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:
Jul. 14, 2009
Filed:
Jun. 23, 2003
Katsumi Nakajima, Hiroshima, JP;
Takayuki Futatsuka, Hiroshima, JP;
Yasunobu Nagataki, Hiroshima, JP;
Katsumi Nakajima, Hiroshima, JP;
Takayuki Futatsuka, Hiroshima, JP;
Yasunobu Nagataki, Hiroshima, JP;
JFE Steel Corporation, Tokyo, JP;
Abstract
The invention provides a high strength cold rolled steel sheet comprising ferrite phases and second phases, in which the mean grain size of the ferrite phases is 20 μm or less, the volume fraction of the second phase is 0.1% or more to less than 10%, the absolute value |Δr| of in-plane anisotropy of r value is less than 0.15, and the thickness is 0.4 mm or more. The high strength cold rolled steel sheet of the present invention has a tensile strength of 370 to 590 MPa, and has excellent stretchability, dent resistance, surface precision, secondary working embrittlement, anti-aging, and surface appearance, therefore it is suitable for outer panels of automobile.