A microstructural study of the origins of γ recrystallization textures in 75% warm rolled IF steel

Abstract IF steel was warm rolled at 700 °C in a single pass. The resulting texture and microstructure were remarkably similar to those of the same steel after cold rolling. A detailed investigation of the microstructure by orientation imaging microscopy and scanning transmission electron microscopy showed microbands to have a mutual misorientation of less than 4° and shear bands to contain material misoriented from the parent matrix by less than 10°. Recrystallization did not occur preferentially at high-angle grain boundaries nor in shear bands. Instead the recrystallization nuclei were confined in the original hot band grain envelopes in crystals belonging to the γ fiber. These γ deformed grains had systematically developed deformation bands which consisted of elements that had rotated by up to ∼30° about the 〈1 1 1〉 parallel to the normal direction. This is essentially the same nucleation process as observed in cold rolled and annealed IF steel.