COLD-RESISTANT HIGH-STRENGTH STEEL Russian patent published in 2021 - IPC C22C38/50 C22C38/48 

FIELD: metallurgy.

SUBSTANCE: invention relates to the field of metallurgy, namely to high-strength cold-resistant steels used in the production of pressure vessels used for storage and transportation of compressed gases in a wide range of temperatures, including those operated at low (down to -60°C) temperatures. Steel contains components in the following ratio, wt%: carbon - 0.22-0.28, silicon - 0.15-0.30, manganese - 0.30-0.60, chromium - 1.20-1.40, nickel - 2.85-3.50, copper - 0.40-0.70, molybdenum - 0.25-0.35, niobium - 0.02-0.05, zirconium and / or zirconium carbonitride - 0.005-0.10 in total, cerium - 0.001- 0.020, vanadium - 0.05-0.08, aluminum - 0.005-0.02, calcium - 0.005-0.01, if necessary, at least one element selected from the group: titanium - 0.005-0.035, gadolinium - 0.008-0.015, yttrium - 0.001- 0.02, nitrogen - 0.005-0.012 and barium - 0.005-0.025, the rest is iron and impurities. The total content of niobium, vanadium and titanium is 0.15 or less. The total content of low-melting impurities of lead, bismuth, tin, antimony and arsenic does not exceed 0.05 wt%, and the content of inevitable impurities of sulfur, phosphorus and oxygen does not exceed, wt%: sulfur ≤0.008, phosphorus ≤0.008 and oxygen ≤0.005.

EFFECT: steel possesses the required high level and stability of performance characteristics, including strength, impact toughness and ductility at temperatures from plus 60°C to minus 50°C.

1 cl, 1 tbl