COLD-ROLLED STEEL FOR STAMPING COMPLEX-SHAPED DETAILS Russian patent published in 2002 - IPC

FIELD: ferrous metallurgy, particularly, chemical composition of low-carbon cold-rolled steels designed for production of complex-shaped articles by method of sheet stamping, mostly, automobiles details including protecting coverings. SUBSTANCE: steel contains components at the following ratio, mas. %: carbon, 0.002-0.015; silicon, 0.005-0.020; manganese, 0.05-0.2; sulfur, 0.005-0.015; phosphorus, 0.005-0.015; aluminum, 0.015-0.06; chromium, 0.005-0.04; nickel, 0.004-0.03; copper, 0.006-0.05; nitrogen, 0.001-0.006; titanium, 0.02-0.15; calcium, 0.0003-0.001; iron, the balance. Ratio of sulfur, calcium, nitrogen, carbon and titanium contents in steel is: 1.5 / S - 0.8Ca / + 3,43 N + 6C <Ti <1,5 / S - 0,8Ca / + 3.43N+10C. EFFECT: increased coefficient value of standard plastic anisotropy and index of strengthening at absence of steel age hardening after recrystallized annealing. 1 tbl