HIGH STRENGTH CORROSION RESISTANT NITROGEN CONTAINING MARTENSITIC-AUSTENITIC-FERRITIC STEEL Russian patent published in 2023 - IPC C22C38/58 C22C38/46 

FIELD: steel metallurgy.

SUBSTANCE: alloyed corrosion-resistant high-strength martensitic-austenitic-ferritic steels used for the manufacture of highly loaded parts in mechanical engineering. Steel contains components in the following ratio, wt.%: carbon 0.02-0.05, nitrogen 0.11-0.20, chromium 17.5-20.0, manganese 1.0-2.0, nickel 2, 0-3.0, vanadium 0.07-0.13, silicon 0.2-0.4, cerium 0.005-0.03, lanthanum 0.005-0.03, barium 0.005-0.02, iron and other impurities. The content of components in steel satisfies the following conditions: Ni_eqv=%Ni+0.1%Mn-0.01%Mn²+30%C+18%N=4.67÷8.36 and Cr_eqv=%Cr+0.48%Si+2.3%V=17.76÷20.49.

EFFECT: increase in ductility and impact strength is ensured while maintaining high strength, which ensures increased operational reliability and an increase in the service life of structures made from this steel during their operation.

4 cl, 2 tbl