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:
Sep. 10, 2002
Filed:
Feb. 15, 2001
Wataru Yamada, Kimitsu, JP;
Seiki Nishida, Kimitsu, JP;
Satoshi Sugimaru, Kimitsu, JP;
Naoshi Hikita, Chiyoda-ku, JP;
Hiromi Takahashi, Kimitsu, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
The present invention provides a high carbon steel wire remarkably excellent in wire-drawability and fatigue resistance after wire drawing with a low cost due to reduced use of costly alloys. A high carbon steel wire according to the present invention is one excellent in wire-drawability and fatigue resistance after wire drawing, characterized in that; the total oxygen content is 15 to 50 ppm; among non-metallic inclusions included therein, the number of inviscid inclusions is 1.5 pieces/mm or less in average under the visual field of an optical microscope; among the inviscid inclusions, the number of those having a composition falling within composition A specified below accounts for more than 20% and the total number of those having a composition falling within composition A or B specified below accounts for 80% or more; and the thickness of the inviscid inclusions having a composition falling within composition A specified below is 40 &mgr;m or less; composition A: containing over 70% of SiO , composition B: containing 25 to 70% of SiO , 8 to 30% of MnO, 40% or less of MgO, 35% or less of Al O , 25% or less of CaO and 6% or less of TiO , and at least 5% of one or both of Al O and MgO, and additionally at least 2% of one or both of CaO and TiO .