Austenitic stainless steel

Abstract

An austenitic stainless steel, which comprises by mass percent, C: not more than 0.10%, Si: 0.01 to 1.0%, Mn: 0.01 to 2%, Cr: 16 to 18%, Ni: more than 10% to less than 14%, Mo: more than 2.0% to not more than 3.0%, N: 0.03 to 0.10%, one or more elements selected from V, Nb and Ti satisfying the following formulas (1) and (2), 0.0013≦(V/51)+(Nb/93)+(Ti/48)≦0.0025  (1), {(C/12)+(N/14)}−{(V/51)+(Nb/93)+(Ti/48)}≦0.0058  (2), wherein each element symbol in the formulas (1) and (2) represents the content (by mass %) of the element concerned, with the balance being Fe and impurities, wherein the content of P is not more than 0.04% and the content of S is not more than 0.003% among the impurities, has excellent corrosion resistance, in particular, excellent intergranular corrosion resistance. The preferable contents of Nb and Ti are not more than 0.030% and not more than 0.050%, respectively.

1 . An austenitic stainless steel, which comprises by mass percent, C: not more than 0.10%, Si: 0.01 to 1.0%, Mn: 0.01 to 2%, Cr: 16 to 18%, Ni: more than 10% to less than 14%, Mo: more than 2.0% to not more than 3.0%, N: 0.03 to 0.10%, one or more elements selected from V, Nb and Ti satisfying the following formulas (1) and (2), with the balance being Fe and impurities, wherein the content of P is not more than 0.04% and the content of S is not more than 0.003% among the impurities:
   0.0013≦(V/51)+(Nb/93)+(Ti/48)≦0.0025  (1),     {(C/12)+(N/14)}−{(V/51)+(Nb/93)+(Ti/48)}≦0.0058  (2),   
     wherein each element symbol in the formulas (1) and (2) represents the content (by mass %) of the element concerned. 
   
   
       2 . The austenitic stainless steel according to  claim 1 , wherein the content of Nb is not more than 0.030% or the content of Ti is not more than 0.050%, or, the content of Nb is not more than 0.030% and the content of Ti is not more than 0.050%, by mass percent.