Abnormal Growth of Goss Grains in Grain-oriented Electrical Steels

With the help of electron back scattering diffraction techniques and field emission microscope, the misorientation and the precipitation environment of Goss grains in conventional grain-oriented steel were observed and investigated at the initial stage of secondary recrystallization. It reveals that the abnormal Goss grains have a high fraction of high angle boundaries ranging from 25 to 40 deg. The most important observation is that some of {110}<001> grains in matrix indicated higher particle density than their neighbor grains during final annealing at 875°C before secondary recrystallization, which could create a favorable environment for their abnormal grain growth. Based on misorientation and precipitation results, the abnormal growth mechanism of Goss grains was sketched.