STEEL SPS-430 Russian patent published in 2011 - IPC C22C38/50 

FIELD: metallurgy.

SUBSTANCE: steel contains carbon, silicon, manganese, chromium, nickel, molybdenum, calcium, titanium, aluminium, niobium, nitrogen and iron at following ratio of components, wt %: carbon 0.38 - 0.45, silicon1.30 - 1.60, manganese 0.50 - 0.80, chromium 1.00 - 1.40, nickel 1.10 - 1.60, molybdenum > 0.50 - 0.60, calcium 0.003 - 0.008, titanium 0.02 -0.05, aluminium 0.05 - 0.10, niobium 0.03 - 0.05, nitrogen 0.03 - 0.05, iron - the rest.

EFFECT: reduced degree of decarbonisation of blanks and parts of steel at all high temperature stages facilitating usage of blanks of less thickness at maintaining required level of service properties at manufacture of parts.

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