Analysis of cracks in the fields of elastic stresses from wedge disclinations

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Abstract

The article is devoted to the development of mathematical methods for analyzing cracks that occur in polycrystalline solids under the action of stress fields created by wedge disclinations. A method is proposed for calculating the main crack characteristics, such as the density of the Burgers vector of virtual dislocations, stress intensity factors at the crack tips, and the crack faces opening function, for an arbitrary disclination location. The method is based on replacing the solution for the initial disclination with a superposition of the solution for the disclination with a known analytical expression and the solution for a continuous wall of edge dislocations. As a result of applying this method, exact analytical expressions are obtained for the specified parameters in the case where the disclination is located on the crack axis, as well as asymptotic expressions for the stress intensity factors of the crack in the elastic field created by the disclination located near the tip. A comparative analysis of dislocation and disclination cracks is carried out, revealing their fundamental difference: when entering a crack, a dislocation is spread out in the form of a distribution of virtual dislocations along the crack and ceases to exist as a localized defect. In contrast, the disclination remains as an independent source of stress, which is only partially screened by virtual dislocations. The fields of elastic stresses from a disclination crack are calculated, the influence of the disclination position on its interaction with the lattice dislocation is analyzed. It was found that the dependence of the interaction force on the distance between the lattice dislocation and the crack tip is alternating and non-monotonic nature. The results of the study are valuable for developing methods for predicting fracture in materials obtained by severe plastic deformation.

Keywords

disclinationcrackstress intensity factorsdislocationelastic stress fieldssevere plastic deformationfracture.

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Article information

Published
17 December 2025
Issue date
17 December 2025
Issue
No. 5 (2025)
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