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arXiv · 1505.04275

Crack front dynamics: the interplay of singular geometry and crack instabilities

Itamar Kolvin·Gil Cohen·Jay Fineberg
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Abstract

When fast cracks become unstable to microscopic branching (micro-branching), fracture no longer occurs in an effective 2D medium. We follow in-plane crack front dynamics via real-time measurements in brittle gels as micro-branching unfolds and progresses. We first show that {\em spatially local} energy balance quantitatively describes crack dynamics, even when translational invariance is badly broken. Furthermore, our results explain micro-branch dynamics; why micro-branches form along spatially localized chains and how finite-time formation of cusps along the crack front leads to their death.

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Itamar Kolvin, Gil Cohen, Jay Fineberg. 2015-05-16. Crack front dynamics: the interplay of singular geometry and crack instabilities. https://doi.org/10.1103/physrevlett.114.175501

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