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:
Oct. 29, 2019
Filed:
Jan. 27, 2016
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
NIPPON STEEL CORPORATION, Tokyo, JP;
Abstract
A steel wire for a non heat-treated mechanical part includes, as a chemical composition, by mass %, a predetermined amount of C, Si, Mn, Cr, Mo, Ti, Al, B, Nb, and V, and limited P, S, N, and O and a remainder of Fe and impurities; in which a structure includes, by volume %, a bainite of greater than or equal to 75×[C %]+25, and a remainder of one or more of a ferrite and a pearlite when an amount of C is set to [C %] by mass %; when an average aspect ratio of a bainite block in a second surface layer area of the steel wire is set as R1, the R1 is greater than or equal to 1.2; when an average grain size of a bainite block in a third surface layer area of the steel wire is set to Pμm, and an average grain size of a bainite block in a third center portion of the steel wire is set to Pμm, the Psatisfies Expression (c), and the Pand the Psatisfy Expression (d), a standard deviation of a grain size of the bainite block in the structure is less than or equal to 8.0 μm; and a tensile strength is in a range of 800 MPa to 1600 MPa,≤20/1  (c),≤0.95  (d).