The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 24, 2020
Filed:
Jul. 24, 2014
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
Kenji Kobayashi, Tokyo, JP;
Yusaku Tomio, Tokyo, JP;
NIPPON STEEL CORPORATION, Tokyo, JP;
Abstract
There is provided a high-strength steel material for oil well having a chemical composition consisting, by mass percent, of C: 0.60-1.4%, Si: 0.05-1.00%, Mn: 12-25%, Al: 0.003-0.06%, P: ≤0.03%, S: ≤0.03%, N: <0.1%, Cr: ≥0% and <5.0%, Mo: ≥0% and <3.0%, Cu: ≤0% and <1.0%, Ni: ≥0% and <1.0%, V: 0-0.5%, Nb: 0-0.5%, Ta: 0-0.5%, Ti: 0-0.5%, Zr: 0-0.5%, Ca: ≥0% and <0.005%, Mg: ≥0% and <0.005%, B: 0-0.015%, the balance: Fe and impurities, wherein Nieq [=Ni+30C+0.5Mn] is 27.5 or higher, a metal micro-structure is a structure consisting mainly of an FCC structure, a total volume fraction of ferrite and α' martensite is less than 0.10%, and a yield strength is 862 MPa or higher.