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arXiv · 2003.13805

Effective toughness of heterogeneous materials with rate-dependent fracture energy

Gabriele Albertini·Mathias Lebihain·François Hild·Laurent Ponson·David S. Kammer
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Abstract

We investigate dynamic fracture of heterogeneous materials experimentally by measuring displacement fields as a rupture propagates through a periodic array of obstacles of controlled fracture energy. Our measurements demonstrate the applicability of the classical equation of motion of cracks at a discontinuity of fracture energy: the crack speed jumps at the entrance and exit of an obstacle, as predicted by the crack-tip energy balance within the brittle fracture framework. The speed jump amplitude is governed by the fracture energy contrast and by the combination of rate-dependency of fracture energy and inertia of the medium, which allows the crack to cross a fracture energy discontinuity at constant energy release rate. This discontinuous dynamics and the rate-dependence cause higher effective toughness, which governs the coarse-grained behavior of these cracks.

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Gabriele Albertini, Mathias Lebihain, François Hild, Laurent Ponson, David S. Kammer. 2021-06-28. Effective toughness of heterogeneous materials with rate-dependent fracture energy. https://doi.org/10.1103/physrevlett.127.035501

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