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This work presents a study on the surface tension of liquid Aluminum–Nickel (Al–Ni) alloys. Obtaining adequate values of surface tension for this system is not a simple task as these alloys present the formation of atomic clusters with short-range order at certain compositions, which dramatically influences surface tension. The Compound Forming Model predicts the influence of these clusters on surface tension, but experimental limitations have obstructed its validation due to deficient thermodynamic data. This work attempts to overcome some of these limitations by using Molecular Dynamics (MD). By comparing the obtained results from MD simulations with those of an equivalent system without clusters, it was possible to infer the role of the atomic clusters on Al–Ni surface tension. It was found that these clusters increase surface tension by decreasing the Al content at the surface. They achieve this reduction in Al content at the surface by trapping Al atoms and hindering their travel to the surface. [ABSTRACT FROM AUTHOR]

Multi-phase field simulation of Al SB 3 sb Ni SB 2 sb intermetallic growth at liquid Al/solid Ni interface using MD computed interfacial energies. Author Correction: Modeling of surface phenomena of liquid Al-Ni alloys using molecular dynamics Kunwar, A. I et al. i Multi-phase field simulation of Al SB 3 sb Ni SB 2 sb intermetallic growth at liquid Al/solid Ni interface using MD computed interfacial energies. [Extracted from the article]

A quantitative phase-field model has been implemented to study the dissolution behavior of alumina (Al 2 O 3 ) into CaO–Al 2 O 3 –SiO 2 slags. The simulations allowed evaluating the influence of temperature and composition on the diffusion paths and dissolution rates of Al 2 O 3 into CaO–Al 2 O 3 –SiO 2 slags. The results obtained in the simulations are consistent with experimental observations and the predictions from an analytical dissolution model. The phase field simulations show that the dissolution rate of Al 2 O 3 increases with temperature. Increasing CaO at a fixed Al 2 O 3 content or decreasing Al 2 O 3 content at a fixed CaO/SiO 2 ratio also results in a higher dissolution rate of Al 2 O 3 . The results are further interpreted based on thermodynamic and kinetic considerations. [ABSTRACT FROM AUTHOR]

Considering its application in developing Raney-type Ni catalysts and in metal surface coatings, the study on the growth behavior of Al 3 Ni 2 intermetallic compound (IMC) at the Al/Ni material interface is of utmost importance. The present work integrates nanoscale molecular dynamics (MD) calculation with mesoscale phase field model for studying the interfacial phenomena associated with Al 3 Ni 2 growth in Al/Ni interface at 1173.15 K. The interfacial energies computed from MD are in the range 0.9–1.2 J/m 2 with FCC/IMC featuring as the interface with the largest value and IMC/LIQUID as the one with the lowest value. Phase field model parameters characterizing a varying interface energy formulation are established to simulate the 2D growth of interfacial IMC grains. With the help of an atomistically informed phase field model, it has been revealed that the phase areas and morphology are obviously sensitive to the interfacial properties. The methodologies and results of these multiscale simulations for IMC interfaced between Al and Ni microstructures offer the complementary and accelerated design route of in-silico studies for materials systems experimented at high temperature. [Display omitted] • Interfacial energies computed using molecular dynamics. • Atomistically informed phase field simulation of growing IMC grains. • Comparison made between varying interface energy (VIE) and constant interface energy (CIE) models. • IMC area and morphology affected by interfacial properties. [ABSTRACT FROM AUTHOR]

Despite the fact that aluminum is one of the most commonly-used elements, experimental results on the value of its surface tension are largely scattered due to the high sensitivity of aluminum to the atmospheric conditions, leading to huge experimental challenges. In this study, the surface tension of pure Al and Al-O systems was studied thoroughly using Molecular Dynamics (MD) simulations. A force field that includes embedded atoms method and charge transfer ionic potential was applied to account for interatomic interactions. To complement and validate the numerical approach, the surface tension of pure aluminum at two different temperatures was also measured. A good agreement was obtained between the measured and predicted surface tension. Simulations were then performed at different temperatures (1000–2200 K) with different initial oxygen contents to elucidate the effects of well-controlled atmospheric conditions on surface tension. Our results also show that the surface tension of aluminum is sensitive to the amount of oxygen content at the surface, which depends on the total oxygen content and the temperature. At various temperatures, different amounts of oxygen atoms are needed to saturate the aluminum surface (X O Sat.). A relationship between X O Sat. and temperature was derived. We believe that this study can shed light on the underlying mechanisms controlling surface tension of aluminum and could offer routes to better engineer the surface properties of this liquid metal. [Display omitted] [ABSTRACT FROM AUTHOR]