Method for rolling hot rolled steel strip for grain-oriented electrical steel and method for producing grain-oriented electrical steel sheet

摘要

PPROBLEM TO BE SOLVED: To provide a method of rolling a hot rolled steel strip for grain-oriented silicon steel and a method of producing a grain-oriented silicon steel sheet where edge cracks can be prevented effectively. PSOLUTION: In the method of producing a hot rolled steel strip for grain-oriented silicon steel where a slab for grain-oriented silicon steel as a starting stock is subjected to slab heating at 1,250 to 1,450C, and is thereafter subjected to rough rolling and finish rolling at a rolling starting temperature of 950 to 1,150C, slab heating conditions to the starting stock are controlled in such a manner that the ratio of the content of C (Cc) in the central layer of the slab to the content of C (Cs) to 5 mm of the surface layer on the side in the width direction of the slab subjected to the rough rolling, (Cs/Cc) reaches 0.40 to 0.86, further, after the rough rolling, till the finish rolling, sheet bar width rolling reduction is performed at a rolling draft of 5 to 60 mm by an edger mill, and also, the side temperature of the sheet bar before the finish rolling is controlled to the range of 1,150 to 1,250C. PCOPYRIGHT: (C)2006,JPO&NCIPI