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arXiv · 0809.1920

Hexagonal eutectic solidification patterns operating near a marginal stability point

Mikael Perrut·Silvère Akamatsu·Sabine Bottin-Rousseau·Gabriel Faivre
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Abstract

We study the long-time dynamics of hexagonal directional-solidification patterns in bulk samples of a transparent eutectic alloy using an optical method which permits real-time observation of the growth front. A slow dilatation of the patterns due to a slight curvature of the isotherms drives the system into a permanent regime, close to the threshold for the rod splitting instability. Thus an apparently minor instrumental imperfection suffices to maintain the system near a marginal stability point. This answers the long-standing question of spacing selection in bulk eutectic growth.

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Mikael Perrut, Silvère Akamatsu, Sabine Bottin-Rousseau, Gabriel Faivre. 2008-09-11. Hexagonal eutectic solidification patterns operating near a marginal stability point. https://arxiv.org/abs/0809.1920

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