METHOD OF PRODUCTION OF STEEL HARD-DRAWN BAND Russian patent published in 2009 - IPC C21D9/52 C21D8/02 

FIELD: metallurgy.

SUBSTANCE: hot rolled flat bar of 2.0-2.8 mm thickness containing, wt %: 0.08-0.15 of carbon, 0.05-0.10 of silicon and 0.4-0.7 of manganese is subject to preliminary annealing in bell-type furnaces with conditioning during 4 h at temperature t₁=500°C and with conditioning during 10 h at t₂=560°C with total time of heating 20 h, further cold rolling is carried out for finish thickness h=0.5-1.0 mm accepting value of total reduction %, where: 212, 2.3 are empiric parametres obtained experimentally at setting nominal thickness in a finish stand of a continuous mill; upon this metal is subject to finish annealing with heating to 400°C and holding at this temperature during 10 h; successively to termination of heating time temperature is lowered up to 380°C; annealed band is skin-rolled with reduction 0.2-0.7%.

EFFECT: reaching required mechanical properties and quality of band surface.

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