Austenitic Stainless Steel

Abstract

where symbols of elements in Formula (1) are to be substituted by contents of corresponding elements (mass %).

1 . An austenitic stainless steel comprising a chemical composition consisting of, in mass %:
 C: 0.030% or less;   Si: 0.10 to 1.00%;   Mn: 0.20 to 2.00%;   P: 0.040% or less;   S: 0.010% or less;   Cr: 16.0 to 25.0%;   Ni: 10.0 to 30.0%;   Mo: 0.1 to 5.0%;   Nb: 0.20 to 1.00%;   N: 0.050 to 0.300%;   sol.Al: 0.0005 to 0.100%;   B: 0.0010 to 0.0080%;   Cu: 0 to 5.0%;   W: 0 to 5.0%;   Co: 0 to 1.0%;   V: 0 to 1.00%;   Ta: 0 to 0.2%;   Hf: 0 to 0.20%;   Ca: 0 to 0.010%;   Mg: 0 to 0.010%; and   rare earth metals: 0 to 0.10%,   with the balance being Fe and impurities,   and satisfying Formula (1):
   B+0.004−0.9C+0.017Mo 2 ≥0  (1)
 
   
       where symbols of elements in Formula (1) are to be substituted by contents of corresponding elements (mass %). 
     
     
         2 . The austenitic stainless steel according to  claim 1 , wherein the chemical composition contains one or more elements selected from the group consisting of:
 Cu: 0.1 to 5.0%;   W: 0.1 to 5.0%; and   Co: 0.1 to 1.0%.   
     
     
         3 . The austenitic stainless steel according to  claim 1 , wherein the chemical composition contains one or more elements selected from the group consisting of:
 V: 0.1 to 1.00%;   Ta: 0.01 to 0.2%; and   Hf: 0.01 to 0.20%.   
     
     
         4 . The austenitic stainless steel according  claim 1 , wherein the chemical composition contains one or more elements selected from the group consisting of:
 Ca: 0.0005 to 0.010%;   Mg: 0.0005 to 0.010%; and   rare earth metals: 0.001 to 0.10%.   
     
     
         5 . The austenitic stainless steel according to  claim 1 , wherein the chemical composition contains
 Cu: 0 to 1.9%.   
     
     
         6 . The austenitic stainless steel according to  claim 2 , wherein the chemical composition contains one or more elements selected from the group consisting of:
 V: 0.1 to 1.00%;   Ta: 0.01 to 0.2%; and   Hf: 0.01 to 0.20%.   
     
     
         7 . The austenitic stainless steel according to  claim 2 , wherein the chemical composition contains one or more elements selected from the group consisting of:
 Ca: 0.0005 to 0.010%;   Mg: 0.0005 to 0.010%; and   rare earth metals: 0.001 to 0.10%.   
     
     
         8 . The austenitic stainless steel according to  claim 3 , wherein the chemical composition contains one or more elements selected from the group consisting of:
 Ca: 0.0005 to 0.010%;   Mg: 0.0005 to 0.010%; and   rare earth metals: 0.001 to 0.10%.   
     
     
         9 . The austenitic stainless steel according to  claim 6 , wherein the chemical composition contains one or more elements selected from the group consisting of:
 Ca: 0.0005 to 0.010%;   Mg: 0.0005 to 0.010%; and   rare earth metals: 0.001 to 0.10%.