Author(s): Donald Carter
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Keywords: No Keywords
Abstract: The dislocation pile-up model of Stroh has been used to study crack nucleation. By energy balance considerations, the author has derived the brittle fracture criteria for both tensile and compressive tests. For an uniaxial tensile load, the stress required for crack propagation is smaller than the nucleation stress; once nucleated the crack will be self-propagating with respect to the applied stress. For an uniaxial compressive load, once nucleated the crack will come to rest at a finite length. By considering the energy dissipated in the plastic region at the head of this stable crack, it has been shown that when unstable quasi-brittle fracture occurs under compressive stress, the ratio of brittle fracture stress to maximum ductile stress is 0.6. This analysis both predicts and provides a physical interpretation of the observed features of snow ice brittle behavior.
Year: 1970