Interfacial free energies, nucleation, and precipitate morphologies in Ni-Al-Cr alloys: Calculations and atom-probe tomographic experiments

Biaxial zero creep experiments based on the Josell model were performed on Ag/Fe multilayer thin films to determine their interfacial free energies. Various multilayer samples on stiff wafers prepared by RF magnetron sputtering were subjected to annealing of long duration at 550°C, while a substrate curvature technique was employed for real-time film stress monitoring. Sufficient plastic flow in films makes possible a zero creep equilibrium state to present during this isothermal process, and as a result the interfacial free energies in multilayer interfaces are equilibrated with the elastic strain energies arising from the substrate bending. There is no collapse in the annealed multilayer structures. They are still stably layer-built and exhibit a column grain distribution. XRD results show that Ag and Fe layers have (111) and (110) preferred orientations, respectively. In accordance with a revised Josell model, the equilibrium stresses were measured and the Ag (111)/ Fe (110) interface free energy at 550°C was found to be 0.97 ± 0.13 J/m 2.

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Methods to extract interfacial free energies of flat and curved interfaces from computer simulations

The European Physical Journal Special Topics ◽

10.1140/epjst/e2009-01170-y ◽

2009 ◽

Vol 177 (1) ◽

pp. 103-127 ◽

Cited By ~ 19

Author(s):

M. Schrader ◽

P. Virnau ◽

D. Winter ◽

T. Zykova-Timan ◽

K. Binder

Keyword(s):

Computer Simulations ◽

Free Energies ◽

Interfacial Free Energies

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The Effect of Interfacial Free Energies on the Stability of Microlaminates

MRS Proceedings ◽

10.1557/proc-652-y1.3 ◽

2000 ◽

Vol 652 ◽

Author(s):

A. C. Lewis ◽

A. B. Mann ◽

D. van Heerden ◽

D. Josell ◽

T. P. Weihs

Keyword(s):

Electron Microscopy ◽

Grain Boundary ◽

High Temperatures ◽

Free Energies ◽

Microstructural Stability ◽

Creep Tests ◽

Interfacial Energies ◽

Transmission Electron ◽

The Stability ◽

Interfacial Free Energies

ABSTRACTLaminated composites with polycrystalline layers typically break down at high temperatures through grain boundary grooving and the pinch-off of individual layers. Such materials, when exposed to high temperatures, develop grooves where grain boundaries meet the interfaces between layers. The depths of the grooves are controlled by the ratios of grain boundary and interfacial free energies, γgb/γint. Depending on the dimensions of the grains, these grooves can extend through the entire layer, causing pinch-off at the grain boundary. This pinch-off destroys the layering and eventually leads to a gross coarsening of the microstructure. Because microstructural stability is critical to performance for most applications, the ability to understand and predict the stability of microlaminates is a necessary tool. An existing model of this capillarity-driven breakdown requires the interfacial free energies, γgb and γint, as input parameters. Both biaxial and uniaxial zero creep tests have been used in conjunction with transmission electron microscopy to measure these interfacial energies in Ag/Ni and Nb/Nb5Si3 microlaminates.

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Temperature-Dependent Wettability of Water on a Nickel Surface at Pressurized Condition: A Molecular Dynamics Study

ASME 2019 Heat Transfer Summer Conference ◽

10.1115/ht2019-3521 ◽

2019 ◽

Cited By ~ 1

Author(s):

Dong-Lei Zeng ◽

Biao Feng ◽

Jia-Wen Song ◽

Li-Wu Fan

Keyword(s):

Contact Angle ◽

Hydrogen Bonds ◽

Average Energy ◽

Contact Angles ◽

Nickel Surface ◽

Free Energies ◽

Water Droplets ◽

Temperature Dependent ◽

Interfacial Free Energies ◽

Solid Liquid

Abstract Temperature-dependent wettability of water droplets on a metal surface in a pressurized environment is of great theoretical and practical significance. In this paper, molecular dynamic simulation is used to study this problem by relating the temperature-dependent apparent contact angles to the changes in solid-liquid and solid-vapor interfacial free energies and hydrogen bonds in the nano-sized water droplets with increasing the temperature. The temperature range of interest is set from 298 K to 538 K in a 20 K interval under a constant pressure of 7 MPa. The results show that the contact angle in general decreases with raising the temperature and decreasing trend can be divided into two sections with different slopes. The contact angle drops slowly when the temperature is below 458 K as a critical point. Beyond this point, the contact angle shows a much steeper decrease. The difference between solid-vapor and solid-liquid interfacial free energies is found to decrease slightly with temperature. Combining with that the surface tension drops with increasing the temperature, a decreasing trend of the contact angle is expected according to the Young’s equation. As the temperature increases, the number and average energy of the hydrogen bonds both decrease, and the hydrogen bonds tend to aggregate at the bottom of the nano-droplets.

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On simulation methods to compute surface and interfacial free energies of disordered solids

The Journal of Chemical Physics ◽

10.1063/1.1470199 ◽

2002 ◽

Vol 116 (19) ◽

pp. 8547 ◽

Cited By ~ 15

Author(s):

Gregory Grochola ◽

Salvy P. Russo ◽

Ian K. Snook ◽

Irene Yarovsky

Keyword(s):

Simulation Methods ◽

Free Energies ◽

Disordered Solids ◽

Interfacial Free Energies

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Quantitative Evaluation of the Interfacial Free Energies at A Solid-Liquid Lamellar Eutectic Interface

MRS Proceedings ◽

10.1557/proc-12-305 ◽

1981 ◽

Vol 12 ◽

Author(s):

W. F. Kaukler ◽

J. W. Rutter

Keyword(s):

Free Energy ◽

Solid Phase ◽

Interfacial Free Energy ◽

Eutectic System ◽

Liquid Interfaces ◽

Free Energies ◽

Two Phases ◽

Interfacial Free Energies ◽

The Individual ◽

Solid Liquid

The solid-liquid interfacial free energies of each of the individual phases comprising the eutectic system, Carbon Tetrabromide-Hexachloroethane, were measured as a function of composition using a “grain boundary groove” technique. Thermodynamic data were combined with groove shape measurements made from high resolution optical photomicrographs of the solid-liquid interfaces to give the interfacial free energy data. An interfacial free energy balance at the eutectic trijunction was performed to obtain all the forces acting on that point. The three interphase interfacial free energies at the eutectic trijunctions as well as a solid-solid phase boundary torque were evaluated.It was found that the solid-liquid interfacial free energies of the two phases of the eutectic could be evaluated from photomicrographs of growing or stationary eutectic interfaces. In addition, it was found that for a substantial range of freezing conditions the eutectic interface shape can be predicted from a knowledge of the interfacial free energies alone.

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Interfacial Free Energies and the Creep of Multilayer Thin Films

MRS Proceedings ◽

10.1557/proc-505-157 ◽

1997 ◽

Vol 505 ◽

Author(s):

D. Josell ◽

W. C. Carter

Keyword(s):

Thin Films ◽

New Technique ◽

Multilayer Thin Films ◽

Free Energies ◽

Creep Properties ◽

Multilayer Foils ◽

A New Technique ◽

Interfacial Free Energies

ABSTRACTExperiments utilizing the creep properties of multilayer thin films to determine interfacial free energies are presented with essential theory. A new technique utilizing tubular multilayer foils is then described.

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