PURPOSE: To produce a high tension film with superior adhesion and to attain ultralow core loss by providing a mirror finished grain oriented silicon steel sheet excellent in film adhesion and having high magnetic flux density.
CONSTITUTION: A hot rolled strip of a silicon steel, having a composition containing 2-4.8% Si, 0.008-0.06% acid soluble Al, ≤0.01% N, 0.0005-0.0060% B, and 0.0050-0.120% C, is cold-rolled once or cold-rolled two or more times while process-annealed between the cold rolling stages to the final sheet thickness. After primary recrystallization annealing, an oxide layer forming at the time of primary recrystallization annealing is removed, if necessary, from the surface of the steel sheet. After the application of a separation agent at annealing, finish annealing is done and then a tension film is applied. By this method, the mirror finished grain oriented silicon steel sheet with high magnetic flux density can be obtained. Because high tension film can be applied to this steel sheet with superior adhesion and ultralow core loss can be attained and also this steel sheet can contribute to energy loss reduction, a great social contribution can be made.
USHIGAMI YOSHIYUKI
TAKAHASHI NOBUYUKI
SUGA YOZO
MASUI HIROAKI
KUROKI KATSURO
YAMAZAKI SHUICHI
FUJII HIROYASU
| JPH0533052A | 1993-02-09 |
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