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:
Jun. 23, 2015
Filed:
Dec. 03, 2007
Tomoko Sugimura, Kobe, JP;
Koichi Sakamoto, Kobe, JP;
Tomoko Sugimura, Kobe, JP;
Koichi Sakamoto, Kobe, JP;
Kobe Steel, Ltd., Kobe-shi, JP;
Abstract
A Si-killed steel wire rod for obtaining a spring excellent in fatigue properties and a spring excellent in fatigue properties obtained from the steel wire rod are provided. The Si-killed steel wire rod of the present invention contains Sr: 0.03-20 ppm (means 'mass ppm', hereinafter the same), Al: 1-30 ppm and Si: 0.2-4% (means 'mass %', hereinafter the same) respectively, and contains Mg and/or Ca by a range of 0.5-30 ppm in total. Also, in the Si-killed steel wire rod of the present invention, oxide-based inclusions present in the wire rod contain SiO: 30-90%, AlO: 2-50%, MgO: 35% or below (not inclusive of 0%), CaO: 50% or below (not inclusive of 0%), MnO: 20% or below (not inclusive of 0%) and SrO: 0.2-15% respectively, and total content of (CaO+MgO) is 3% or above. A spring excellent in fatigue properties can be obtained by forming the spring from such steel wire rod.