| 摘要 |
PROBLEM TO BE SOLVED: To provide a high strength Fe-Ni base alloy usable in a high pressure environment from a room temperature to a high temperature of about 700°C or a high pressure hydrogen environ or an environment in which both of them are superimposed.SOLUTION: Provided is a high strength Fe-Ni base alloy having a composition comprising 0.040 to 0.10% C, 0.01 to 0.10% Si, 0.010 to 0.030% P, 23.0 to 27.0% Ni, 12.0 to 16.0% Cr, 2.5 to 6.0% W, 1.5 to 2.5% Al and 1.5 to 2.5% Ti, and the balance Fe with the other inevitable impurities, in which, suitably, the content of S is regulated to 0.003% or lower, the content of Mo is regulated to 0.01% or lower and the content of Nb is regulated to 0.01% or lower, comprising 0.040 to 0.055% C and above 0.015% P to 0.025% P, in which the P is included in the crystal grains without involving a &eegr; phase in the metallic structure after aging, and having a size of 0.20 μm or more in an equivalent circle diameter and containing the carbide of either or both by W and Ti in 0.05% or higher in an area ratio. |
