On the continuum formulation of higher-gradient plasticity for single and polycrystals (Q1578524)

The authors develop a geometrically linear formulation of higher-gradient plasticity of single and polycrystalline materials based on continuum theory of dislocations and incompatibilities. A phenomenological physically motivated description of hardening is obtained, which incorporates into the yield condition for single crystals second-order spatial derivatives of plastic deformation gradient, and for polycrystals fourth-order spatial derivatives of plastic strain . Thus, in the kinematic hardening the backstress obeys a nonlocal evolution law. An example is given.