METHOD OF PRODUCTION OF HIGH STRONG MARTENSITE AGEING STEEL

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FIELD : metallurgy.SUBSTANCE : invention relates to the production of high-strength maraging steels microalloyed with rare earth metals (REM), and can be used for manufacturing high-loaded parts of large cross-section, force parts operating from -70 to 400°C under high load conditions, for example, gas turbine engine shafts, parts of chassis, wing and other parts used in aircraft engineering and in mechanical engineering. Method includes loading charge containing iron, nickel, molybdenum, cobalt without wastes into vacuum induction furnace, its melting and deoxidation of rare-earth metals, introduction of titanium, forced melting followed by introduction of magnesium and calcium, melt casting, production of ingot and its further remelting in vacuum arc furnace. Nickel oxide is introduced into vacuum induction furnace after charge melt at rate of 0.45-0.55% of melt weight with holding for 15-30 Min at t=1600-1650°C, after that yttrium, dysprosium, neodymium, cerium, lanthanum in amount of 0.01-0.05% of each element are introduced as rare-earth metals in order to increase degree of their deoxidising capacity.EFFECT : invention makes it possible to reduce content of harmful impurities of carbon, nitrogen and sulphur, increase strength, plasticity and impact viscosity indexes, prevent formation of carbide and carbonitride grids at slow cooling from high temperatures after deformation.2 cl, 1 tbl