METHOD FOR PRODUCING COLD-ROLLED CONTINUOUSLY ANNEALED FLAT STOCK OF IF-STEEL Russian patent published in 2021 - IPC C21D1/26 C21D8/04 

FIELD: metallurgy.

SUBSTANCE: invention relates to the field of metallurgy, namely to methods for producing cold-rolled stock of ultra-low-carbon IF-steels, usable in the automobile industry. The method for producing a cold-rolled strip of IF-steel includes smelting the steel, casting, hot rolling to produce strips, etching, winding the strips into rolls, cold rolling the strips, performing recrystallisation annealing in a continuous annealing aggregate, and pinch rolling. Steel is smelted, containing, % wt.: C 0.002 to 0.005, Si 0.01 to 0.020, Mn 0.06 to 0.15, Al 0.02 to 0.05, Ti 0.04 to 0.07, Fe and inevitable impurities the rest, hot rolling is finished at a temperature of 900 to 920°C, and recrystallisation annealing of the cold-rolled strip is performed at a temperature of 850 to 870°C, wherein the rate of movement of the strip in the continuous annealing aggregate is no more than 90 m/min.

EFFECT: increased ductility of the cold-rolled stock, stability of the strength characteristics thereof, as well as corrosion resistance, is achieved while maintaining high values of stampability.

1 cl, 3 tbl, 2 ex