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:
Feb. 26, 2013
Filed:
Jun. 29, 2011
Nao Yoshihara, Kobe, JP;
Fujio Koizumi, Kobe, JP;
Hirokazu Inoue, Kobe, JP;
Katsuya Takaoka, Kobe, JP;
Shoji Miyazaki, Kobe, JP;
Sayaka Nagamatsu, Kobe, JP;
Nao Yoshihara, Kobe, JP;
Fujio Koizumi, Kobe, JP;
Hirokazu Inoue, Kobe, JP;
Katsuya Takaoka, Kobe, JP;
Shoji Miyazaki, Kobe, JP;
Sayaka Nagamatsu, Kobe, JP;
Kobe Steel, Ltd., Kobe-shi, JP;
Abstract
The steel wire material for a spring of the invention contains; C: 0.37-0.54%, Si: 1.7-2.30%, Mn: 0.1-1.30%, Cr: 0.15-1.1%, Cu: 0.15-0.6%, Ti: 0.010-0.1%, Al: 0.003-0.05%, and the balance including iron with inevitable impurities, wherein ferrite decarburized layer depth is 0.01 mm or less, whole decarburized layer depth is 0.20 mm or less, and fracture reduction of area is 25% or more. It alternately may contain; C: 0.38-0.47%, Si: 1.9-2.5%, Mn: 0.6-1.3%, Ti: 0.05-0.15%, Al: 0.003-0.1%, and the balance including iron with inevitable impurities, wherein ferrite decarburized layer depth is 0.01 mm or less.