Ti-CONTAINING FERRITIC STAINLESS STEEL SHEET HAVING GOOD TOUGHNESS, AND FLANGE
A Ti-containing ferritic stainless steel sheet having good toughness has a chemical composition containing, in terms of percentage by mass, from 0.003 to 0.030% of C, 2.0% or less of Si, 2.0% or less of Mn, 0.050% or less of P, 0.040% or less of S, from 10.0 to 19.0% of Cr, 0.030% or less of N, 4(C+N) or more and 0.80% or less of Ti, and from 0.010 to 0.20% of Al, furthermore one or more of 1.50% or less of Mo and 0.0030% or less of B if necessary, with the balance of Fe and unavoidable impurities, and has a content R (% by mass) of an extraction residue recovered by an electrolytic extraction method and contents of C and N in the steel that satisfy the following expression (1): R>5.0C+4.4N−0.025 (1).
1 . A Ti-containing ferritic stainless steel sheet having a chemical composition containing, in terms of percentage by mass, from 0.003 to 0.030% of C, 2.0% or less of Si, 2.0% or less of Mn, 0.050% or less of P, 0.040% or less of S, from 10.0 to 19.0% of Cr, 0.030% or less of N, 4(C+N) or more and 0.80% or less of Ti, and from 0.010 to 0.20% of Al, with the balance of Fe and unavoidable impurities, and having a content R (% by mass) of an extraction residue recovered by an electrolytic extraction method and contents of C and N in the steel that satisfy the following expression (1):
R>5.0C+4.4N−0.025 (1)
wherein in the lower limit of the Ti content and the expression (1), C and N represent the contents of C and N in the steel in terms of percentage by mass respectively.
2 . The Ti-containing ferritic stainless steel sheet according to claim 1 , wherein in the chemical composition, the C content is from 0.007 to 0.030% by mass.
3 . The Ti-containing ferritic stainless steel sheet according to claim 1 , wherein the Ti-containing ferritic stainless steel sheet has the chemical composition further containing, in terms of percentage by mass, 1.50% or less of Mo.
4 . The Ti-containing ferritic stainless steel sheet according to claim 1 , wherein the Ti-containing ferritic stainless steel sheet has the chemical composition further containing, in terms of percentage by mass, 0.0050% or less of B.
5 . The Ti-containing ferritic stainless steel sheet according to claim 1 , wherein the Ti-containing ferritic stainless steel sheet has a sheet thickness of from 5.0 to 11.0 mm.
6 . A flange using the Ti-containing ferritic stainless steel sheet according to claim 1 .
7 . The flange according to claim 6 , wherein the flange is a flange for an exhaust gas flow path.
8 . The flange according to claim 6 , wherein the flange is a flange for an automobile exhaust gas flow path.