To obtain an alloy exhibiting a reduced loss of oxidation and excellent oxidation resistance by allowing it to have a compsn. contg. specified ratios of C, Si, Mn, Ni, Cr, CuO, Ti, Al, and the balance Fe.
This heat resistant alloy is the one having a compsn. contg., by weight, 0.03 to 0.10% C, ≤3.0% Si, ≤1.5% Mn, 20 to 35% Ni, 12 to 25% Cr, 0.8 to 5.0% Cu, 0.1 to <0.5% Ti, 0.1 to <0.5% Al, and the balance Fe and excellent in oxidation resistance. Preferably, the alloy contains one or more kinds among the group of 0.1 to 0.5% Nb and Ta, ≤1.5% Mo and ≤3.0% W for increasing its high temp. strength, the group of 0.001 to 0.010% B and 0.001 to 0.1% Zr for increasing the grain boundaries and the group of 0.001 to 0.01% Ca and 0.001 to 0.01% Mg for reducing free S. Desirably, in the impurities, the content of P is controlled to ≤0.025% and that of S to ≤0.001%. It is suitable, e.g. for a member for a heating furnace in which heating at high temp. and cooling are repeated.
NODA TOSHIHARU
OKABE MICHIO
