REFRACTORY ALLOY Russian patent published in 2017 - IPC C22C30/00 C22C19/05 

FIELD: metallurgy.

SUBSTANCE: refractory alloy is used for the manufacture of reformer tubes of coils, ethylene gas processing plants and other gas and oil processing installations, with operating modes at temperature of 650÷1000°C and pressures up to 10 atmospheres. Heat-resistant alloy contains, by wt %: carbon 0.35÷0.45; chrome 24.0÷27.0; nickel 18.0÷21.0; silicon 1.9÷2.5; manganese 1.0÷1.5; 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; sulfur ≤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-the rest, with the conditions must be satisfied simultaneously (Cr_E/Ni_E)0.735, where Cr_E is the equivalent of chromium; Ni_E is the equivalent of nickel; Cr_ECr+2xAl+3x Ti+V+Mo+l,6×Si+0,6×Nb; Ni_E=Ni+32x C+0.6x Mn+22x N+Cu.

EFFECT: increased structural alloy stability during aging, lowered alloy propensity to hot cracking at welding.

2 cl