Recrystallization boundary migration in the 3D heterogeneous microstructure near a hardness indent

Boundary migration during recrystallization in the heterogeneous microstructure near a hardness indent in lightly rolled pure Al was followed in 3D. The microstructure after multiple steps of ex-situ annealing was examined using synchrotron white-beam differential-aperture X-ray microscopy, supplemented by scanning electron microscopy. Heterogeneous recrystallization boundary migration was observed and analyzed in terms of driving force and boundary characteristics. The results reveal very similar local stored energies and boundary misorientations for the migrating and stationary boundary segments, whereas the grain boundary normals differ significantly. Effects of grain boundary mobility and deformation microstructure morphology on the migration are discussed. [Display omitted]