REFRACTORY ALLOY Russian patent published in 2000 - IPC

FIELD: metallurgy. SUBSTANCE: invention relates to refractory high-carbon austenite-type chromium-nickel alloys and can be used in manufacture of reaction tubes for oil-and-gas-processing plants operated at temperature 950 to 1200 C and pressure up to 10 atm. Alloy contains, wt.%: carbon, 0.40-0.50; chromium, 24.0-28.0; nickel, 34.0-36.0; niobium, 1.30-1.70; cerium, 0.08-0.12; silicon, 1.8995-2.39; manganese, 0.0005-0.51; vanadium, 0.0005-0.20; titanium, 0.0005-0.10; aluminum, 0.0005-0.10; iron, the balance. Weight percentages of following minerals do not exceed indicated values: sulfur, 0.03; phosphorus, 0.03; lead, 0.01; tin, 0.01; arsenic, 0.01; zinc, 0.01; molybdenum, 0.5; and copper, 0.2. Simultaneously, two following conditions are to be met: %Ni+32*%C+0.6*%Mn+%Cu= (47.94875 to 52.506)% and %Cr+3*%N+%Mo+1.6*%Si+0.6*%Nb= (27.8217 to 32.63954)%. EFFECT: increased average grain size and increased homogeneity of alloy structure. 3 cl