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Crossover Scaling of Wavelength Selection in Directional Solidification of Binary Alloys

Michael Greenwood·Mikko Haataja·Nikolas Provatas
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Abstract

We simulate dendritic growth in directional solidification in dilute binary alloys using a phase-field model solved with an adaptive-mesh refinement. The spacing of primary branches is examined for a range of thermal gradients and alloy compositions and is found to undergo a maximum as a function of pulling velocity, in agreement with experimental observations. We demonstrate that wavelength selection is unambiguously described by a non-trivial crossover scaling function from the emergence of cellular growth to the onset of dendritic fingers, a result validated using published experimental data.

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Michael Greenwood, Mikko Haataja, Nikolas Provatas. 2004-03-21. Crossover Scaling of Wavelength Selection in Directional Solidification of Binary Alloys. https://doi.org/10.1103/physrevlett.93.246101

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