STEEL Russian patent published in 2011 - IPC C22C38/38 C22C38/34 C22C38/32 

FIELD: metallurgy.

SUBSTANCE: steel contains carbon, manganese, silicon, aluminium, niobium, chromium, nitrogen, iron and impurities at following ratio of components, wt %: carbon 0.36 - 0.44, manganese 1.10 - 1.60, silicon 0.90 - 1.50, aluminium 0.005 - 0.025, niobium 0.010 - 0.030, chromium 0.80 - 1.20, nitrogen 0.008 - 0.020, iron and impurities - the rest. As impurities steel contains sulphur not more, than 0.030 %, phosphorus not more, than 0.030 % and copper not more, than 0.40 %.

EFFECT: reduced cleavability of balls at quenching in water, increased operational resistance due to increased hardenability and raised hardness on surface and through cross section.

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