PROCEDURE FOR PRODUCTION OF SHEETS OUT OF COLD RESISTANT STEEL Russian patent published in 2010 - IPC C21D8/02 C21D9/46 

FIELD: metallurgy.

SUBSTANCE: work-piece is heated to temperature above AC₃. Further, it is deformed in 3 stages. Also during the preliminary stage the work-piece is deformed at the first three passes at temperature 950÷1050°C with reducing 6-10 % per pass and summary reducing not less, than 25 %. Then the work-piece is sub-cooled and is subject to intermediate deforming at temperature Ar₃+30°C with reduction not less, than 15 % per pass at summary deformation not less, than 55 %. Finish deformation is carried out at Ar₃ - 20°C with reduction as high as 8-10 % per pass, intervals between passes as high, as 5 sec and at summary reduction not less, than 40 %. The sheet is cooled at rate as high, as 30°C/min to temperature 400°C, and further - in air.

EFFECT: increased cold resistance of sheets out of low carbon ferrite-pearlite steel.

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