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The anisotropic mechanical response of f.c.c. metals deformed up to large
strains at low homologous temperatures is controlled by interfaces, namely
by fragment and grain boundaries. The proposed model starts from initial
grain orientations and the corresponding slip rates as predicted by a full
constraints (FC) Taylor code. It describes the cell structure development
on the microscopic scale and the fragment structure development on the
mesoscopic scale in terms of evolution equations for dislocation densities
in the twelve f.c.c. slip systems and for disclination densities in six
fragment boundary families, respectively. The redundant dislocation
densities (or: the cell walls) and the immobile disclination densities and
powers (or: the fragment boundary triple junctions) are connected to critical
resolved shear stress (CRSS) contributions. Thus, substructure and texture
evolution as well as the resulting macroscopic mechanical behaviour are
coupled to each other. Results for several initial grain orientations are
presented and compared to experimental observations.
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