The effect of grain size before cold rolling on the magnetic properties of thin-gauge non-oriented electrical steel

Thin-gauge non-oriented electrical steel was processed by one-stage cold rolling using different normalizing time, and the through-process texture evolution was studied. Strong {411}148 recrystallization textures were obtained in sheets subjected to longer normalization time. After cold rolling reduction, the initial {411}148 texture transformed to {114}110 and {311}136 textures. As the rolling reduction increased, the {311}136 texture transformed into a {112}110 texture, but not a {111}112 texture. In normalized sheets with large grains, more shear bands formed during cold rolling, which provided more nucleation sites for {100}013 oriented grains. The nucleation sites of {100}013 grains existed at {112}110 and {100}011 deformed grain boundaries and in the {112}110 and {111}112 orientation shear bands. Strong {100}013 textures formed due to the high mobility and large grain size. As the normalizing time increased, the magnetic properties were greatly improved in the final annealed sheets. The superior magnetic induction was due to the strong {100}013 and {210}001 textures and the weak {111}112 texture. A larger grain size and weaker gamma texture reduced the hysteresis loss, which caused low core losses in the final annealed sheets.