Manufacturing method of high-grade non-oriented electrical steel sheet having small magnetic anisotropy

摘要

An object of the present invention is to provide a method for manufacturing a high-strength non-oriented electrical steel sheet having a high magnetic anisotropy by increasing the Al content of a silicon steel slab and controlling the rate of temperature rise during final cold rolling and final annealing.;The present invention relates to a method for producing a high-grade non-oriented electrical steel sheet, which comprises, by weight percent, 0.040% or less of C, 2.0 to 4.0% of Si, 0.5 to 2.0% of Al, 0.1 to 2.0% of Mn, O: 0.010% or less, and the balance of Fe and inevitably contained impurities is hot-rolled by a usual method and annealed to a hot rolled steel sheet, and then subjected to cold rolling twice or more, including intermediate annealing, And a final cold rolling rate of 60% or more at a temperature raising rate of 30 to 80C / sec to produce a high non-oriented electrical steel sheet having a small magnetic anisotropy.