Results pertaining to the formation and dynamics of planar dislocation boundaries in deformed face-centered cubic single crystals using a multi-scale analysis were presented. A pure tilt boundary and experimentally observed extended geometrically necessary boundaries were constructed within the representative volume element for multi-scale simulations. The model couples discrete dislocation dynamics analysis with continuum finite element to correct for the boundary conditions and image stress. It was shown that the right boundary condition of the representative volume element was critical in modeling geometrically necessary boundaries and their long-range stresses. The effects of various numerical factors, such as domain length and mesh sensitivity, were also considered. The effect of changing the spacing, between 2 dislocation boundaries, upon the self-stress field and the stability, particularly in the space between the 2 dislocation boundaries, was presented. Relaxed configurations using dislocation dynamics revealed the formation of a uniform network which was stabilized by the formation of junctions and dipoles.

Modeling Planar Dislocation Boundaries using Multi-Scale Dislocation Dynamics Plasticity. S.M.A.Khan, H.M.Zbib, D.A.Hughes: International Journal of Plasticity, 2004, 20[6], 1059-92