HOT ROLLED STEEL AND STEEL COMPONENT Russian patent published in 2019 - IPC C22C38/60 C21D8/00 

FIELD: metallurgy.

SUBSTANCE: invention relates to the field of metallurgy, namely to hot rolled steel used for the manufacture of engine components and vehicle suspension system. Steel has the following chemical composition, wt.%: C: from 0.35 to 0.45; Si: from 0.6 to 1.0; Mn: from 0.60 to 0.90; P: from 0.010 to 0.035; S: from 0.06 to 0.10; Cr: 0.25 or less; V: from 0.20 to 0.40; Zr: from 0.0002 to 0.0050; N: from 0.0060 to 0.0150; Bi: from 0.0001 to 0.0050; Ti: from 0 to 0.050; Nb: from 0 to 0.030; Mg: from 0 to 0.0050. REM: from 0 to 0.0010; residue is iron and impurities. Metallographic structure is 90 % or more of the area formed by ferrite and perlite. Average numerical density of sulfides Mn, that have an equivalent circle diameter from 1 to 5 mcm, extended along the rolling direction and having an aspect ratio of, greater than 10 and equal to or less than 30, measured on a section parallel to the direction of rolling, is 50–200 pcs/mm².

EFFECT: steel has a high machinability by cutting, a small amount of plastic deformation near the surface of destruction and a small amount of fragments at destruction.

5 cl, 2 dwg, 5 tbl, 2 ex