A multiple-slip dislocation-density based model was coupled with a kinematically based scheme that accounted for grain-boundary interfacial interactions with dislocation densities. Finite-element methods were used to gain a detailed understanding of the initiation and evolution of large inelastic deformation modes due to mechanisms that could result from dislocation-density pile-ups at grain-boundary interfaces, partial and total dislocation-density transmission from one grain to a neighboring grain and dislocation-density absorption within grain boundaries. These techniques could be used to understand how interactions at the grain-boundary interface scale affected the overall macroscopic behavior at various inelastic stages of the deformation of polycrystalline aggregates due to the interrelated effects of grain-boundary orientation, evolution of mobile and immobile dislocation densities, slip-system orientation, strain hardening, geometrical softening, geometrical slip compatibility and localized plastic strains. Criteria were developed for identifying and monitoring the initiation and evolution of multiple regions where dislocation pile-ups at grain-boundaries, partial and total dislocation

density transmission through the grain-boundary or absorption within the grain-boundary could occur.

Prediction of Grain-Boundary Interfacial Mechanisms in Polycrystalline Materials. W.M.Ashmawi, M.A.Zikry: Journal of Engineering Materials and Technology, 2002, 124[1], 88-96