MANUFACTURING METHOD OF PLATE FROM GRAIN-ORIENTED ELECTRICAL STEEL Russian patent published in 2015 - IPC C21D8/12 C23C22/00 C22C38/02 

FIELD: metallurgy.

SUBSTANCE: method involves hot rolling of a steel slab containing the following, wt %: C 0.001-0.10, Si 1.0-5.0, Mn 0.01-1.0, at least one element from S and Se 0.01-0.05 in total, soluble Al 0.003-0.050, N 0.001-0.020, one-time or repeated cold rolling with intermediate annealing between them till final thickness, primary recrystallisation annealing, application of an annealing separator mainly consisting of MgO, and final annealing; with that, at primary recrystallisation annealing the speed S1 of temperature rise within 500-600°C is at least 100°C/s and speed S2 of temperature rise within 600-700°C is 30°C/s-0.6×S1°C/s. The annealing separator from MgO contains an element having an ionic radius of 0.6~1.3 E and force of gravity between an ion and oxygen of not more than 0.7 E-2, the total content of which W(mol %) is controlled so that S2 meets the following equation: 0.01S2-5.5≤Ln(W)≤0.01S2-4.3.

EFFECT: increasing magnetic properties and quality of a coating of a plate from grain-oriented electrical steel.

7 cl, 3 tbl, 2 ex