Basal-plane stacking-fault energies of Mg: A first-principles study of Li- and Al-alloying effects

Alloying effects due to Li and Al were examined in terms of generalized stacking-fault energies (GSFEs) associated with basal planes of hexagonal close-packed Mg. The GSFE profiles were obtained using a first-principles technique in combination with climbing-image nudged elastic band methods. Our results show that Li alloying can facilitate dislocation-mediated processes while sequential faulting across basal planes becomes favorable with Al alloying. Such a difference is attributed to the fact that the two alloying elements tend to form different types of bond critical points in Mg. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.