PRODUCTION METHOD OF GRAIN-ORIENTED MAGNETIC PLATE STEEL Russian patent published in 2014 - IPC C21D8/12 C22C38/60 H01F1/16 

FIELD: metallurgy.

SUBSTANCE: invention involves hot rolling of material from silicon steel containing the following, wt %: Si 0.8 to 7, Al diluted in acid 0.01 to 0.065, N 0.004 to 0.012, Mn 0.05 to 1 and B 0.0005 to 0.0080, C 0.085 or less, Ti 0.004 or less, at least one element chosen from the group consisting of S and Se, which are 0.003 to 0.015 wt %, Fe and inevitable impurities are the rest, annealing of a hot-rolled steel strip, single or multiple cold rolling, decarburising annealing for primary recrystallisation, application of an annealing separator containing MgO as its main component and final annealing for secondary recrystallisation; besides, between the beginning of decarburising annealing (stage S4) and occurrence of crystals of secondary recrystallisation at final decarburisation (stage S5) there performed is nitrate treatment (stage S6) for increase in content of N in a decarburised annealed steel strip, and at hot rolling (stage S1) material of silicon steel is exposed at the temperature of 1000 to 800°C during 300 seconds or longer, and then, finish rolling is performed.

EFFECT: providing high density of a magnetic flux in steel.

9 cl, 11 dwg, 16 tbl, 19 ex