Precipitation hardening stainless steel powder, compound, granulated powder, precipitation hardening stainless steel sintered body, and method for producing precipitation hardening stainless steel sintered body

Abstract

A precipitation hardening stainless steel powder, containing Cr at a concentration A within a range of 15.00 mass % or more and 17.50 mass % or less, Si at a concentration B within a range of 0.30 mass % or more and 1.00 mass % or less, Nb at a concentration C within a range of 0.15 mass % or more and 0.45 mass % or less, Ni at a concentration D within a range of 3.00 mass % or more and 5.00 mass % or less, Mn at a concentration E within a range of 0.05 mass % or more and 1.00 mass % or less, and Cu at a concentration F within a range of 3.00 mass % or more and 5.00 mass % or less, wherein a value of δ defined by the following formula (1) is 10.0 mass % or more and 14.0 mass % or less. δ=3(A+1.5B+0.5C)−2.8(D+0.5E+0.5F)−19.8  (1)

What is claimed is: 
     
         1 . A precipitation hardening stainless steel powder, comprising:
 Cr at a concentration A within a range of 15.00 mass % or more and 17.50 mass % or less;   Si at a concentration B within a range of 0.30 mass % or more and 1.00 mass % or less;   Nb at a concentration C within a range of 0.15 mass % or more and 0.45 mass % or less;   Ni at a concentration D within a range of 3.00 mass % or more and 5.00 mass % or less;   Mn at a concentration E within a range of 0.05 mass % or more and 1.00 mass % or less; and   Cu at a concentration F within a range of 3.00 mass % or more and 5.00 mass % or less, wherein   a value of δ defined by the following formula (1) is 10.0 mass % or more and 14.0 mass % or less:
   δ=3(A+1.5B+0.5C)−2.8(D+0.5E+0.5F)−19.8  (1)
 
   
     
     
         2 . The precipitation hardening stainless steel powder according to  claim 1 , wherein O is contained at a concentration within a range of 0.01 mass % or more and 0.70 mass % or less. 
     
     
         3 . The precipitation hardening stainless steel powder according to  claim 2 , wherein O is contained at a concentration within a range of 0.33 mass % or more and 0.53 mass % or less. 
     
     
         4 . The precipitation hardening stainless steel powder according to  claim 1 , wherein an average particle diameter is 0.50 μm or more and 50.00 μm or less. 
     
     
         5 . A compound, comprising the precipitation hardening stainless steel powder according to  claim 1  and an organic binder. 
     
     
         6 . A granulated powder, comprising the precipitation hardening stainless steel powder according to  claim 1  and an organic binder. 
     
     
         7 . A precipitation hardening stainless steel sintered body, comprising:
 Cr at a concentration A within a range of 15.00 mass % or more and 17.50 mass % or less;   Si at a concentration B within a range of 0.30 mass % or more and 1.00 mass % or less;   Nb at a concentration C within a range of 0.15 mass % or more and 0.45 mass % or less;   Ni at a concentration D within a range of 3.00 mass % or more and 5.00 mass % or less;   Mn at a concentration E within a range of 0.05 mass % or more and 1.00 mass % or less; and   Cu at a concentration F within a range of 3.00 mass % or more and 5.00 mass % or less, wherein   a value of δ defined by the following formula (1) is 10.0 mass % or more and 14.0 mass % or less:
   δ=3(A+1.5B+0.5C)−2.8(D+0.5E+0.5F)−19.8  (1).
 
   
     
     
         8 . A method for producing a precipitation hardening stainless steel sintered body, comprising:
 molding the compound according to  claim 5  or the granulated powder according to  claim 6 , thereby obtaining a molded body; and   firing the molded body, thereby obtaining a sintered body, wherein   a carbon atom concentration in the sintered body is less than a carbon atom concentration in the precipitation hardening stainless steel powder.