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:
May. 29, 2012
Filed:
Mar. 27, 2008
Steel for high-cleanliness spring with excellent fatigue characteristics and high-cleanliness spring
Tomoko Sugimura, Kobe, JP;
Koichi Sakamoto, Kobe, JP;
Yoshio Fukuzaki, Kobe, JP;
Atsuhiko Yoshida, Kobe, JP;
Takeshi Inoue, Kobe, JP;
Tomoko Sugimura, Kobe, JP;
Koichi Sakamoto, Kobe, JP;
Yoshio Fukuzaki, Kobe, JP;
Atsuhiko Yoshida, Kobe, JP;
Takeshi Inoue, Kobe, JP;
Kobe Steel, Ltd., Kobe-shi, JP;
Abstract
An object of this invention is to provide a steel for high-cleanliness spring which is useful for the production of a spring excellent in fatigue characteristics in high Si steels. The steel for high-cleanliness spring with excellent fatigue characteristics according to the invention contains: in terms of mass %, C: 1.2% or less (excluding 0%); Si: 1.8% to 4%; Mn: 0.1% to 2.0%; and total Al: 0.01% or less (excluding 0%), with the remainder being iron and inevitable impurities, in which the Si amount and a solute (SIMS) Ca amount in the steel satisfy a relationship of the following expression (1):Si×10≦solute (SIMS) Ca≦Si×5×10  (1)(in which each of the solute (SIMS) Ca and Si represents the amount thereof (mass %) in the steel).