STEELS WITH HIGH TENSILE STRENGTH AND HIGH IMPACT VISCOSITY Russian patent published in 2022 - IPC C21D8/10 C21D9/08 C22C38/54 

FIELD: metallurgy.

SUBSTANCE: invention relates to the field of metallurgy, namely to alloyed steels for the manufacture of seamless pipes used in Arctic conditions and at low temperatures. Steel has the following chemical composition, wt.%: C: from 0.27 to 0.30, Si: from 0.20 to 0.35, Mn: from 0.80 to 0.90, Cr: from 1.30 to 1.45, Mo: from 0.65 to 0.75, Ni: from 0.15 to 0.25, Cu: 0.25 max, Al: from 0.015 to 0.035, Ti: from 0.024 to 0.038, N: 0.012 max, V: 0.05 max, B: from 0.001 to 0.0025, Nb: from 0.02 to 0.03, the rest is iron and unavoidable impurities. Steel has yield strength (Ys) of at least 862 MPa and ultimate tensile strength (UTS), wherein the ratio between yield strength (Ys) and ultimate tensile strength (UTS) is less than 0.93.

EFFECT: required and stable mechanical properties are provided, as well as high characteristics of impact viscosity at ultralow operating temperatures.

16 cl, 7 dwg, 20 tbl, 1 ex