HEAT-RESISTANT ALLOY Russian patent published in 2002 - IPC

FIELD: metallurgy. SUBSTANCE: invention relates to composites of heat-resistant low-carbon chrome-nickel alloys of austenite class. Invention proposes heat-resistant alloy comprising components taken in the following ratio, wt.-%: carbon, 0.10-0.25; silicon, 1.195-1.95; manganese, 0.050-1.55; chrome, 24.0-27.0; nickel, 38.0-41.0; molybdenum, 1.0-3.1; titanium, 0.20-0.60; boron, 0.0005-0.01; zirconium, 0.0005-0.05; tungsten, 0.2-0.8; vanadium, 0.0005-0.10; aluminum, 0.0005-0.10; iron, the balance. Content of sulfur, phosphorus, lead, tin, arsenic, zinc and copper in heat-resistant alloy does not exceed the following values, wt.-%: sulfur, 0.025; phosphorus, 0.025; lead, 0.01; tin, 0.01; arsenic, 0.01; zinc, 0.01; copper, 0.2. The following conditions must be maintained simultaneously: % Ni + 32 % C + 0.6% Mn + % Cu = 43.652-50.13%; % Cr + 3% Ti + % V + % Mo + 1.6% Si + % W = 27.7125-34.2785%. Invention can be used in making reaction tubes of petroleum-gas- -processing devices working at temperatures 700-1060 c under pressure below 46 atm. Invention provides increase of average grains size and enhancement of uniformity of alloy structure. EFFECT: enhanced heat resistance of alloy. 3 cl