In order to elucidate the formation of Goss grains after transverse cold rolling in a grain oriented silicon steel, computer color mapping was performed by using orientation information of Kossel diffraction patterns taken in advance in the recrystallized grains.
For computer color mapping in the vicinity of the steel surface after first stage cold rolling in the transverse direction and the subsequent intermediate annealing, the formation of Goss grains is very scarce and the size of these primary grains is much larger than that after a first straight cold rolling. Also, for similar computer color mappings after a second stage cold rolling in the transverse direction and the subsequent decarburization and primary recrystallization annealing, the formation of Goss grains is strongly inhibited. This inhibition has a decisive influence in conjunction with the cold rolling directions in the first and second stages; the previously generated Goss grains disappear by the transverse cold rolling. The preferential formation and inheritance of the celebrated Goss nuclei, which can be inherited by the structure memory from the original hot rolled silicon steel, are considered to be accomplished in cold rolling parallel to the hot rolling direction.
The Iron and Steel Institute of Japan