| 摘要 |
FIELD: metallurgy.SUBSTANCE: invention refers to metallurgy, and namely to surface-strengthened steel. Steel contains the following, wt %: 0.05-0.20 C, 0.01-0.1 Si, 0.3-0.6 Mn, 0,03 or less P (except for 0), 0.001-0.02 S, 1.2-2.0 Cr, 0.01-0.1 Al, 0.010-0.10 Ti, 0.010 or less N (except for 0), 0.0005-0.005 B, iron and inevitable impurities are the rest. Density of released phases based on Ti, which have a diameter of equivalent circle of less than 20 nm in surface-strengthened steel, is 10-100 particles/mcm, density of released phases based on Ti, which have a diameter of equivalent circle of 20 nm or more in surface-strengthened steel, is 1.5-10 particles/mcm, and Vickers hardness number is 130 HV or less.EFFECT: steel has high usability for cold forming and high characteristics preventing enlargement of crystalline grains after carbonisation.7 cl, 1 dwg, 4 tbl, 1 ex |
