PRODUCTION OF EXTRA THIN GRAIN-ORIENTED SILICON STEEL SHEET HAVING HIGH MAGNETIC FLUX DENSITY

PURPOSE:To produce an extra thin grain-oriented silicon steel sheet having high magnetic flux density at a low cost by forming a cast thin slab prepared by applying rapid solidification to a molten silicon steel containing specific amounts of Si to a specific sheet thickness of final product by means of cold rolling at a specific final cold draft. CONSTITUTION:A molten silicon steel containing 2.5-4.5% Si and other required components, such as inhibitor components, is subjected to continuous rapid solidification so as to be formed into a cast thin slab. After annealed at about 950-1200 deg.C for about 30sec-30min, the cast thin slab is cold-rolled once or is cold-rolled twice or more while process-annealed between the cold rolling stages so that final cold rolling draft is regulated to >=80%, preferably >= about 90%, until a final product sheet thickness of