Ni-Fe-Cr Alloy
An objective of the present invention is to provide a Ni—Fe—Cr alloy having an excellent intergranular corrosion resistance. A Ni—Fe—Cr alloy of the present embodiment has a chemical composition consisting of, in mass percent, C: 0.005 to 0.015%, Si: 0.05 to 0.50%, Mn: 0.05 to 1.5%, P: 0.030% or less, S: 0.020% or less, Cu: 1.0 to 5.0%, Ni: 30.0 to 45.0%, Cr: 18.0 to 30.0%, Mo: 2.0 to 4.5%, Ti: 0.5 to 2.0%, N: 0.001 to 0.015%, and Al: 0 to 0.50%, with the balance being Fe and impurities. An average grain size d (μm) satisfies Formula (1): d <4.386/(C rel +0.15) (1) where, C rel in Formula (1) is defined by Formula (2): C rel =C−0.125Ti+0.8571N (2) where, symbols of elements in Formula (1) and Formula (2) are to be substituted by contents of corresponding elements (mass %).
1 . A Ni—Fe—Cr alloy comprising a chemical composition consisting of, in mass percent:
C: 0.005 to 0.015%;
Si: 0.05 to 0.50%;
Mn: 0.05 to 1.5%;
P: 0.030% or less;
S: 0.020% or less;
Cu: 1.0 to 5.0%;
Ni: 30.0 to 45.0%;
Cr: 18.0 to 30.0%;
Mo: 2.0 to 4.5%;
Ti: 0.5 to 2.0%;
N: 0.001 to 0.015%; and
Al: 0 to 0.50%, with the balance being Fe and impurities, wherein an average grain size d (μm) satisfies Formula (1):
d< 4.386/(C rel +0.15) (1)
where, C rel in Formula (1) is defined by Formula (2):
C rel =C−0.125Ti+0.8571N (2)
where, symbols of elements in Formula (1) and Formula (2) are to be substituted by contents of corresponding elements (mass %).
2 . The Ni—Fe—Cr alloy according to claim 1 , wherein the chemical composition contains Al: 0.05 to 0.50%.