BASAL-PLANE STACKING-FAULT ENERGIES OF Mg: A FIRST-PRINCIPLES STUDY OF Li- AND Al-ALLOYING EFFECTS

摘要

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 (hcp) Mg. The GSFEs were obtained using first-principles technique in combination with climbing-image nudged elastic band methods. Our results show that Li-alloying can facilitate dislocation-mediated process while sequential faulting across basal planes becomes favorable with Al-alloying. Such difference is attributed to that the two alloying elements tend to form different types of bond critical points in Mg.