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:
Aug. 01, 2017
Filed:
Feb. 04, 2013
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
Yuya Gyotoku, Tokyo, JP;
Masayuki Horimoto, Tokyo, JP;
Hideki Imataka, Tokyo, JP;
Kosuke Tanaka, Tokyo, JP;
NIPPON STEEL & SUMITOMO METAL CORPORATION, Tokyo, JP;
Abstract
A steel material for nitriding has a composition comprising, by mass percent, C: more than 0.15% and not more than 0.35%, Si≦0.20%, Mn: 0.10 to 2.0%, P≦0.030%, S≦0.050%, Cr: 0.80 to 2.0%, V: 0.10 to 0.50%, Al: 0.01 to 0.06%, N≦0.0080%, O≦0.0030%, and optionally one or more elements of Mo, Cu, Ni, Ti, Nb, Zr, Pb, Ca, Bi, Te, Se and Sb, the balance being Fe and impurities. The composition satisfies the conditions of [20≦(669.3×logC−1959.6×logN−6983.3)×(0.067×Mo+0.147×V)≦80] and [140×Cr+125×Al+235×V≧160]. The microstructure is a ferritic-pearlitic structure, a ferritic-bainitic structure, or a ferritic-pearlitic-bainitic structure. The area fraction of ferrite is 20% or more and the precipitate content of V is 0.10% or less.