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arXiv · 0911.1233

Weakly faceted cellular patterns versus growth-induced plastic deformation in thin-sample directional solidification of monoclinic biphenyl

Tamas Borzsonyi·Silvere Akamatsu·Gabriel Faivre
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Abstract

We present an experimental study of thin-sample directional solidification (T-DS) in impure biphenyl. The plate-like growth shape of the monoclinic biphenyl crystals includes two low-mobility (001) facets and four high-mobility {110} facets. Upon T-DS, biphenyl plates oriented with (001) facets parallel to the sample plane can exhibit either a strong growth-induced plastic deformation (GID), or deformation-free weakly faceted (WF) growth patterns. We determine the respective conditions of appearance of these phenomena. GID is shown to be a long-range thermal-stress effect, which disappears when the growth front has a cellular structure. An early triggering of the cellular instability allowed us to avoid GID and study the dynamics of WF patterns as a function of the orientation of the crystal.

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Tamas Borzsonyi, Silvere Akamatsu, Gabriel Faivre. 2009-11-06. Weakly faceted cellular patterns versus growth-induced plastic deformation in thin-sample directional solidification of monoclinic biphenyl. https://arxiv.org/abs/0911.1233

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