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 700 to 950 C and pressure up to 45 atm. Alloy contains, wt.%: carbon, 0.08-0.14; chromium, 19.0-21.0; nickel, 31.0-34.0; niobium, 0.90-1.35; silicon, 0.0005-0.79; manganese, 0.5005-1.21; 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=(34.96984 to 39.406)% and %Cr+3*%Ti+%V%+Mo+1.6*%Si+0.6*%Nb =(19.5433 to 23.16786)%. EFFECT: increased average grain size and increased homogeneity of alloy structure. 3 cl