Cr-based stainless steel having excellent hydrogen embrittlement resistance

Abstract

A Cr-based stainless steel sheet includes: 0.020 mass % or less of C; 1.00 mass % or less of Si; 1.00 mass % or less of Mn; 0.040 mass % or less of P; 0.0030 mass % or less of S; 10.0 to 18.0 mass % of Cr; 0.020 mass % or less of N; 0.10 mass % or less of Al; and one or both of 0.5 mass % or less of Nb and 0.5 mass % or less of Ti; in which a texture in a sheet surface satisfies (i) and (ii) below. (i) In the sheet surface, an area ratio of crystal grains ({211}±10-degree-oriented grains) whose orientation difference between a normal direction of the surface and a {211}-plane orientation is 10 degrees or less is less than 30%. (ii) For the {211}±10-degree-oriented grains, a length in a rolling direction and a length in a sheet width direction are each less than 0.15 mm on average.

1 . A Cr-based stainless steel sheet comprising:
 0.020 mass % or less of C;   1.00 mass % or less of Si;   1.00 mass % or less of Mn;   0.040 mass % or less of P;   0.0030 mass % or less of S;   10.0 to 18.0 mass % of Cr;   0.020 mass % or less of N;   0.10 mass % or less of Al;   one or both of 0.5 mass % or less of Nb and 0.5 mass % or less of Ti;   0 to 0.3 mass % of Sn;   0 to 0.005 mass % of B;   0 to 1 mass % of Ni;   0 to 1 mass % of Cu;   0 to 1 mass % of Mo;   0.2 mass % or less of Sb;   0 to 0.5 mass % of V;   0 to 0.5 mass % of W;   0 to 0.5 mass % of Zr;   0 to 0.5 mass % of Co;   0 to 0.005 mass % of Mg;   0 to 0.005 mass % of Ca;   0 to 0.020 mass % of Ga;   0 to 0.1 mass % of La;   0 to 0.1 mass % of Y;   0 to 0.1 mass % of Hf;   0 to 0.1 mass % of REM; and   a balance consisting of Fe and impurities,
 wherein a texture in a sheet surface of the Cr-based stainless steel sheet satisfies (i) and 
   (ii) below,   (i) in the sheet surface, an area ratio of crystal grains (hereinafter referred to as “{211}±10-degree-oriented grains”) whose orientation difference between a normal direction of a surface of the steel sheet and a {211}-plane orientation is 10 degrees or less is less than 30%, and   (ii) for the {211}±10-degree-oriented grains defined in (i), a length in a rolling direction and a length in a sheet width direction are each less than 0.15 mm on average.   
     
     
         2 . The Cr-based stainless steel sheet according to  claim 1 , further comprising 0.001 to 0.3 mass % of Sn and 0.005 mass % or less of B, wherein the Cr-based stainless steel sheet satisfies Formula (1) below,
   Si+0.5 Mn+10 P+5 Nb+2 Ti<2.00   Formula (1),
   where in the formula, symbols of elements indicate contents (mass %) of the respective elements.   
     
     
         3 . The Cr-based stainless steel sheet according to  claim 1 , further comprising one or more selected from 1 mass % or less of Ni, 1 mass % or less of Cu, 1 mass % or less of Mo, 0.2 mass % or less of Sb, 0.5 mass % or less of V, 0.5 mass % or less of W, 0.5 mass % or less of Zr, 0.5 mass % or less of Co, 0.005 mass % or less of Mg, 0.005 mass % or less of Ca, 0.020 mass % or less of Ga, 0.1 mass % or less of La, 0.1 mass % or less of Y, 0.1 mass % or less of Hf, and 0.1 mass % or less of REM. 
     
     
         4 . The Cr-based stainless steel sheet according to  claim 1 , wherein the Cr-based stainless steel sheet is used for metals for high pressure hydrogen gaseous equipment.