FIELD: metallurgy.
SUBSTANCE: invention relates to metallurgy, namely to a method of producing a sheet of electrical steel with an oriented grain structure, which is used as material for iron cores of transformers. Steel billet is hot-rolled with the following chemical composition, wt.%: from 0.030 to 0.100 % of C; from 0.80 to 7.00 % of Si; from 0.01 to 1.00 % of Mn; from 0 to 0.060 % in total of S and Se; from 0.010 to 0.065 % of acid-soluble Al; from 0.004 to 0.012 % of N; from 0 to 0.30 % of Cr; from 0 to 0.40 % of Cu; from 0 to 0.50 % of P; from 0 to 0.30 % of Sn; from 0 to 0.30 % of Sb; from 0 to 1.00 % of Ni; from 0 to 0.008 % of B; from 0 to 0.15 % of V; from 0 to 0.20 % of Nb; from 0 to 0.10 % of Mo; from 0 to 0.015 % of Ti; from 0 to 0.010 % of Bi, the rest is iron and impurities, with production of hot-rolled steel sheet, which is subjected to cold rolling with production of cold-rolled steel sheet. Decarbonization annealing is performed at temperature of 750–900 °C for 10–600 s and at a value of PH2O/PH2, which is an oxidation degree of atmosphere of 0.18–0.80. Annealing separator containing Al2O3 and MgO is applied, wherein the MgO/(MgO+Al2O3) value is 5–50 %, and the amount of hydrated water in the annealing separator is 1.5 wt.% or less. Finishing annealing of the sheet is carried out at 1,100–1,200 °C for 10 hours or more in a mixed gas atmosphere containing 50 vol.% or more of hydrogen. Excess annealing separator is removed by washing with water using a solution with an inhibitor, followed by etching, smoothing the surface and forming an insulating coating.
EFFECT: sheet has high magnetic characteristics and coating adhesion.
5 cl, 1 dwg, 13 tbl
