Abstract: The microstructure evolution of copper⁃containing oriented silicon steel under different secondary cold rolling reduction rates was studied using electron backscatter technology (EBSD), and the loss characteristics were analyzed based on a loss separation model. The results showed that the decarburization annealed sample completely finished recrystallization, with an average grain size of about 10 μm; when the sample rolled to the thickness of the finished product, as the cold rolling reduction rate increases, the width of the deformation zone gradually decreases, and the orientation density of the {111}<112>fiber texture first increases and then decreases; when the cold rolling reduction rate is 62.3 %, the density of {111}<112> beneficial texture orientation reaches 7.1. In addition, the sample showed a lower content of the ∑3 unbeneficial grain boundary and a higher content of the ∑9 and ∑13b beneficial grain boundaries. The hysteresis loss of finished sample is low, resulting in an excellent magnetic property (P1.7/50=0.890 W/kg, B800=1.884 T).

Key words: copper?containing oriented silicon steel, cold rolling reduction rate, microstructure evolution, loss characteristics, hysteresis loss