Publication number: 20190292618
Abstract: Provided herein is a high-strength seamless stainless steel pipe. The high-strength seamless stainless steel pipe contains, in mass %, C: 0.05% or less, Si: 0.5% or less, Mn: 0.15 to 1.0%, P: 0.030% or less, S: 0.005% or less, Cr: 14.5 to 17.5%, Ni: 3.0 to 6.0%, Mo: 2.7 to 5.0%, Cu: 0.3 to 4.0%, W: 0.1 to 2.5%, V: 0.02 to 0.20%, Al: 0.10% or less, N: 0.15% or less, and the balance being Fe and unavoidable impurities. C, Si, Mn, Cr, Ni, Mo, Cu, and N satisfy a specific formula. Cu, Mo, W, Cr, and Ni satisfy another specific formula. The high-strength seamless stainless steel pipe has more than 45% martensite phase, 10 to 45% ferrite phase, and 30% or less retained austenite phase. The total amount of precipitated Cr, precipitated Mo, and precipitated W is 0.75 mass % or less.
Type:
Application
Filed:
June 14, 2017
Publication date:
September 26, 2019
Applicant:
JFE Steel Corporation
Inventors:
Kenichiro EGUCHI, Yasuhide ISHIGURO
Publication number: 20190136337
Abstract: A high strength stainless steel seamless pipe for oil country tubular goods which is excellent in hot workability, has a high strength, suppresses scattering in the strength, and has excellent carbon dioxide corrosion resistance. The steel pipe has a yield strength of 655 MPa or more, and a chemical composition comprising, by mass%, C: 0.005 to 0.05%, Si: 0.05 to 0.50%, Mn: 0.20 to 1.80%, P: 0.030% or less, S: 0.005% or less, Cr: 12.0 to 17.0%, Ni: 4.0 to 7.0%, Mo: 0.5 to 3.0%, Al: 0.005 to 0.10%, V: 0.005 to 0.20%, Co: 0.01 to 1.0%, N: 0.005 to 0.15%, and 0: 0.010% or less with the balance being Fe and inevitable impurities. Cr, Ni, Mo, Cu, and C satisfy a specified expression, and Cr, Mo, Si, C, Mn, Ni, Cu, and N satisfy another specified expression.
Type:
Application
Filed:
December 16, 2016
Publication date:
May 9, 2019
Applicant:
JFE STEEL CORPORATION
Inventors:
Kenichiro EGUCHI, Yasuhide ISHIGURO