Numerical simulations of thermosolutal instability during directional solidification of a binary alloy

The paper deals with axial segregation in unsteady diffusion dominated directional solidification from melt of a binary alloy in a finite cylindrical ampoule. The study focuses on the influence of the finite length of the ampoule on the concentration profile in a crystal obtained in a microgravity environment. The results are compared to those reported by Kim et al. [J. Crystal Growth183, 490 (1998)] for an infinite crystal. Numerical simulations are performed for two different situations: the initial transient solidification when the melt is uniform in composition, and the multipass solidification when the crystal is grown from the melt, formed by re-melting a crystal with an initial axial composition profile.

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Effects of Coriolis and Centrifugal Forces on the Melt during Directional Solidification of a Binary Alloy

Materials Processing in High Gravity ◽

10.1007/978-1-4615-2520-2_14 ◽

1994 ◽

pp. 133-137 ◽

Cited By ~ 2

Author(s):

D. N. Riahi

Keyword(s):

Directional Solidification ◽

Binary Alloy ◽

Centrifugal Forces ◽

Coriolis And Centrifugal Forces

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Phase field modeling of shallow cells during directional solidification of a binary alloy

Journal of Crystal Growth ◽

10.1016/s0022-0248(01)01893-0 ◽

2002 ◽

Vol 237-239 ◽

pp. 138-143 ◽

Cited By ~ 26

Author(s):

Zhiqiang Bi ◽

Robert F. Sekerka

Keyword(s):

Directional Solidification ◽

Binary Alloy ◽

Phase Field ◽

Phase Field Modeling ◽

Field Modeling

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Directional solidification of a binary alloy into a cellular convective flow: localized morphologies

Journal of Fluid Mechanics ◽

10.1017/s0022112099005856 ◽

1999 ◽

Vol 395 ◽

pp. 253-270 ◽

Cited By ~ 8

Author(s):

Y.-J. CHEN ◽

S. H. DAVIS

Keyword(s):

Directional Solidification ◽

Binary Alloy ◽

Temporal Dynamics ◽

Three Dimensional ◽

Multiple Scale ◽

Solute Diffusion ◽

Two Dimensional ◽

Morphological Instability ◽

Flow Strength ◽

Weakly Nonlinear

A steady, two-dimensional cellular convection modifies the morphological instability of a binary alloy that undergoes directional solidification. When the convection wavelength is far longer than that of the morphological cells, the behaviour of the moving front is described by a slow, spatial–temporal dynamics obtained through a multiple-scale analysis. The resulting system has a parametric-excitation structure in space, with complex parameters characterizing the interactions between flow, solute diffusion, and rejection. The convection in general stabilizes two-dimensional disturbances, but destabilizes three-dimensional disturbances. When the flow is weak, the morphological instability is incommensurate with the flow wavelength, but as the flow gets stronger, the instability becomes quantized and forced to fit into the flow box. At large flow strength the instability is localized, confined in narrow envelopes. In this case the solutions are discrete eigenstates in an unbounded space. Their stability boundaries and asymptotics are obtained by a WKB analysis. The weakly nonlinear interaction is delivered through the Lyapunov–Schmidt method.

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Phase-field simulation of competitive growth of grains in a binary alloy during directional solidification

China Foundry ◽

10.1007/s41230-018-8020-7 ◽

2018 ◽

Vol 15 (5) ◽

pp. 333-342 ◽

Cited By ~ 1

Author(s):

Li Feng ◽

Ya-long Gao ◽

Ni-ni Lu ◽

Chang-sheng Zhu ◽

Guo-sheng An ◽

...

Keyword(s):

Directional Solidification ◽

Binary Alloy ◽

Phase Field ◽

Competitive Growth ◽

Phase Field Simulation ◽

Field Simulation

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Study on Microstructural Evolution of Binary Alloy Crystal Growth in Directional Solidification Process

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.470.100 ◽

2013 ◽

Vol 470 ◽

pp. 100-103

Author(s):

Dong Sheng Chen ◽

Ming Chen ◽

Rui Chang Wang

Keyword(s):

Crystal Growth ◽

Directional Solidification ◽

Binary Alloy ◽

Phase Field ◽

Field Model ◽

Phase Field Model ◽

Field Method ◽

Phase Field Method ◽

Pure Substance ◽

Columnar Dendrite

PFM (phase field method) was employed to study microstructure evolution, and considering the effect of solute concentration to the undercooling, we developed a phase field model for binary alloy on the basis of pure substance model. In the paper, the temperature field and solute field were coupled together in the phase field model to calculate the crystal growth of magnesium alloy in directional solidification. The simulation results showed a non-planar crystal growth of planar to cellular to columnar dendrite, the comparison of different dendrite patterns were carried out in the numerical simulation, and with the increasing of the anisotropy, the second dendrite arms became more developed.

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