DIE STEEL Russian patent published in 2009 - IPC C22C38/58 

FIELD: metallurgy.

SUBSTANCE: steel contains carbon, silicon, manganese, chrome, vanadium, zirconium, nitrogen, boron, calcium, tantalum, nickel, tungsten, aluminium and iron at following relation of components, wt %: carbon 0.4-0.6, silicon 0.8-1.2, manganese 14.5-15.5, chrome 7.5-8.5, vanadium 3.6-4.0, zirconium 0.08-0.12, nitrogen 0.02-0.03, boron 0.1-0.13, calcium 0.007-0.009, tantalum 1.5-2.0, nickel 3.0-3.4, tungsten 1.1-1.3, aluminium 0.2-0.26, iron - the rest.

EFFECT: steel hardening.

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