Characterization and modeling of heterogeneous deformation in commercial purity titanium

Abstract

Heterogeneous deformation, including local dislocation shear activity and lattice rotation, was analyzed in microstructure patches of polycrystalline commercial purity titanium specimens using three different experimental methods. The measurements were compared with crystal plasticity finite element simulations for the same region that incorporate a local phenomenological hardening constitutive model. The dislocation activity was measured using techniques associated with atomic force microscopy, confocal microscopy, three-dimensional x-ray diffraction, and nano-indentation. The results indicate that a major challenge for model development is to effectively predict conditions where slip transfer occurs, and where geometrically necessary dislocations accumulate.