HEAT RESISTANT STEEL Russian patent published in 2011 - IPC C22C38/60 C22C38/54 

FIELD: metallurgy.

SUBSTANCE: invention refers to composition of heat resistant steel designed for fabrication of elements of heat power units operating at temperature to 650°C, particularly pipes of heating surface of superheaters and steam pipelines. Steel contains carbon, silicon, manganese, chromium, tungsten, molybdenum, vanadium, niobium, calcium, cerium, nitrogen, boron, cobalt, aluminium, nickel, phosphorus, sulphur, lead, tin, arsenic and iron at the following ratio of components, wt %: carbon from 0.08 to 0.12, silicon from 0.15 to 0.20, manganese from 0.4 to 0.6, chromium from 8.0 to 9.5, cobalt from 3.0 to 4.0, molybdenum from 0.4 to 0.6, tungsten from 1.8 to 3.0, vanadium from 0.15 to 0.30, niobium from 0.04 to 0.09, aluminium not over 0.015, nickel not over 0.2, calcium from 0.005 to 0.05, nitrogen from 0.03 to 0.07, cerium from 0.02 to 0.05, boron from 0.001 to 0.006, phosphorus not over 0.015, sulphur not over 0.010, lead not over 0.006, tin not over 0.006, arsenic not over 0.006, iron - the rest.

EFFECT: steel possesses high level of heat resistance, plasticity, impact strength, stability at long-term isothermal conditioning, and also processability and efficiency at production.

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