Effect of solid–liquid interface velocity on the measured upper and lower limits of the liquidus temperature of cobalt–carbon eutectic fixed points

In this work, parallel molecular dynamics simulation is conducted to study the long-time (up to 2 ns) behavior of argon crystal in surface-nanostructuring with laser-assisted STM. A large system consisting of more than one hundred million atoms is explored. The study is focused on the solidification procedure after laser irradiation, which is driven by heat conduction in the material. Epitaxial re-growth is observed in the solidification. Atomic dislocation due to thermal strain-induced structural damages is observed as well in the epitaxial re-growth. During solidification, the liquid is featured with decaying normal compressive stresses and negligible shear stresses. Two functions are designed to capture the structure and distinguish the solid and liquid regions. These functions work well in terms of reflecting the crystallinity of the material and identifying the atomic dislocations. The study of the movement of the solid-liquid interface reveals an accelerating velocity in the order of 3~5 m/s. The spatial distribution of the solid-liquid interface velocity indicates a non-uniform epitaxial re-growth in space. The bottom of the liquid solidifies slower than that at the edge.

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Erratum: “Solid–liquid interface velocity and diffusivity in laser-melt amorphous silicon” [Appl. Phys. Lett. 77, 2337 (2000)]

Applied Physics Letters ◽

10.1063/1.1349865 ◽

2001 ◽

Vol 78 (19) ◽

pp. 2988-2988

Author(s):

Luigi Brambilla ◽

Luciano Colombo ◽

Vittorio Rosato ◽

Fabrizio Cleri

Keyword(s):

Amorphous Silicon ◽

Interface Velocity ◽

Liquid Interface ◽

Solid Liquid Interface ◽

Solid Liquid

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Processing/Microstructure Relationships in Surface Melting

MRS Proceedings ◽

10.1557/proc-13-733 ◽

1982 ◽

Vol 13 ◽

Cited By ~ 2

Author(s):

R. J. Schaefer ◽

R. Mehrabian

Keyword(s):

Rapid Solidification ◽

Interface Velocity ◽

Surface Melting ◽

Liquid Interface ◽

Flow Models ◽

Prediction And Control ◽

Beam Surface ◽

Solid Liquid Interface ◽

Solid Liquid ◽

And Control

ABSTRACTThe development of predictive models for rapid surface melting and resolidification requires coupling of realistic heat flow models to emerging theories of rapid solidification processing. Attainment of unique microstructures and phases,for example through plane-front solidification and solute trapping, can be correlated to solid/liquid interface velocity,temperature and temperature gradients, and to theories of morphological stability. However, there are important limitations on achievable solid/liquid interface velocity depending upon the heating mode and heat flux distribution,melt thickness and location of the interface within the molten zone.An overview is given of the emerging guidelines for prediction and control of rapid solidification conditions and microstructures. Homogenization of the liquid by convection and diffusion is also discussed. Electron beam surface melting of alloy substrates is used as an example of these processes.

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An analytical solution of the critical interface velocity for the encapturing of insoluble particles by a moving solid/liquid interface

Metallurgical and Materials Transactions A ◽

10.1007/s11661-998-0186-y ◽

1998 ◽

Vol 29 (1) ◽

pp. 351-358 ◽

Cited By ~ 51

Author(s):

J. K. Kim ◽

P. K. Rohatgi

Keyword(s):

Analytical Solution ◽

Interface Velocity ◽

Liquid Interface ◽

Insoluble Particles ◽

Solid Liquid Interface ◽

Solid Liquid

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Modeling of Nonequilibrium Surface Melting and Resolidification for Pure Metals and Binary Alloys

Journal of Heat Transfer ◽

10.1115/1.2822593 ◽

1996 ◽

Vol 118 (4) ◽

pp. 944-951 ◽

Cited By ~ 20

Author(s):

G.-X. Wang ◽

E. F. Matthys

Keyword(s):

Interface Velocity ◽

Surface Melting ◽

Liquid Interface ◽

Solute Diffusion ◽

High Heat Flux ◽

Slow Kinetics ◽

Pure Metals ◽

Velocity Variations ◽

Solid Liquid Interface ◽

Solid Liquid

A model was developed for surface melting and resolidification of both pure metal and binary alloy substrates. Nonequilibrium kinetics are introduced in the model to account for the departure from thermodynamic equilibrium at the solid/liquid interface. The modeled problem involves a moving boundary with both heat and solute diffusion and is solved by an implicit control volume integral method with solid/liquid interface immobilization by coordinate transformation. To illustrate the model capabilities, we have analyzed laser-induced surface melting of pure metals (Al, Cu, Ni, Ti) and dilute Al–Cu alloys, and some typical results are presented. The computation results show some large solid overheating and melt undercooling effects, which result from the high heat flux and the slow kinetics. Large interface velocity variations are also seen during the process, depending on the substrate material and laser flux. Complex interface velocity variations during the earlier stages of resolidification were also predicted for the alloys, and result from interactions between the several physical mechanisms involved. Results on interface temperatures, solute concentrations, and nonequilibrium partition coefficients are also presented.

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