Ni-BASED ALLOY AND METHOD FOR MANUFACTURING THE SAME, AND Ni-BASED ALLOY MEMBER

Abstract

A Ni-based alloy consisting of, in terms of mass %: 0.10%<C≤0.30%; Si≤0.50%; Mn≤0.50%; P≤0.030%; S≤0.010%; Cu≤3.00%; 30.0%≤Cr≤39.0%; Mo≤3.00%; Fe≤3.00%; 2.00%≤Al≤5.00%; O≤0.0100%; N≤0.050%; Nb≤0.50%; V≤0.50%; Ti≤0.50%; Ta≤0.50%; W≤0.50%; and at least one selected from the group consisting of 0.0010%≤B≤0.0100%, 0.0010%≤Mg≤0.0100%, and 0.0010%≤Ca≤0.0100%, with the balance being Ni and unavoidable impurities, in which the alloy comprises an austenite phase having an average grain diameter of 50.0 μm or less, a M23C6-type carbide having an average circle equivalent particle diameter of 1.0 μm or more, and a massive α-Cr phase having an average circle equivalent particle diameter of 10.0 μm or less.

What is claimed is: 
     
         1 . A Ni-based alloy consisting of:
 0.10 mass %<C≤0.30 mass %;   Si≤0.50 mass %;   Mn≤0.50 mass %;   P≤0.030 mass %;   S≤0.010 mass %;   Cu≤3.00 mass %;   30.0 mass %≤Cr≤39.0 mass %;   Mo≤3.00 mass %;   Fe≤3.00 mass %;   2.00 mass %≤Al≤5.00 mass %;   O≤0.0100 mass %;   N≤0.050 mass %;   Nb≤0.50 mass %;   V≤0.50 mass %;   Ti≤0.50 mass %;   Ta≤0.50 mass;   W≤0.50 mass %; and   at least one element selected from the group consisting of 0.0010 mass %≤B≤0.0100 mass %, 0.0010 mass %≤Mg≤0.0100 mass %, and 0.0010 mass %≤Ca≤0.0100 mass %,   with the balance being Ni and unavoidable impurities, wherein   the Ni-based alloy comprises
 an austenite phase (γ phase) having an average grain diameter of 50.0 μm or less, 
 a M 23 C 6 -type carbide having an average circle equivalent particle diameter of 1.0 μm or more, and 
 a massive α-Cr phase having an average circle equivalent particle diameter of 10.0 μm or less. 
   
     
     
         2 . A Ni-based alloy member comprising the Ni-based alloy according to  claim 1 . 
     
     
         3 . A Ni-based alloy consisting of:
 0.10 mass %<C≤0.30 mass %;   Si≤0.50 mass %;   Mn≤0.50 mass %;   P≤0.030 mass %;   S≤0.010 mass %;   Cu≤3.00 mass %;   30.0 mass %≤Cr≤39.0 mass %;   Mo≤3.00 mass %;   Fe≤3.00 mass %;   2.00 mass %≤Al≤5.00 mass %;   O≤0.0100 mass %;   N≤0.050 mass %;   Nb≤0.50 mass %;   V≤0.50 mass %;   Ti≤0.50 mass %;   Ta≤0.50 mass;   W≤0.50 mass %; and   at least one element selected from the group consisting of 0.0010 mass %≤B≤0.0100 mass %, 0.0010 mass %≤Mg≤0.0100 mass %, and 0.0010 mass %≤Ca≤0.0100 mass %,   with the balance being Ni and unavoidable impurities, wherein   the Ni-based alloy comprises
 a cellular structure, 
 a M 23 C 6 -type carbide having an average circle equivalent particle diameter of 1.0 μm or more, and 
 a massive α-Cr phase having an average circle equivalent particle diameter of 10.0 μm or less, 
   wherein the cellular structure is a structure in which a lamellar structure of the α-Cr phase and a γ phase in which a γ′ phase is precipitated is formed in a state of cell on an entire inside of an austenite phase,   wherein the Ni-based alloy has a 0.2% proof stress at 25° C. of 1300 MPa or more, and   wherein the Ni-based alloy has an absorption energy at 25° C. of 40 J (10 R notch) or more.   
     
     
         4 . A Ni-based alloy member comprising the Ni-based alloy according to  claim 3 . 
     
     
         5 . A method for manufacturing a Ni-based alloy, the method comprising:
 a first step of obtaining an ingot by melting and casting a raw material blended to have a predetermined composition;   a second step of obtaining a primary hot-worked product by subjecting the ingot to primary hot working;   a third step of obtaining a homogenized heat-treated product by subjecting the primary hot-worked product to homogenization heat treatment;   a fourth step of obtaining a secondary hot-worked product by subjecting the homogenized heat-treated product to secondary hot working; and   a fifth step of obtaining the Ni-based alloy according to  claim 1  by subjecting the secondary hot-worked product to solution heat treatment.   
     
     
         6 . The method for manufacturing a Ni-based alloy according to  claim 5 , the method further comprising:
 a seventh step of obtaining the Ni-based alloy according to  claim 3  by subjecting the Ni-based alloy after the solution heat treatment to aging treatment.