MANUFACTURE OF GRAIN-ORIENTED SILICON STEEL SHEET

PURPOSE:To manufacture a grain-oriented silicon steel sheet having superior magnetic characteristics by hot rolling a silicon steel slab contg. a specified amt. of Si in a specified temp. range under specified rolling conditions. CONSTITUTION:A silicon steel slab contg. 2.0-4.5wt.% Si is hot rolled in the temp. range of 1,050-1,150 deg.C temp. of the slab under rolling conditions satisfying relation represented by an inequality r>=68.1+43.3(hi/D)-51.0mu (where r is draft (%), hi is the thickness (mm) of the slab at the inlet of a rolling mill, D is the diameter (mm) of rolling rolls and mum is the coefft. of friction between the rolling rolls and the slab). Effective shearing strain is produced in the slab by rolling under the conditions and the recrystallization of grains coarsened by heating is effectively facilitated, so a grain-oriented silicon steel sheet having superior magnetic characteristics is obtd.