US 12,442,054 B2
Austenitic stainless cast steel and method for producing austenitic stainless cast steel
Tadaaki Nakamura, Tokyo (JP); Nobuhiko Saito, Tokyo (JP); Nobuyoshi Komai, Tokyo (JP); Keita Hashimoto, Tokyo (JP); and Yuya Konno, Tokyo (JP)
Assigned to MITSUBISHI HEAVY INDUSTRIES ENGINE & TURBOCHARGER, LTD., Kanagawa (JP)
Appl. No. 18/018,021
Filed by MITSUBISHI HEAVY INDUSTRIES ENGINE & TURBOCHARGER, LTD., Sagamihara (JP)
PCT Filed Sep. 6, 2021, PCT No. PCT/JP2021/032593
§ 371(c)(1), (2) Date Jan. 25, 2023,
PCT Pub. No. WO2022/113466, PCT Pub. Date Jun. 2, 2022.
Claims priority of application No. 2020-197385 (JP), filed on Nov. 27, 2020.
Prior Publication US 2023/0272496 A1, Aug. 31, 2023
Int. Cl. C21D 6/02 (2006.01); C21D 6/00 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/44 (2006.01); C22C 38/48 (2006.01)
CPC C21D 6/02 (2013.01) [C21D 6/004 (2013.01); C22C 38/002 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/44 (2013.01); C22C 38/48 (2013.01); C21D 2211/001 (2013.01); C21D 2211/004 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A cast austenitic stainless steel,
wherein, in a cross section when heated at 1000° C.,
an average number Nc per unit area of carbides having an equivalent circle diameter of 500 nm or larger in a center portion of an austenite crystal grain is 6.0×10−2 particles/μm2 or more, and
when an average number per unit area of the carbides having an equivalent circle diameter of 500 nm or larger in a vicinity of a grain boundary in an austenite crystal grain is represented as Ngb, Ngb/Nc is 1.30 or less.