Austenitic heat resistant alloy with excellent liquid resistance of cracking resistance in the HAZ

摘要

PROBLEM TO BE SOLVED: To provide an austenitic heat resistant alloy which contains a lot of amount of Co and is excellent in weldability, among austenitic heat resistant alloys excellent in creep strength.;SOLUTION: The austenitic heat resistant alloy has a chemical composition containing C:0.03-0.15%, Si≤1%, Mn≤2%, Ni:40-80%, Cr:15-40% Mo:4-15%, Co:15-25%, Ti:≤3%, Al:≤2%, B:0.0005-0.01%, N:≤0.03%, O:≤0.03%, and the remainder of Fe and impurities, wherein P and S in the impurities are P:≤0.03%, S:≤0.03%, respectively. In the alloy, an average crystal particle size d (μm) satisfies [d≤-3300×(10×B+2×P+S)+250]. The austenitic heat resistant alloy may contain one or more of Ca:≤0.02%, Mg:≤0.02% and REM:≤0.08% in place of the portion of Fe.;COPYRIGHT: (C)2013,JPO&INPIT