Dissipative Visco-plastic Deformation in Dynamic Fracture: Tip Blunting and Velocity Selection

Abstract

Dynamic fracture in a wide class of materials reveals "fracture energy" $\Gamma$ much larger than the expected nominal surface energy due to the formation of two fresh surfaces. Moreover, the fracture energy depends on the crack velocity, $\Gamma =\Gamma (v)$. We show that a simple dynamical theory of visco-plasticity coupled to asymptotic pure linear-elasticity provides a possible explanation to the above phenomena. The theory predicts tip blunting characterized by a dynamically determined crack tip radius of curvature. In addition, we demonstrate velocity selection for cracks in fixed-grip strip geometry accompanied by the identification of $\Gamma$ and its velocity dependence.

arXiv comment4 pages, 1 figures; presentation improved, refs. changed, figure omitted

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Cited by in corpus (6)

• Locality and Non-locality in Elasto-plastic Responses of Amorphous Solids
• Oscillatory Instability in Two-Dimensional Dynamic Fracture
• Dynamic Failure in Amorphous Solids via a Cavitation Instability
• The Stability of an Expanding Circular Cavity and the Failure of Amorphous Solids
• Non-Affine Displacements and the Non-Linear Response of a Strained Amorphous Solid
• Free-Boundary Dynamics in Elasto-plastic Amorphous Solids: The Circular Hole Problem