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:
Dec. 12, 2006
Filed:
Sep. 19, 2003
Nobuyuki Nakamura, Fukuyama, JP;
Takeshi Fujita, Fukuyama, JP;
Katsutoshi Ito, Fukuyama, JP;
Yasuyuki Takada, Fukuyama, JP;
Nobuyuki Nakamura, Fukuyama, JP;
Takeshi Fujita, Fukuyama, JP;
Katsutoshi Ito, Fukuyama, JP;
Yasuyuki Takada, Fukuyama, JP;
JFE Steel Corporation, Tokyo, JP;
Abstract
To provide a high carbon steel sheet having excellent hardenability and toughness, and low planar anisotropy of tensile properties affecting workability, and a method of producing the same. A high car steel sheet having chemical composition specified by JIS G 4051 (Carbon steels for machine structural use), JIS G 4401 (Carbon tool steels) or JIS G 4802 (Cold-rolled steel strips for springs), wherein more than 50 carbides having a diameter of 1.5 μm or larger exist in 2500 μm, the ratio of number of carbides having a diameter of 0.6 μm or less with respect to all the carbides is 80% or more, and the Δr is more than −0.15 to less than 0.15, herein Δr=(r0+r90−2×r45)/4, and r0, r45, and r90 shows a r-value of the directions of 0° (L), 45° (S) and 90° (C) with respect to the rolling direction respectively.