution strengthening model. Solid-solution strengthening is
examined with Al-Mg and Al-Li as representative alloy systems,
demonstrating a good agreement between theory and experiments within the
temperature range in which the dislocation motion is overdamped. Through
a parametric study, two guideline maps of the misfit parameters against
(i) the critical resolved shear stress, tau(0), at 0 K and (ii) the
energy barrier, Delta E-b, against dislocation motion in a solid
solution with randomly distributed solute atoms are created. With these
two guideline maps, tau(0) at finite temperatures is predicted for other
Al binary systems, and compared with available experiments, achieving
good agreement. (C) 2014 Acta Materialia Inc. Published by Elsevier Ltd.
All rights reserved.