| 摘要 |
PROBLEM TO BE SOLVED: To provide an austenitic heat resistant alloy having excellent creep strength.SOLUTION: The austenitic heat resistant alloy has a chemical composition which contains by mass%, C:less than 0.020%, Si:2% or less, Mn:2% or less, P:0.04% or less, S:0.01% or less, Cr:15 to 24%, Ni:25 to 34%, Nb:2.3 to 5.5%, Ta:0.3 to 5%, Al:0.3% or less, N:0.05% or less or the like and the balance Fe with impurities, and in which f1 defined by the following formula (1) is 2.8 to 6.5 and f2 defined by the following formula (2) is 3.3 to 7.5. f1:Nb+0.5×Ta... (1). f2:(Nb+0.5Ta+4.2)×Cr/Ni... (2), where for each element symbol in the formula (1) and the formula (2), content of corresponding element represented by mass% is substituted.SELECTED DRAWING: Figure 1 |
