ORIENTATION CHANGES DURING ANNEALING OF NANOTRUCTURED ALUMINIUM

The annealing process of highly strained (epsilon=4.0) Al with a nano sized structure has been studied. The microstructural evolution during annealing was followed ex-situ by EBSD, and recrystallisation kinetics during annealing were measured in-situ by the 3DXRD technique. The present work aims to analyse the changes in crystallographic orientations during recovery and recrystallization. The EBSD data are used to quantify the texture after deformation and after annealing for various periods of times at 250 degrees C. It is shown that during the early stages of annealing, not much textural change occurs whereas a cube texture evolves and dominates after 20h at 250 degrees C. The EBSD data further reveal that the largest grains have a preference for a cube orientation. The 3DXRD data are used for an analysis of recovering and recrystallizing grains. Significant differences between the 2 groups are observed.