A quantitative investigation of the peculiarities of fracture of the metal ahead of notch and sharp crack has been performed on a basis of the statistical model of mi-crocrack nucleation and growth in polycrystalline metal developed by author. These peculiarities are associated with scale effect, influence of local plastic strain on fracture probability and effect of triaxial tension on the value of the local fracture stress. It is shown that the influence of local small plastic strain on the susceptibility of the fracture stress to a "process zone" volume is a specific feature of the scale effect in metal. The results show that there is a need to predict brittle fracture of notched specimens over a wide temperature region (from small-scale yielding to general yielding) to incorporate the effect of small plastic strain. All these effects have been expressed in terms of Weibull parameters. It is shown that these parameters aren't material constants, and they depend on the plastic strain and stress state ahead of a notch.
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