First Principles Calculations of Solute Ordering in Mg-Zn-Y Alloys

The formation mechanism of the LPSO structures of Mg-Zn-Y alloys has been investigated by the energetic assessments with the first principles calculations. For the key players of the LPSO structures, the stacking faults and the solute elements of Zn and Y, two scenarios are proposed; one is the stacking fault control and the other is the solute atom pair control. Both of them were declined through the detailed investigations of the energetic assessments. The enrichment of solute atoms induced by the stacking fault is suggested.