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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.:

US 10435762 B1

PDFFull Text
Date of Patent:
Oct. 08, 2019

Filed:

Mar. 13, 2015

High-yield-ratio high-strength cold-rolled steel sheet and method of producing the same

Applicant:

Jfe Steel Corporation, Tokyo, JP;

Inventors:

Katsutoshi Takashima, Chiba, JP;

Yoshihiko Ono, Fukuyama, JP;

Kohei Hasegawa, Tokyo, JP;

Assignee:

JFE Steel Corporation, Tokyo, JP;

Attorney:

DLA Piper LLP (US)

Primary Examiner:

Helene Klemanski

Int. Cl.
CPC ...
C21D 9/46 (2006.01); C21D 8/02 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/08 (2006.01); C22C 38/12 (2006.01); C22C 38/14 (2006.01); C22C 38/16 (2006.01); C22C 38/18 (2006.01); C22C 38/28 (2006.01); C22C 38/32 (2006.01); C22C 38/38 (2006.01); C22C 38/00 (2006.01);
U.S. Cl.
CPC ...
C21D 9/46 (2013.01); C21D 8/0226 (2013.01); C21D 8/0236 (2013.01); C21D 8/0263 (2013.01); C21D 8/0278 (2013.01); C22C 38/00 (2013.01); C22C 38/001 (2013.01); C22C 38/002 (2013.01); C22C 38/005 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/08 (2013.01); C22C 38/12 (2013.01); C22C 38/14 (2013.01); C22C 38/16 (2013.01); C22C 38/18 (2013.01); C22C 38/28 (2013.01); C22C 38/32 (2013.01); C22C 38/38 (2013.01); C21D 8/0273 (2013.01); C21D 2211/001 (2013.01); C21D 2211/002 (2013.01); C21D 2211/005 (2013.01); C21D 2211/008 (2013.01);
Abstract

A high-strength cold-rolled steel sheet has a composite structure containing 0.15 to 0.25% by mass of C, 1.8 to 3.0% by mass of Mn, and 0.0003 to 0.0050% by mass of B, and having a ferrite volume fraction of 20% to 50%, a retained austenite volume fraction of 7% to 20%, a martensite volume fraction of 1% to 8%, and the balance containing bainite and tempered martensite, and in the composite structure, ferrite has an average crystal grain diameter of 5 μm or less, retained austenite has an average crystal grain diameter of 0.3 to 2.0 μm and an aspect ratio of 4 or more, martensite has an average crystal grain diameter of 2 μm or less, a metal phase containing both bainite and tempered martensite has an average crystal grain diameter of 7 μm or less, the ratio of the volume fraction of tempered martensite to the volume fraction of a metal structure other than ferrite is 0.60 to 0.85, and the average C concentration in retained austenite is 0.65% by mass or more.

Find Patent Forward Citations

Takashima, Katsutoshi. (2019). High-yield-ratio high-strength cold-rolled steel sheet and method of producing the same (U.S. Patent No. 10435762). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/10435762

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

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