The backstress effect of evolving deformation boundaries in FCC polycrystals

Shape change of metal systems generates deformed microstructures of dislocation arrays that are comprised of walls of high density separating low density cells. The flow stresses of these composite structures are equilibrated by an evolving internal stress due to the blockage of dislocation passage resulting in kinematic hardening in the meso-scale. The method of intra-granular backstress of Eshelby using Kröner based approach in closed form formulae can easily be incorporated into a crystal-plasticity-based model to predict the kinematic hardening. We have previously developed finite element analyses based on the rate dependent crystal plasticity theory, which can incorporate electron backscatter diffraction (EBSD) maps. We will use this model with inclusion of the calculated backstress to investigate the effect of changes in strain paths.