PRODUCTION OF GRAIN-ORIENTED ELECTRICAL STEEL SHEET HAVING ARBITRARY MAGNETIC FLUX DENSITY WITH SMALL IRON LOSS

摘要

PURPOSE:To produce a grain-oriented electrical steel sheet having arbitrary magnetic flux density and small iron loss by carrying out cold rolling at a controlled draft and heating during finish annealing in a controlled atmosphere in accordance with desired magnetic flux density. CONSTITUTION:The grain-oriented electrical steel sheet is produced using the steel having a composition consisting of, by weight, 0.02-0.1% C, 2-4% Si, 0.03-0.2% Mn, 0.005-0.05% S, 0.01-0.05% Al, 0.0004-0.01% N, 0.01-0.05% one or more among Cu, Sn, Cr, Mo, Ni and Sb, and the balance Fe. At this time, final rolling is carried out at the draft (Red%) in the range of + or -5% of the draft calculated by B10(T)=logRed% in accordance with the desired magnetic flux density B10, and heating to 1,000 deg.C or below during the finish annealing is carried out in the atmosphere under the partial pressure PN2 of nitrogen in the range of + or -15% of a value calculated by the equation.