On Goss Orientation in Strip Cast Grain-Oriented Silicon Steel

In this study, the origin of Goss texture during intermediate annealing and Goss texture development during secondary annealing of strip cast grain-oriented silicon steel are studied by electron backscattered diffraction (EBSD). The study indicates that Goss grains originate inside the shear bands of deformed {111}<112> and {111}<110> grains. Compared to {111}<110> grains, {111}<112> grains provide more number of nucleation sites for Goss grains. During subsequent recrystallization process, Goss grains exhibit a smaller growth rate than the average value of all the recrystallized grains. The development mechanism of Goss texture is concluded as oriented nucleation. Prior to secondary annealing, high fraction of high-energy boundaries (20 degrees-45 degrees misorientation angle) are observed in the vicinity of Goss grains, while significantly low fraction of Sigma 5 + Sigma 7 + Sigma 9 boundaries are observed. During secondary annealing, the domination of high energy boundaries around Goss grains is maintained, but the fraction of Sigma 5 + Sigma 7 + Sigma 9 boundaries decrease to be similar to the matrix grains. After the onset of the abnormal grain growth, the growing Goss grains continue to consist of high fraction of high-energy boundaries. These results are consistent with the high energy (HE) boundary model, which is used to explain the abnormal grain growth in the current strip casting route.