First-Principles Study on Preferential Energetics of Mg-based Ternary Alloys Revisited by Short-Range Order in Disordered Phases

Research paper by Ryohei Tanaka, Koretaka Yuge

Indexed on: 03 Oct '16Published on: 03 Oct '16Published in: arXiv - Physics - Materials Science


To investigate the formation process of Mg-based long-period stacking ordered (LPSO) structure, we systematically study the preference of the short-range order (SRO) in disordered phases of Mg- RE-Zn (RE = Y, La, Er, Ho, Dy, Tb) and Mg-Gd-Al ternary alloy systems through first-principles calculation combined with a method based on information of a lattice under spatial constraint. RE-Zn and Gd-Al pair clusters' probability showed the tendency of increasing. In contrast, La-Zn pair clusters' probability is not increasing, whose system dose not form LPSO structure. This preference of SRO in disordered phases of Mg-based ternary alloys indicates that there should be the profound relationship between SRO and forming the characteristic phases in LPSO structures.