STRAIN GRADIENT POLYCRYSTAL PLASTICITY ANALYSIS: FE MODELING AND SYNCHROTRON X-RAY DIFFRACTION

The results of a strain gradient finite element model of polycrystalline plastic deformation in an HCP alloy were analysed in terms of orientation-related meso-scale grain groups. The predictions for meso-scale elastic strains were post-processed to construct energy dispersive diffraction peak patterns. Synchrotron X-ray polycrystalline diffraction was thereafter employed to record experimentally multiple peaks from deformed samples of Ti-6Al-4V alloy. Model parameters were adjusted to provide the best simultaneous match to multiple peaks in terms of intensity, position and shape. The framework provides a rigorous means of validating polycrystal plasticity finite element model. The study represents an example of the parallel development of modelling and experimental tools that is useful for the study of statistically stored dislocations (SSDs) and geometrically necessary dislocations (GNDs) effects on the deformation behaviour of (poly)crystals.