13th International Conference on Fracture June 16–21, 2013, Beijing, China -9- 3 1 2 TD RD 4 5 6 Figure 9. Mapping of Taylor Factor a) Scanned region, b) Histogram of number fractions 4. Conclusions Charpy impact testing showed that specimens with L-T orientation absorbed more energy than specimens with T-L orientation. It was observed two types of delaminations during fracture process, the crack arrester-type delamination and crack divider-type delamination. The first type propagates parallel to the notch, while the second propagates perpendicular to notch. Crack arrester-type delamination tends to increase upper shelf energy during Charpy impact testing, and both types of delaminations tend to disappear with decreasing temperature. The results obtained by EBSD technique shows the propagation mode of a crack generated by a divider-type delamination was intergranular. The main microtexture components obtained in the perpendicular region to the direction of fracture propagation from ODF were (221) [1-10] (223) [1-10] (112) [1-3 -2] and (332) [023] orientations. While in the parallel region to the direction of fracture propagation the (223) [0-32] and (332) [1-10] orientations were the main microtexture components. The Taylor factor analysis display the difference in the Taylor factor values with crystallographic orientation, as expected. It was also observed the presence of the (100) planes and Taylor factor value close to 2.7 in the respective regions investigated, consequently, a smaller stored energy was observed. This confirms the fracture mechanisms from the delaminations are given by little plastic deformation, namely, brittle fracture. a) b)
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