SECTION IRON, ROUND MADE OF LOW-CARBON HIGH-PLASTIC STEEL FOR COLD FORGING Russian patent published in 2008 - IPC C21D8/06 C22C38/14 C22C38/60 

FIELD: metallurgy.

SUBSTANCE: invention concerns the metallurgy field. Particularly it concerns manufacturing of section iron of diameter from 12 to 36 mm. Technica result is obtained by getting section iron from steel which consists in mass % of: C - 0.04-0.11, Mn - 0.25-0.60, Si - 0.01-0.055, Al - 0.03-0.05, S - 0.005-0.015, P - 0.005-0.020, N - 0.005-0.015, O₂ - 0.00-0.015, As - 0.0001-0.03, Sn - 0.0001-0.02, Pb - 0.0001-0.01, Zn - 0.0001-0.005, iron and inevitable admixtures are the rest, in ratio: As+Sn+Pb+5×Zn≤0.07. Section iron has following macrostructure - center porosity, spot inhomogeneity, liquating square - not more than 3 points for every kind, undershrinked sweat - not more than 3 points; liquating strip - not more than 1 point, nonmetallic by sulphides, oxides, silicates and nitrides of dimension not more than 3 points for every kind of inclusions, homogeneous length spheroidised structure, which consists of not less than 60% granular pearlite, effective grain size is - 5-10 points, value of cold yielding is not less than 1/3 of height and mechanical properties: σ_"в" - not more than 460 MPa, δ - not less than 28%, ψ - not less than 65%, solidity is not more than 160 HB.

EFFECT: obtaining of heightened specifications technological plasticity and viscosity of section iron for supplying of efficient conditions for cold forging of figurine fasteners.

3 cl, 2 ex