OXIDATION-RESISTANT HEAT-RESISTANT ALLOY AND METHOD FOR ITS PRODUCTION Russian patent published in 2021 - IPC C22C1/02 C22C19/05 C22C30/00 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy, namely, an oxidation-resistant heat-resistant alloy and a method for its production. The oxidation-resistant heat-resistant alloy contains, wt. %: 2.5-6 Al, 24-30 Cr, 0.3-0.55 C, 30-50 Ni, 2-8 W, 0.01-0.2 Zr, 0.01-0.4 Hf, 0.01-0.2 Y, one of the elements: 0.01-0.2 Ti or 0.01-0.2 V, the rest is Fe and unavoidable impurities, including N <0.05, O <0.003, S <0.003 and Si <0.5. The method for producing an oxidation-resistant heat-resistant alloy includes the following steps: stage 1: placing inactive nickel, chromium, iron and tungsten elements in the crucible and melting them, adding a part of graphite for preliminary deoxidation to obtain a molten alloy; stage 2: heating the molten alloy, adding the remaining part of graphite when the alloy temperature reaches at least 1640°C for refining; stage 3: adding a mixture of La and Ce in an amount of 0.05-0.25, wt. %; stage 4: addition of protective slag containing CaO to the surface of the alloy melt in an amount of 3-5% of the amount of molten alloy; and stage 5: introduction of inert gas into the channel connecting the crucible to the intermediate ladle, placement of active elements of aluminum, hafnium, titanium, zirconium and yttrium in the channel, heating the alloy obtained in stages 1-4 to a temperature of 1650-1750°C, pouring it onto the active elements placed in the channel and releasing the resulting alloy through the channel into the intermediate ladle for casting; stage 6: casting of molten alloy at a speed of 60-100 kg/min.

EFFECT: resulting alloy is characterized by high mechanical properties and resistance to oxidation at temperatures up to 1100°C.

6 cl, 8 dwg, 6 tbl