Abstract: The distributions of the stress， strain and slip systems in pure copper foil rolling with the same reduction were simulated by the rate-dependent crystal plasticity theory and Voronoi polycrystalline model with respect to specimen dimension， grain orientation and its distribution to quantitatively evaluate the influence of thickness on inhomogeneous deformation behavior of foil rolling at mesoscale. The simulated stress-strain curves agree well with the experimental results. The simulation results reveal that the deformation behavior in the polycrystalline aggregate is inhomogeneous not only in intracrystalline but also in intergranule with a 20% reduction in foil rolling. The foils are composed of only a single layer grain across thickness， the grains with different sizes， shapes and orientations are unevenly distributed in the foil， the misorientation of neighboring grains and the property of active slip systems.

Key words: foil rolling, crystal plasticity finite element, inhomogeneous deformation, slip system activity