Ferritic stainless-steel sheet

Abstract

In order to provide a ferritic stainless-steel sheet having excellent formability, there is provided a forming method in which a ferritic stainless-steel sheet is subjected to rectangular drawing forming to a desired forming depth by press forming using a punch and a die, and a ferritic stainless-steel sheet that contains C, Si, Mn, P, S, Cr, N, Al, O, Ti, Nb, Sn, and Zr, has a component composition that satisfies the following Formula (1) and Formula (2), has a sheet thickness of 1.0 mm or less and a limiting drawing ratio in cylindrical cup drawing of 2.30 or more is used,(0.4×Al+0.5×Zr+0.1×Ti)/O≥12.0  (1)0.6×Cr+15×Sn+8×Al≥10.0  (2).

1 . A ferritic stainless-steel sheet comprising, in mass %,
 C: 0.0200% or less,   Si: 0.70% or less,   Mn: 1.00% or less,   P: 0.030% or less,   S: 0.005% or less,   Cr: 11.0 to 19.50%,   N: 0.020% or less,   Al: 0.005 to 0.100%,   O: 0.0050% or less,   Ti: 0.03 to 0.20%,   Nb: 0.010 to 0.300%,   Sn: 0.001 to 0.300%, and   Zr: 0.001 to 0.080%, with   a remainder of Fe and impurities,   and having a component composition that satisfies the following Formula (1) and Formula (2), having a sheet thickness of 1.0 mm or less, and a limiting drawing ratio in cylindrical cup drawing of 2.30 or more:
   (0.4×Al+0.5×Zr+0.1×Ti)/O≥12.0  (1)
 
   0.6×Cr+15×Sn+8×Al≥10.0  (2)
 
   where, element symbols in Formula (1) and Formula (2) represent the amount (mass %) of the elements in the ferritic stainless-steel sheet.   
     
     
         2 . The ferritic stainless-steel sheet according to  claim 1 , comprising, in mass %, one or more of Mo: 0.05 to 0.50%, Ni: 0.05 to 0.50%, and Cu: 0.01 to 1.00%, in place of some Fe. 
     
     
         3 . The ferritic stainless-steel sheet according to  claim 1 , comprising, in mass %, one or more of B: 0.0003 to 0.0050%, Ga: 0.0001 to 0.2%, and W: 0.001 to 0.300%, in place of some Fe. 
     
     
         4 . The ferritic stainless-steel sheet according to  claim 1 ,
 wherein the average Lankford value is 1.8 or more, and the planar anisotropy (Δr) of the Lankford value is 0.5 or more.   
     
     
         5 . The ferritic stainless-steel sheet according to  claim 2 , comprising, in mass %, one or more of B: 0.0003 to 0.0050%, Ga: 0.0001 to 0.2%, and W: 0.001 to 0.300%, in place of some Fe. 
     
     
         6 . The ferritic stainless-steel sheet according to  claim 2 ,
 wherein the average Lankford value is 1.8 or more, and the planar anisotropy (Δr) of the Lankford value is 0.5 or more.   
     
     
         7 . The ferritic stainless-steel sheet according to  claim 3 ,
 wherein the average Lankford value is 1.8 or more, and the planar anisotropy (Δr) of the Lankford value is 0.5 or more.   
     
     
         8 . The ferritic stainless-steel sheet according to  claim 5 ,
 wherein the average Lankford value is 1.8 or more, and the planar anisotropy (Δr) of the Lankford value is 0.5 or more.