Evolution of Goss Orientation during Rapid Heating for Primary Recrystallization in Grain-oriented Electrical Steel

Abstract

To obtain ideal Goss-oriented Fe-3.1%Si electrical steel, we studied the Goss orientation and microstructure during the various processes from hot-band annealing to the primary recrystallization. In particular, we examined the effect of the heating rate (20 degrees C/s and 150 degrees C/s) on the primary recrystallization behavior. In the annealed hot-band, the surface and middle layers have different textures. In the surface layer, a weak Goss texture developed, while in the inner layer, very strong a-fiber and weak gamma-fiber texture were formed. The cold-rolled sheet had a relatively strong alpha-fiber and weak gamma-fiber texture. In the cold-rolled sheet, the Goss oriented grains with an average size of 0.15 mu m were more in the surface layer than in the middle layer. One part of the Goss-oriented grains originated from the annealed hot-band, while the other was formed during the cold rolling. During recrystallization, the size of the Goss-oriented grains was not influenced by the heating rate. However, the fraction and distribution of the grains depended on the heating rate. For high heating rates, the fraction of Goss grains is larger, and these grains had similar distributions in both the surface and middle layers.