LAUSR

Abstract For dislocations in non-basal planes in hexagonal close-packed crystalline solids, the corresponding generalized stacking faults (GSFs) are not unique, and the resultant changes of generalized stacking fault energies (GSFEs) by solutes have different trends. We calculate all possible different changes with regards to different solute sites and solute concentrations in an example of { 1 0 1 ¯ 1 } 〈 1 1 2 ¯ 0 〉 slip system in Mg-Y alloy. These results are employed to evaluate the comprehensive effect of yttrium, which shows yttrium enables dislocations of this type to be more mobile in Mg. Our study also demonstrates that the ultimate effect of yttrium is dominated by the decreased GSFEs. In order to understand the origin of the GSFE changes, the mechanical contributions to the GSFEs are discussed.