STEEL Russian patent published in 2009 - IPC C22C38/60 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy field, particularly to compound of steel for manufacturing of sheet products. Steel contains carbon, silicon, manganese, aluminium, titanium, calcium, boron, niobium, zirconium, copper, selenium and iron at following components' ratio, wt %: carbon 0.05 - 0.15, silicon 0.05 - 0.15, manganese 0.2 - 0.3, aluminium 0.05 - 0.15, titanium 0.05 - 0.15, calcium 0.003 - 0.005, boron 0.03 - 0.05, niobium 0.6 - 0.9, zirconium 0.1 - 0.15, copper 3.4 - 3.8, selenium 0.001 - 0.003, iron is the rest.

EFFECT: increasing of steel durability.

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