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On the role of confinement on solidification in pure materials and binary alloys

Badrinarayan P. Athreya·Jonathan A. Dantzig·Shan Liu·Rohit Trivedi
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Abstract

We use a phase-field model to study the effect of confinement on dendritic growth, in a pure material solidifying in an undercooled melt, and in the directional solidification of a dilute binary alloy. Specifically, we observe the effect of varying the vertical domain extent ($δ$) on tip selection, by quantifying the dendrite tip velocity and curvature as a function of $δ$, and other process parameters. As $δ$ decreases, we find that the operating state of the dendrite tips becomes significantly affected by the presence of finite boundaries. For particular boundary conditions, we observe a switching of the growth state from 3-D to 2-D at very small $δ$, in both the pure material and alloy. We demonstrate that results from the alloy model compare favorably with those from an experimental study investigating this effect.

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Badrinarayan P. Athreya, Jonathan A. Dantzig, Shan Liu, Rohit Trivedi. 2006-06-14. On the role of confinement on solidification in pure materials and binary alloys. https://doi.org/10.1080/14786430500157060

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