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arXiv · 1506.08882

Segregation-induced phase transformations in grain boundaries

Timofey Frolov·Mark Asta·Yuri Mishin
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Abstract

Phase transformations in metallic grain boundaries (GBs) present significant fundamental interest in the context of thermodynamics of low-dimensional physical systems. We report on atomistic computer simulations of the Cu-Ag system that provide direct evidence that GB phase transformations in a single-component GB can continue to exist in a binary alloy. This gives rise to segregation-induced phase transformations with varying chemical composition at a fixed temperature. Furthermore, for such transformations we propose an approach to calculations of free energy differences between different GB phases by thermodynamic integration along a segregation isotherm. This opens the possibility of developing quantitative thermodynamics of GB phases, their transformations to each other, and critical phenomena in the future.

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Timofey Frolov, Mark Asta, Yuri Mishin. 2015-06-29. Segregation-induced phase transformations in grain boundaries. https://arxiv.org/abs/1506.08882

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