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arXiv · 1210.7218

A Phase Field Crystal Study of Solute Trapping

Harith Humadi·Jeffrey J. Hoyt·Nikolas Provatas
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Abstract

In this study we have incorporated two time scales into the phase field crystal model of a binary alloy to explore different solute trapping properties as a function of crystal-melt interface velocity. With only diffusive dynamics, we demonstrate that the segregation coefficient, K as a function of velocity for a binary alloy is consistent with the model of Kaplan and Aziz where K approaches unity in the limit of infinite velocity. However, with the introduction of wave like dynamics in both the density and concentration fields, the trapping follows the kinetics proposed by S. Sobolev[Phys. Rev. A. 199:383386, 1995.], where complete trapping occurs at a finite velocity.

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Harith Humadi, Jeffrey J. Hoyt, Nikolas Provatas. 2012-10-26. A Phase Field Crystal Study of Solute Trapping. https://doi.org/10.1103/physreve.87.022404

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