FIELD: metallurgy.
SUBSTANCE: there is melted steel containing wt %: from 0.045 to 0.065 of carbon, from 2.5 to 3.5 of silicon, from 0.05 to 0.40 of manganese, from 0.004 to 0.013 of nitrogen, less, than 0.012 of sulphur, from 0.010 to 0.040 of acid-soluble aluminium, less, than 0.005 of titanium, iron and unavoidable additives - the rest. Further, steel is continuously cast into slabs of 200-270 mm thickness. Slabs are placed into a heating furnace at temperature of slab surface not less, than 450°C, are heated prior to hot rolling to temperature 1100-1200°C, are hot rolled, annealed and conditioned from 1070 to 1200°C. The slabs are cooled at rate from 6 to 12°C/s to temperature from 900 to 980°C, conditioned and rapidly cooled from temperature 800-950°C at rate from 20 to 50°C/s with water of temperature from 35 to 65°C. In 120 hours after annealing there is carried out cold rolling of slabs in one or several stages. Cold rolled strip is continuously annealed at rate of heating from 16 to 60°C/s to temperature 750-800°C, and conditioned at temperature of de-carbonisation. Further, there is performed nitriding at temperature from 750 to 850°C in nitrogen-hydrogen atmosphere containing ammonia NH3.
EFFECT: improved magnetic properties of anisotropic electro-technical steel and low losses for re-magnetising; high magnetic induction.
9 cl, 2 tbl
