HEAT-RESISTANT STEEL OF THE MARTENSITIC CLASS Russian patent published in 2021 - IPC C22C38/54 

FIELD: metallurgy.

SUBSTANCE: invention relates to the field of metallurgy, namely to heat-resistant chromium steel of the martensitic class used for the manufacture of turbine blades of power plants with an operating steam temperature of up to 650°С. Steel contains components at the following ratio, wt. %: carbon 0.080–0.120, silicon no more than 0.120, manganese 0.010-0.100, chromium 9.000-10.500, nickel no more than 0.25, tungsten 1.900-2.500, molybdenum 0.600-0.700, vanadium 0.170-0.250, niobium 0.040-0.070, nitrogen no more than 0.003, boron 0.008-0.015, cobalt 2.500-3.500, rhenium 0.100-0.200, copper 0.750-1.000, sulfur not more than 0.006, phosphorus not more than 0.010, aluminum not more than 0.030, titanium not more than 0.010, iron the rest. The amount of tungsten and molybdenum is determined from the condition that the value of the molybdenum equivalent, expressed by the formula Mo_eq=Mo+0.5 W, lies in the range of 1.55-1.95.

EFFECT: increase in the indicators of long-term strength is provided.

1 cl, 2 dwg, 3 tbl