Dislocation core field. I. Modeling in anisotropic linear elasticity theory

TL;DR

This paper models the dislocation core field within anisotropic linear elasticity, deriving energy expressions and interaction forces, highlighting the core field's role in dislocation behavior under stress gradients.

Contribution

It introduces a comprehensive model of the dislocation core field in anisotropic elasticity, including energy and interaction contributions, which were not previously fully characterized.

Findings

Core field contributes to dislocation interaction energy with external stress.

No cross term exists between Volterra and core fields in elastic energy.

Core field induces a force proportional to stress gradient, relevant near crack tips.

Abstract

Aside from the Volterra field, dislocations create a core field, which can be modeled in linear anisotropic elasticity theory with force and dislocation dipoles. We derive an expression of the elastic energy of a dislocation taking full account of its core field and show that no cross term exists between the Volterra and the core fields. We also obtain the contribution of the core field to the dislocation interaction energy with an external stress, thus showing that dislocation can interact with a pressure. The additional force that derives from this core field contribution is proportional to the gradient of the applied stress. Such a supplementary force on dislocations may be important in high stress gradient regions, such as close to a crack tip or in a dislocation pile-up.