公开(公告)号：US20230366070A1

公开(公告)日：2023-11-16

申请号：US18044249

申请日：2021-10-29

Applicant: NIPPON STEEL CORPORATION

Inventor： Shinji YOSHIDA ,  Yuji ARAI ,  Hiroyuki FUJI

IPC: C22C38/34 ,  C22C38/00 ,  C22C38/04 ,  C22C38/06 ,  C22C38/22 ,  C22C38/24 ,  C22C38/28 ,  C22C38/32 ,  C21D9/08

CPC classification number: C22C38/34 ,  C22C38/001 ,  C22C38/002 ,  C22C38/04 ,  C22C38/06 ,  C22C38/22 ,  C22C38/24 ,  C22C38/28 ,  C22C38/32 ,  C21D9/08

Abstract: The steel material according to the present disclosure contains, in mass %, C: 0.20 to 0.45%, Si: 1.36 to 3.20%, Mn: 0.02 to 1.00%, P: 0.025% or less, S: 0.0100% or less, Al: 0.005 to 0.100%, Cr: 0.20 to 1.50%, Mo: 0.36 to 1.50%, V: 0.01 to 0.90%, Ti: 0.002 to 0.050%, B: 0.0001 to 0.0050%, N: 0.0100% or less, and O: 0.0100% or less, and satisfies Formula (1). A yield strength σYS is 758 MPa or more. The yield strength σYS and a dislocation density ρ satisfy Formula (2).


27×Mn+9×Cr−14×Mo−770×C2+760×C−11×Si2+4×Si>85   (1)



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