HEAT-RESISTANT STEEL OF MARTENSITIC CLASS Russian patent published in 2018 - IPC C22C38/54 

FIELD: metallurgy.

SUBSTANCE: invention relates to the field of metallurgy, namely, to the heat-resistant chromium steels of the martensitic class used for the manufacture of turbine blades of power plants with an operating steam temperature of up to 650 °C. Steel contains the components in the following ratio, wt%: carbon 0.08–0.12; silicon is not more than 0.1; manganese is less than 0.05; chromium from 10.5 to 12.0; nickel is not more than 0.1; tungsten 1.5–2.5; molybdenum 0.4–1; cobalt 3–3.5; vanadium 0.18–0.25; niobium is not more than 0.07; nitrogen is not more than 0.003; boron 0.008–0.013; copper 0.6–0.8; sulfur is not more than 0.01; phosphorus is not more than 0.01; aluminum is not more than 0.01; titanium is to less than 0.01; iron – balance. Ratio of the chromium content to the copper content is 13.1–20.0, the total content of nickel and manganese is not more than 0.15 % by weight at a nickel: manganese ratio of 2:1.

EFFECT: indicators of long-term strength increase.

1 cl, 3 tbl