METHOD FOR PRODUCTION OF AN ELECTRICAL SHEET STEEL WITH A GRAIN-ORIENTED STRUCTURE Russian patent published in 2023 - IPC C21D8/12 C21D9/46 H01F1/147 C22C38/60 

FIELD: metallurgy.

SUBSTANCE: method for the production of an electrical sheet steel with a grain-oriented structure. A method for producing a grain-oriented electrical steel sheet includes a heating step, in which a steel slab containing, wt.%, Si 2.00-4.00, C 0.085 or less, Al 0.01-0.065, N 0.004-0.012, Mn 0.05-1.00, S 0.003-0.015, optionally one or more of B 0.0100 or less, Cr 0.30 or less, Cu 0.40 or less, P 0.50 or less, Sn 0.30 or less, Sb 0.30 or less, Ni 1.00 or less, Mo 0.1 or less, and Bi 0.01 or less with a balance of Fe and impurities, heated to a temperature of 1280°C or lower, a steel slab hot rolling step, a hot-rolled steel sheet annealing step, a hot-rolled sheet cold rolling step, a cold-rolled sheet decarburization annealing step, and a cold-rolled sheet finishing annealing step. The decarburization annealing step comprises the step of heating the cold-rolled sheet from the inlet temperature of the annealing furnace T0°C to 600°C or lower to holding temperature T2°C which is higher than the mentioned inlet temperature T0°C, and a holding step for maintaining the temperature of the cold-rolled sheet at the holding temperature T2°C. In the heating stage of the decarburization annealing stage, the heating rate HR1 of the cold-rolled sheet versus the inlet temperature T0°C to temperature T1°C, which is in the range of 700-900 °C and lower than holding temperature T2°C, set to 40°C/s or more, and the heating rate HR2 at which the temperature of the cold-rolled sheet changes from the temperature T1°C to the holding temperature T2°C, installed over 15°C/s and up to 30°C/s.

EFFECT: high characteristics of losses in the metal.

2 cl, 3 dwg, 3 tbl, 2 ex