The orientation dependence of liquid ordering at α-Al2O3/Al solid–liquid interfaces: A molecular dynamics study

• Published in: Computational materials science Vol. 174; p. 109489
• Main Authors: Yan, R., Sun, W.Z., Ma, S.D., Jing, T., Dong, H.B.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2020
• Subjects: Liquid ordering; Molecular dynamics simulation; ReaxFF; Solid–liquid interface; Temperature effect; ReaxFF; Temperature effect; Solid–liquid interface; Molecular dynamics simulation; Liquid ordering
• ISSN: 0927-0256; 1879-0801
• DOI: 10.1016/j.commatsci.2019.109489

[Display omitted] •Atoms from the liquid would first form a layer to fulfill the crystal periodicity.•Layers at (0 0 0 1) interface exhibit a structure similar to the (1 1 1) plane in FCC Al.•Layers at (112-0) interface show a hexagonal structure.•Distances between neighboring liquid layers do not show a dependence on temperature.•Correlation lengths were extracted and compared with experimental ones. In this study, the evolution of ordering in liquid Al adjacent to α-Al2O3 substrates with (0 0 0 1) and (112-0) surface orientations was examined using a reactive force field (ReaxFF) and molecular dynamics (MD) simulation. It is found that atoms from the liquid would first form a layer at the (0001) or (112-0) interfaces to fulfill the crystal periodicity. Atoms in this layer adopt the in-plane structure of the substrate and lack mobility. Once the crystal periodicity is fulfilled, liquid layers near the (0 0 0 1) interface exhibit an in-plane structure similar to the (1 1 1) plane in face-centered cubic (FCC) Al, while liquid layers near the (112-0) interface show a hexagonal structure. Distances between neighboring liquid layers do not show a dependence on temperature, but the extent of ordering in liquid Al increases with decreasing temperature.