Cold Rolled Non Oriented Silicon Steel Sheet

GNEE Steel Oriented Silicon Steel

Cold rolled non oriented silicon steel sheets are hot-rolled into coils with a thickness of approximately 2.3mm from damaged or continuously cast steel. When manufacturing low silicon products, the tropical coil is pickled and then cold rolled to a thickness of 0.5mm in one go. When manufacturing high silicon products, the hot rolled strip is cold rolled to 0.55 or 0.37mm thick after pickling (or normalized at 800-850C before pickling), and then 850 annealed in a hydrogen nitrogen mixed atmosphere continuous furnace, and then cold rolled to 0.50 or 0.35mm thick through a small reduction rate of 6-10%. Cold rolling with a small reduction rate can make the grains grow up during annealing, and reduce the iron loss. Both cold rolled sheets are finally annealed at 850C in a 20% hydrogen nitrogen mixed atmosphere continuous furnace, and then coated with phosphate plus Chromate and dichromate insulation film. Grain oriented silicon steel generally contains 3% Si3%, which requires a low content of oxide inclusions in the steel and must contain C0.03-0.05% and inhibitors (second phase dispersed particles or grain boundary segregation elements). The function of inhibitors is to prevent the growth of primary recrystallization grains and promote the development of secondary recrystallization, thereby achieving high (110) [001] orientation. The inhibitor itself is harmful to magnetism, so after completing the inhibitory effect, it must undergo high-temperature purification annealing. When using a second phase inhibitor, the heating temperature of the plate must be raised to allow the original coarse second phase particles to dissolve, and then precipitate as small particles during hot rolling or normalizing to enhance the inhibitory effect. The thickness of the cold-rolled finished product is 0.28, 0.30, or 0.35mm, and the process points are shown in Table 3. Cold rolled oriented thin silicon steel strip is made from 0.30 or 0.35mm thick oriented silicon steel strip, which is then pickled, cold rolled, and annealed.