Theory of Narrow U-Shaped Notches in Linear Fracture Mechanics

On the basis of linear fracture mechanics, a complete set of asymptotic formulas is obtained to describe the stress-strain state at the top of a narrow U-shaped notch. This type of defect can be possessed by a crack that has undergone a corrosive effect of the environment, or there can be a crack-like defect in a welded joint, e.g. lack of penetration, undercut, or a narrow slot in the part. To comparatively assess the risk of cracking at the tops of narrow U-shaped notches, and identify the places and directions of fracture initiation, we reveal the possibility of using such energy criteria as the deformation energy density and The previously indicated criteria were proposed by the author of this work for classical cracks-cuts. The purpose of this work was to study, on the basis of singular solutions of linear fracture mechanics, the stress-strain state in terms and near the tops of extremely narrow U-shaped notches, i.e., blunt cracks, in comparison with classical cracks-cuts

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