ARMOURED STEEL Russian patent published in 2008 - IPC C22C38/48 

FIELD: metallurgy.

SUBSTANCE: steel contains carbon, silicon, manganese, chrome, nickel, molybdenum, vanadium, aluminium, nitrogen, copper, niobium, sulphur, phosphor and iron, at following components ratio, wt %: carbon 0.29-0.38, silicon 0.15-0.37, manganese 0.30-0.60, chrome 1.20-2.00, nickel 1.20-2.20, molybdenum 0.72-0.90, vanadium 0.06-0.20, aluminium 0.01-0.05, nitrogen 0.005-0.020, copper is not more than 0.50, niobium is not more than 0.05, sulphur is not more than 0.012, phosphor is not more than 0.015, iron - the rest.

EFFECT: increasing of viscosity reserve, strengthening and plastic performance of steel, high shellproof endurance and armor survival.

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