Strongly Developed Texture Components near Rotated Cube Orientation during Recrystallization in a Severely Cold Rolled Low Carbon Steel

抄録

Extraordinarily strong recrystallization texture components near rotated cube ({100}<011>) developed in a low carbon steel processed with a severe cold rolling at 99.8% reduction followed by an annealing at 550°C or more. The rotated cube orientation is beneficial for magnetic applications, while it has been recognized as an orientation difficult to recrystallize. Unlike the conventional 90% cold rolling sample, the 99.8% cold rolling sample showed an unusually strong α fiber deformation texture and a fine lamellar structure understood from previous work to be generated via grain subdivision. In addition, texture analysis of a partially recrystallized sample at lower temperature anneal of 450°C revealed that the {100}<0 7 10> oriented grains recrystallized discontinuously from near the domain boundaries in the 99.8% cold rolled sample, while the {100}<011> oriented grains were likely to recrystallize continuously. Kernel average misorientation analysis of EBSD data suggested that the {100}<011> oriented grains underwent a faster recovery than the other α fiber orientations, resulting in a fast nucleation and growing toward the deformed matrix. Since this oriented nucleation of {100}<011> oriented grains was not observed in 99.8% cold rolled pure iron and 99.2% cold rolled interstitial free steel, solute carbons in the steel would play a significant role for the selective and fast recovery of the {100}<011> oriented grains during the annealing process.

(a) Enlarged view of the squared area in Fig. 7(a). The misorientation angle more than 5° are indicated in black line. (b) Distribution of misorientation angle from {100}<011> orientation along the arrow in (a). (c) {110} Pole figure corresponding to the 6 orientations along the arrow in (a). (d) Schematic illustration of new boundary formation during a severe cold rolling.