13th International Conference on Fracture June 16–21, 2013, Beijing, China -5- Fig. 4.a shows the delamination region that was investigated by EBSD technique to obtaining of the microtexture. Fig. 4.b displays the orientation map, as well orientation triangle, where it can be observed a random grain sizes distribution from the rolling process occurred in the (α + γ) range, as also the higher predominance of <111> and <100> orientations. Also in Fig. 4.b displays the remaining points may be perlite regions, which have very fine lamella (about 200nm). As the distance between lamellas is smaller than the step size used, the occurrence to indexation of crystallographic planes to these regions was not possible, resulting in dark regions. Another plausible explanation is associated to the material deformation, which can contribute to the accumulation of dislocations at grain boundaries, resulting in non-indexed regions. Fig. 5 shows the Taylor factor distribution from the delamination region. It is possible to note the higher predominance of Taylor factor value between 2.5 to 3.5 corresponding 68% of grains. Moreover, 41% of grains have Taylor factor value lower 3 indicating lower absorbed energy. This indicates that the delamination phenomenon occur in the lower Taylor factor values. While the higher Taylor factor value (4) corresponded only 6% of grains. TD a) b) c) RD Figure 4. a) Delamination region used for microtexture analysis by EBSD technique b) orientation map of the selected region in the figure 3.a c) The Taylor factor Map of the same region.
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