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Crack Tip Relaxation Governs Onset of Fracture Instability

Farid F. Abraham
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Abstract

A dynamic crack will travel in a straight path up to a material-dependent critical speed beyond which its path becomes erratic. Predicting this critical speed and discovering the origin of this instability are two outstanding problems in fracture mechanics. We recently discovered a simple scaling model based on an effective elastic modulus that gives successful predictions for this critical speed by transforming the nonlinear crack dynamics problem into a linear elasticity representation. We now show that a simple atomic picture based on broken-bond relaxation at the dynamic crack tip provides an explanation for the origin of the effective elastic modulus.

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Farid F. Abraham. 2006-11-09. Crack Tip Relaxation Governs Onset of Fracture Instability. https://doi.org/10.2174/1874158400701010038

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