HIGH-TEMPERATURE ALLOY Russian patent published in 2016 - IPC C22C30/00 C22C19/05 

FIELD: metallurgy.

SUBSTANCE: invention can be used for producing reaction tubes for hydrogen production plants, methanol, ammonia, etc, oil and gas processing plants, with operating modes at a temperature from plus 900 °C to plus 1160 °C and pressure of up to 20 atmospheres. Heat resistant alloy contains following component ratio, wt%: carbon 0.41÷0.47; chromium 26.5÷29.5; nickel 47.5÷50.5; tungsten 4.50÷5.50; silicon 0.9995÷1.49; manganese 0.5005÷1.51; vanadium 0.0005÷0.20; titanium 0.0005÷0.10, aluminium - 0.0005÷0.10; yttrium > 0÷0.001; oxygen > 0.0005÷0.028; hydrogen > 0.0005÷0.0025; nitrogen > 0.0005÷0.095; sulphur ≤ 0.03; phosphorus ≤ 0.03; lead ≤ 0.009; tin ≤ 0.009; arsenic ≤ 0.009; zinc ≤ 0.009; antimony ≤ 0.009; molybdenum ≤ 0.5; copper ≤ 0.2; iron - balance. For content of sulphur and phosphorus following condition is satisfied (S + P) ≤ 0.025, and for ratio of chromium and nickel equivalents, following condition is satisfied, wt%: (Cr_E/Ni_E) ≥ 0.561, where Cr_E - equivalent of chromium; Ni_E - nickel equivalent; Cr_E=Cr+2×Al+3×Ti+V+Mo+1.6×Si+W; Ni_E=Ni+32C+0.6×Mn+22×N+Cu.

EFFECT: increased structural stability of alloy in process of ageing, as well as reduced tendency to formation of hot cracks during welding.

3 cl