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An Einstein Model of Brittle Crack Propagation

Brad Lee Holian·Raphael Blumenfeld·Peter Gumbsch
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Abstract

We propose a minimal nonlinear model of brittle crack propagation by considering only the motion of the crack-tip atom. The model captures many essential features of steady-state crack velocity and is in excellent quantitative agreement with many-body dynamical simulations. The model exhibits lattice-trapping. For loads just above this, the crack velocity rises sharply, reaching a limiting value well below that predicted by elastic continuum theory. We trace the origin of the low limiting velocity to the anharmonicity of the potential well experienced by the crack-tip atom.

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Brad Lee Holian, Raphael Blumenfeld, Peter Gumbsch. 1996-11-13. An Einstein Model of Brittle Crack Propagation. https://doi.org/10.1103/physrevlett.78.78

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