HIGH-STRENGTH WELDED COLD-RESISTANT STEEL AND ARTICLE MADE THEREFROM Russian patent published in 2020 - IPC C22C38/60 C22C38/48 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy, namely to production of rolled sheet in thicknesses of up to 50 mm from high-strength welded cold-resistant steel for production of heavy-duty equipment, handling equipment and ice-resistant offshore platforms operated in low temperature conditions. Steel contains in wt. %: carbon 0.08–0.10, silicon 0.30–0.40, manganese 0.65–0.75, chrome 0.45–0.55, nickel 1.65–1.75, copper 0.50–0.60, molybdenum 0.30–0.35, niobium 0.02–0.04, zinc 0.0001–0.01, bismuth 0.0001–0.005, antimony 0.0001–0.005, calcium 0.0001–0.01, aluminium 0.02–0.05, nitrogen 0.001–0.008, sulphur no more than 0.005, phosphorus not more, than 0.012, rest are iron and unavoidable impurities. Value of carbon equivalent does not exceed 0.53 %. Products made from steel have a quasi-uniform in thickness fine-dispersed bainitic or bainitic-martensite structure without structurally free ferrite.

EFFECT: providing the required guaranteed level of mechanical properties.

2 cl, 3 tbl, 1 ex