logo

For the Inventor, By the Inventor

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 9598751 B1

PDFFull Text
Date of Patent:
Mar. 21, 2017

Filed:

May. 24, 2013

High strength cold-rolled steel sheet exhibiting little variation in strength and ductility, and manufacturing method for same

Applicant:

Kobe Steel, Ltd., Kobe-shi, JP;

Inventors:

Tomokazu Masuda, Kobe, JP;

Katsura Kajihara, Kobe, JP;

Toshio Murakami, Kobe, JP;

Masaaki Miura, Kakogawa, JP;

Muneaki Ikeda, Kakogawa, JP;

Assignee:

Kobe Steel, Ltd., Kobe-shi, JP;

Attorney:

Oblon, McClelland, Maier & Neustadt, L.L.P.

Primary Examiner:

Scott Kastler

Assistant Examiner:

Vanessa Luk

Int. Cl.
CPC ...
C22C 38/00 (2006.01); C21D 9/46 (2006.01); C22C 38/38 (2006.01); C22C 38/06 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/08 (2006.01); C22C 38/12 (2006.01); C22C 38/16 (2006.01); C22C 38/18 (2006.01); C22C 38/22 (2006.01); C21D 6/00 (2006.01); C21D 8/02 (2006.01); C21D 1/26 (2006.01);
U.S. Cl.
CPC ...
C22C 38/38 (2013.01); C21D 1/26 (2013.01); C21D 6/005 (2013.01); C21D 8/0236 (2013.01); C21D 8/0263 (2013.01); C21D 9/46 (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 38/16 (2013.01); C22C 38/18 (2013.01); C22C 38/22 (2013.01);
Abstract

In a high strength cold-rolled steel plate having a specific chemical composition, a soft first phase (ferrite) has an area ratio of 20-50%, the remainder being a hard second phase (tempered martensite and/or tempered bainite), among all the ferrite grains, ferrite grains that have an average grain diameter of 10-25 μm account for a total area ratio of 80% or more, the number of the cementite grains that have an equivalent circle diameter of 0.3 μm or more is more than 0.15 piece and 1.0 piece or less per 1 μmof ferrite, and the tensile strength is 980 MPa or more.

Find Patent Forward Citations

Loading…