FIELD: metallurgy.
SUBSTANCE: invention relates to the field of metallurgy, namely to the production of a sheet of electrical steel with a grain-oriented structure used as a material for iron cores of transformers. Hot rolling of a steel billet is carried out, having a chemical composition, wt.%: from 0.030 to 0.100 C, from 0.80 to 7.00 Si, from 0.01 to 1.00 Mn, from 0 to 0.060 in the sum of S and Se, 0.010 to 0.065 acid soluble Al, 0.004 to 0.012 N, 0 to 0.30 Cr, 0 to 0.40 Cu, 0 to 0.50 P, 0 to 0.30 Sn, 0 to 0, 30 Sb, 0 to 1.00 Ni, 0 to 0.008 V, 0 to 0.15 V, 0 to 0.20 Nb, 0 to 0.10 Mo, 0 to 0.015 Ti, 0 to 0.010 Bi, the rest is iron and impurities, to obtain a hot-rolled steel sheet. Cold rolling is carried out to obtain a cold-rolled steel sheet, which is subjected to decarburization annealing in an atmosphere with a PH2O/PH2oxidation state of 0.18-0.80 at a temperature of 750-900°C and a holding time of 10-600 s. An annealing separator comprising MgO and MCl, which is at least one of an alkali metal chloride, an alkaline earth metal chloride and Bi, is applied at an MCl/MgO value of 2-40%, and dried. Finish annealing is carried out at an oxidation state of 0.00010-0.2 in a hydrogen-containing atmosphere or at a dew point of 0°C in an atmosphere consisting of an inert gas without hydrogen. The excess annealing separator is removed from the surface of the finished annealed sheet, and an insulating coating is formed by applying a solution including mainly phosphate or colloidal silica, baking the solution at 350-600°C, and then subjecting it to heat treatment at 800-1000°C.
EFFECT: sheet has excellent magnetic performance and coating adhesion.
6 cl, 1 dwg, 10 tbl
