SUPERHIGH-STRENGTH, AIR-HARDENING, MULTIPHASE STEEL, HAVING EXCELLENT PROCESS CHARACTERISTICS, AND METHOD OF PRODUCING SAID STEEL

摘要

FIELD: metallurgy.;SUBSTANCE: invention relates to high-strength, air-hardening, multiphase steel used for production of cold-rolled or hot-rolled strips. Steel has the following composition, wt %: C from 0.075 to 0.145, Si from 0.400 to 0.500, Mn from 1.900 to 2.350, Cr from 0.200 to 0.500, Al from 0.005 to 0.060, N from 0.0020 to 0.0120, S 0.0030 or less, Nb from 0.005 up to 0.060, Ti from 0.005 to 0.060, B from 0.0005 to 0.0030, Mo from 0.200 to 0.300, Ca from 0.0005 to 0.0060, Cu 0.050 or less, Ni 0.050 or less, the rest—iron and unavoidable impurities.;EFFECT: steel has tensile strength in non-tempered state equal to 950 MPa, required moldability and weldability.;37 cl, 6 dwg, 2 ex