STEEL Russian patent published in 2011 - IPC C22C38/40 

FIELD: metallurgy.

SUBSTANCE: steel contains carbon, silicon, manganese, aluminium, nitrogen, chromium, nickel, calcium, iron and impurities at following ratio of components, wt %: carbon 0.65 - 0.80, manganese 0.70 - 0.90, silicon 0.20 - 0.40, aluminium 0.005 - 0.020, nitrogen from more, than 0.01 to 0.025, chromium 0.30 - 0.60, nickel 0.01 - 0.30, calcium 0.0005 - 0.0040, iron and impurities - the rest. As impurities steel contains sulphur - not over 0.030 %, phosphorus not over 0.030 % and copper - not over 0.30 %.

EFFECT: raised wear resistance and hardness on surface and in cross section of balls.

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