First principles investigation of β′-short and β′-long in Mg-Gd alloy

We use density functional theory calculations to explain why β′-long instead of β′-short forms during age-hardening process in Mg-Gd alloys. We calculate strain energies and interfacial energies of β″, β′-short and β′-long in Mg-Gd alloys and find that (1) results of strain energies and interfacial energies of β″ agree well with other theoretical works (2) habit plane of β′-long predicted by density functional theory calculations is consistent with experimental observation (3) strain energy is mainly responsible for the formation of β′-long instead of β′-short in the age-hardening process.