HEAT-RESISTANT ALLOY BASED ON NICKEL FOR MANUFACTURE OF BLADES OF GAS-TURBINE UNITS AND METHOD OF ITS HEAT TREATMENT

摘要

FIELD: metallurgy.;SUBSTANCE: invention relates to corrosion-resistant heat-resistant alloys based on nickel and can be used for manufacture of parts of a hot path of gas-turbine units operating in corrosive media. Heat-resistant alloy based on nickel contains the following, wt %: carbon 0.05-0.09; chrome 15.4-15.8; cobalt 10.0-10.4; tungsten 5.0-5.3; molybdenum 1.6-1.8; titanium 4.3-4.5; aluminium 3.0-3.2; boron 0.06-0.09; zirconium 0.015; hafnium 0.2-0.3; silicone 0.1; iron 0.1; copper 0.05; sulphur 0.005; nitrogen 20 ppm; oxygen 15 ppm, cerium 0.015; niobium 0.1-0.2; yttrium 0.03; manganese 0.1; phosphorus 0.005 and nickel is the rest. A manufacturing method of blades of gas-turbine units from heat-resistant alloy based on nickel is characterised by the fact that heat treatment is performed by homogenising annealing and ageing. Homogenising annealing is performed in inert atmosphere at heating rate of 5-10°C/min to the temperature of 1060±10°C, with exposure during 3-4 hours and cooling to the rate of 30-50°C/min to the temperature of 600-700°C and further to room temperature. Ageing is performed at the temperature of 850±10°C during 16 hours with further cooling in the air to room temperature.;EFFECT: increasing strength, ductility and corrosive resistance of an alloy with an equiaxial structure in combination with high structural stability for operating life and reduced level of gas shrinkage porosity.;2 cl, 2 tbl