METHOD OF PRODUCING ANISOTROPIC ELECTRICAL STEEL Russian patent published in 1997 - IPC

FIELD: ferrous metallurgy. SUBSTANCE: method includes smelting, casting, and hot rolling of steel, one- or two-step cold rolling with decarbonization annealing between two rolling operations or after them, and, finally, high-temperature annealing in hydrogen or nitrogen-hydrogen mixtures. Method is distinguished by that, during high-temperature annealing, atmosphere moisture is varied from dew point at 30 to 0 C at metal temperature up to 600 C; respectively, from +5 to -10 at metal temperature 1150-1250 C; and from -25 to -50 C at maximum metal temperature. Moisture variation is provided by periodically and/or aperiodically varying oxidation potential of atmosphere specified by ratio achieved by way of changing hydrogen concentration in the range 20 to 100% in conformity with sawtooth functional relationship selected by program in dependence on temperature of annealed metal. EFFECT: improved magnetic properties of steel and quality of ground insulation coating. 1 dwg, 2 tbl