AUSTENITIC HEAT-RESISTANT ALLOY

摘要

An austenitic heat resistant alloy consisting of, by mass percent, C: 0.15% or less, Si: 2% or less, Mn: 3% or less, Ni: 40 to 60%, Co: 0.03 to 25%, Cr: 15% or more and less than 28%, either one or both of Mo: 12% or less and W: less than 4%, the total content thereof being 0.1 to 12%, Nd: 0.001 to 0.1%, B: 0.0005 to 0.006%, N: 0.03% or less, O: 0.03% or less, at least one selected from Al: 3% or less, Ti: 3% or less, and Nb: 3% or less, the balance being Fe and impurities, and the contents of P and S in the impurities being P: 0.03% or less and S: 0.01% or less, wherein the alloy satisfies 1 ‰¤ 4xAl + 2xTi + Nb ‰¤ 12 and P + 0.2×Cr×B ‰¤ 0.035, is excellent in both of weld crack resistance and toughness of HAZ, and is further excellent in creep strength at high temperatures.