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arXiv · 1710.06004

Nonlinear focusing in dynamic crack fronts and the micro-branching transition

Itamar Kolvin·Jay Fineberg·Mokhtar Adda-Bedia
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Abstract

Cracks in brittle materials produce two types of generic surface structures: facets at low velocities and micro-branches at higher ones. Here we observe a transition from faceting to micro-branching in polyacrylamide gels that is characterized by nonlinear dynamic localization of crack fronts. To better understand this process we derive a first-principles nonlinear equation of motion for crack fronts in the context of scalar elasticity. Its solution shows that nonlinear focusing coupled to rate-dependence of dissipation governs the transition to micro-branching.

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Itamar Kolvin, Jay Fineberg, Mokhtar Adda-Bedia. 2017-10-16. Nonlinear focusing in dynamic crack fronts and the micro-branching transition. https://doi.org/10.1103/physrevlett.119.215505

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