| 摘要 |
PURPOSE:To produce a grain-oriented electrical steel sheet having a high magnetic flux density and small iron loss by subjecting a hot rolled steel sheet having a specific compsn. contg. Si, C, Sn, etc. to an adequate heat treatment and final cold rolling then applying tension coating thereon after decarburization and finish annealing. CONSTITUTION:A hot rolled steel sheet contg. 2.5-4.5% Si, 0.02-0.10% C, 0.04- 0.4% Sn, 0.015-0.040% sol Al, 0.0040-0.0100% N, 0.030-0.150% Mn, 0.015- 0.040% S, <=0.04% Se and <=0.4%>=1 kind among Sb, Cu, As and Bi is held for 10-600sec at 900-1,200 deg.C or <=100sec at 1,050-1,200 deg.C and is then held for 30- 500sec at 800-1,000 deg.C and is then cooled down to 100 deg.C in 3-50sec. The steel sheet is rolled at 81-93% draft in the final cold rolling, thereafter and the steel sheet is heated for 30sec at 150-300 deg.C at least twice and is made into 0.15-0.23mm. final thickness between rolling passes. The steel sheet is subjected to decarburization annealing and finish annealing in an atmosphere consisting of >=50% H2 and N2 and is then subjected to tension coating, by which the grain- oriented electrical steel sheet having W17/50<=0.90W/kg is obtd. |
