Papers by Keyword: Misorientation Distribution Function

Abstract: The microstructure and texture evolutions in pure titanium during severe plastic deformation at T=400°C were investigated. Compressive deformation of prismatic samples was sequentially applied in three orthogonal directions up to 12 steps and a strain at each step of 40%. A radical microstructure refinement (from 20 to 0.2 µm) during strain has been found. The features of the deformation structure are a high level of internal stresses, high density of dislocations, a large number of deformation induced boundaries and the presence of twins. It is shown that during strain there is a significant change in disorientation angles and axes of individual high angle grain boundaries. At the same time the total set of high angle boundaries - Misorientation Distribution Function (MDF) and texture - does not change significantly with strain. The reasons for the change in disorientation angles and axes at new deformation-induced boundaries during plastic flow are discussed.

Abstract: A Fe-2.8%Si single crystal was scratched in order to randomise the texture in the neighbourhood of the notch. Annealing resulted in recrystallization and grain growth starting from the deformed zone. Misorientations between the single crystal matrix and the grown grains were gathered and were studied in order to investigate the possibility for selective growth based on a specific misorientation. However, instead of studying the misorientation angle or axis profiles separately in a 1D or 2D projection a full misorientation analysis was carried out in the 3-dimensional Rodrigues-Frank misorientation space, which offers an unambiguous interpretation of the data because no features are hidden or masked by a projection. It is concluded that the selective growth phenomenon following the <110>26.5deg misorientation relationship is strongly supported by the gathered orientation data, after appropriately normalizing these data with respect to a random misorientation distribution.