Dislocation density-based evolution formulations that were related to a heterogeneous microstructure and were physically representative of different crystalline interactions were developed. The balance between the generation and annihilation of dislocations, through glissile and forest interactions at the slip system level, was taken as the basis for the evolution of mobile and immobile dislocation densities. The evolution equations were coupled to a multiple slip crystal plasticity formulation, and a framework was established that related it to a general class of crystallographies and deformation modes. Specialized finite element methodologies had then been used to investigate how certain dislocation density activities, such as dislocation density interactions and immobilization, were directly related to strain hardening and microstructure evolution. The predictions were validated with channel die compressed experiments, and were consistent with inelastic deformation modes of face-centered cubic metals.

Dislocation Density Evolution and Interactions in Crystalline Materials. P.Shanthraj, M.A.Zikry: Acta Materialia, 2011, 59[20], 7695-702