Alloy material

Abstract

An alloy material that has excellent intergranular corrosion resistance is provided. An alloy material according to the present disclosure has a chemical composition containing, in mass %, C: 0.005 to 0.020%, Si: 0.05 to 0.50%, Mn: 0.05 to 1.00%, P: 0.030% or less, S: 0.0100% or less, Cu: 1.5 to 3.0%, Ni: 35.0 to 50.0%, Cr: 20.0 to 30.0%, Mo: 2.5 to 4.0%, Co: 0.01 to 0.80%, W: 0.01 to 0.30%, Ca: 0.0050% or less, N: 0.001 to 0.015%, Al: 0.20% or less, B: 0.0030% or less, Sn: 0.050% or less, and Ti: 0.40 to 0.90%, with the balance being Fe and impurities, in which the total content of Ti, Nb, V, Zr, Hf, and Ta is 0.420 to 1.000%. The number density of fine nitrogen-containing precipitates at grain boundaries of the alloy material is 20 /μm or less.

1 . An alloy material having a chemical composition consisting of, in mass %,
 C: 0.005 to 0.020%,   Si: 0.05 to 0.50%,   Mn: 0.05 to 1.00%,   P: 0.030% or less,   S: 0.0100% or less,   Cu: 1.5 to 3.0%,   Ni: 35.0 to 50.0%,   Cr: 20.0 to 30.0%,   Mo: 2.5 to 4.0%,   Co: 0.01 to 0.80%,   W: 0.01 to 0.30%,   Ca: 0.0050% or less,   N: 0.001 to 0.015%,   Al: 0.20% or less,   B: 0.0030% or less,   Sn: 0.050% or less,   Ti: 0.40 to 0.90%,   Nb: 0 to 0.150%,   V: 0 to 0.150%,   Zr: 0 to 0.150%,   Hf: 0 to 0.150%, and   Ta: 0 to 0.150%,   with the balance being Fe and impurities,   wherein:   a total content of Ti, Nb, V, Zr, Hf, and Ta is 0.420 to 1.000%, and   a number density of nitrogen-containing precipitates having a major axis of 10 to 100 nm at grain boundaries of the alloy material is 20 /μm or less.   
     
     
         2 . The alloy material according to  claim 1 , wherein the chemical composition contains one or more elements selected from a group consisting of:
 Nb: 0.001 to 0.150%,   V: 0.001 to 0.150%,   Zr: 0.001 to 0.150%,   Hf: 0.001 to 0.150%, and   Ta: 0.001 to 0.150%.   
     
     
         3 . The alloy material according to  claim 1 , wherein:
 the alloy material is an alloy pipe.   
     
     
         4 . The alloy material according to  claim 2 , wherein:
 the alloy material is an alloy pipe.