Electronic and structural properties of low-index L12–Al3Zr surfaces by first-principle calculations. (September 2019)

• Record Type: Journal Article
• Authors: Yang, Tianxing; Han, Xiujun; Ding, Zongye; Wang, Yuanxu; Li, Jianguo
• Is Part Of: Calphad. Volume 66(2019)
• Publication Date: 2019-09
• Subjects: L12 –Al3Zr -- First-principles calculation -- Surface energy -- Atomic relaxation; Phase diagrams -- Data processing -- Periodicals; Thermochemistry -- Data processing -- Periodicals; Diagrammes de phases -- Informatique -- Périodiques; Thermochimie -- Informatique -- Périodiques; Thermodynamica; Electronic journals; 541.363
• DOI: 10.1016/j.calphad.2019.101645
• Languages: English
• ISSNs: 0364-5916

Abstract

Abstract: The atomic relaxations, electronic properties and surface energies of low index L12 -Al3 Zr surfaces were studied by using the first-principles method based on the density functional theory. Five low index surfaces with different terminations are studied systematically. The study shows that atomic relaxations occur mainly within the outermost two layers. The stoichiometric (111), non-stoichiometric (110) and (001) surfaces with different terminations are investigated. The (111) surface which has the lowest surface energy and is independent on the chemical potential of Al atom is found to be the most thermodynamically stable surface. For the non-stoichiometric surfaces, the AlZr terminated (001) surface and Al terminated (110) surface are metastable under an Zr-rich and Al-rich condition respectively. These results are in consistant with the results of density of states. The lattice misfit between α-Al and L12 -Al3 Zr is not more than 1.65% by our calculation, indicating L12 -Al3 Zr is a potent effective heterogeneous nucleating agent for α-Al. Highlights: The surface properties of five low index surfaces of L12 -Al3 Zr are studied by the first principle calculations. The atomic relaxations occur mainly within the outmost and second layers. Five low index surfaces with different terminations are studied, and (111) stoichiometric surface is the most stable one. For the non-stoichiometric surfaces, the stability sequence depends on the chemical potential of Al.