Structure and dynamics of liquid Al1-xSix alloys by ab initio molecular dynamics simulations

TitleStructure and dynamics of liquid Al1-xSix alloys by ab initio molecular dynamics simulations
Publication TypeJournal Article
Year of Publication2009
AuthorsWang SY, Wang CZ, Zheng CX, Ho KM
Journal TitleJournal of Non-Crystalline Solids
Volume355
Pages340-347
Date Published03/01
ISBN Number0022-3093
Accession NumberISI:000264595400002
Keywordsab initio, aluminum, cooling rate dependence, glass, liquid alloys and liquid metals, melt, metals, molecular dynamics, short-range order, solidification, total-energy calculations, wave basis-set
Abstract

First-principles molecular dynamics (MD) simulations are performed to study the structure and dynamics of liquid Al1-xSix (x = 0.0, 0,12, 0.2, 0.4, 0.6. 0.8) at the temperature of 1573 K. The composition dependence of static structure factors, pair correlation functions, and diffusion constants are investigated. We found that the structure of the liquid Al1-xSix alloys is strongly dependent on the composition. From our simulation and analysis, we can see that although liquid Al1-xSix is metallic, there are some degrees of covalent tetrahedral short-range order in the liquid. The degree of tetrahedral short-range order increases linearly as the Si concentration in the liquid increased. The diffusion coefficients of both Al and Si atoms in liquid Al1-xSix alloys at 1573 K are not very sensitive to the composition. (C) 2009 Elsevier B.V. All rights reserved.

URL<Go to ISI>://000264595400002
DOI10.1016/J.Jnoncrysol.2009.01.007