A number of studies have directly compared measurements of polycrystals’
deformation to the solution of a crystal plasticity model of the same polycrystal. An
accurate representation of the full 3D microstructure and the boundary conditions
has been shown to be important to obtain a good correspondence between the
behaviour of the real and the simulated polycrystal. However, much less is known
about the relationship between the global and the local solutions of crystal plasticity
models and the influence of material parameters on the local response of the
polycrystal. To address these questions, uncertainty quantification and sensitivity
analysis are performed on finite element models of oligocrystals with a crystal
plasticity material model. The results show significant variations in the simulated
stress and strain fields due to variations in the material parameters. Sensitivity
analysis is used to quantify the contribution of crystal orientation, latent
hardening and other material model parameters to the variability of the
crystal plasticity finite element model solution. The uncertainty in the stress
and strain fields and their sensitivities vary between the oligocrystals, but
nevertheless, some distinct trends can be identified. The most prominent trend is
that, in general, the solution is most sensitive to the variations of the latent
hardening description and the crystallographic orientations of the constituent
crystals.