	US 11,667,986 B2
	Ferritic stainless steel and method for manufacturing same, ferritic stainless steel sheet and method for manufacturing same, and fuel cell member
Masaharu Hatano, Tokyo (JP); Mitsuki Sugeoi, Tokyo (JP); and Takumi Nishimoto, Tokyo (JP)
Assigned to NIPPON STEEL STAINLESS STEEL CORPORATION, Tokyo (JP)
Appl. No. 17/40,870
Filed by NIPPON STEEL STAINLESS STEEL CORPORATION, Tokyo (JP)
PCT Filed Mar. 26, 2019, PCT No. PCT/JP2019/012843 § 371(c)(1), (2) Date Sep. 23, 2020, PCT Pub. No. WO2019/189174, PCT Pub. Date Oct. 3, 2019.
Claims priority of application No. JP2018-060883 (JP), filed on Mar. 27, 2018; application No. JP2018-060885 (JP), filed on Mar. 27, 2018; and application No. JP2018-060886 (JP), filed on Mar. 27, 2018.
Prior Publication US 2021/0025022 A1, Jan. 28, 2021
Int. Cl. C22C 38/06 (2006.01); C21D 9/46 (2006.01); C21D 6/00 (2006.01); C21D 8/02 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/42 (2006.01); C22C 38/44 (2006.01); C22C 38/46 (2006.01); C22C 38/48 (2006.01); C22C 38/50 (2006.01); C22C 38/52 (2006.01); C22C 38/54 (2006.01); C22C 38/58 (2006.01)

CPC C21D 9/46 (2013.01) [C21D 6/004 (2013.01); C21D 6/005 (2013.01); C21D 6/008 (2013.01); C21D 8/0205 (2013.01); C21D 8/0236 (2013.01); C21D 8/0273 (2013.01); C21D 8/0278 (2013.01); C22C 38/001 (2013.01); C22C 38/002 (2013.01); C22C 38/005 (2013.01); C22C 38/008 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/42 (2013.01); C22C 38/44 (2013.01); C22C 38/46 (2013.01); C22C 38/48 (2013.01); C22C 38/50 (2013.01); C22C 38/52 (2013.01); C22C 38/54 (2013.01); C22C 38/58 (2013.01); C21D 2211/005 (2013.01)]

9 Claims

1. Ferritic stainless steel, comprising, by mass %:

Cr: 12.0% to 16.0%;

C: 0.020% or less;

Si: 1.10% or more and 2.50% or less;

Mn: 1.00% or less;

P: 0.050% or less;

S: 0.0030% or less;

Al: 1% or more and 2.50% or less;

N: 0.030% or less;

Nb: 0.001% to 1.00%;

Ni: 0% to 1.0%;

Cu: 0% to 1.0%;

Mo: 0% to 1.0%;

Sb: 0% to 0.5%;

W: 0% to 1.0%;

Co: 0% to 0.5%;

V: 0% to 0.5%;

Ti: 0% to 0.5%;

Zr: 0% to 0.5%;

La: 0% to 0.1%;

Y: 0% to 0.1%;

Hf: 0% to 0.1%;

REM: 0 to 0.1%;

one or more of B: 0.0200% or less, Sn: 0.20% or less, Ga: 0.0200% or less, Mg: 0.0200% or less, and Ca: 0.0100% or less; and a balance being Fe and impurities,

wherein Expression (1) is satisfied,

10(B+Ga)+Sn+Mg+Ca>0.020 (1)

where each of the element symbols in Expression (1) indicates the content, in mass %, each of the elements in the steel, and

wherein a concentration of Nb at a crystal grain boundary is within a range of 3.0% to 10% by mass %.