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.

Date of Patent:
Aug. 22, 2017

Filed:

Mar. 25, 2011
Applicants:

Muneaki Ikeda, Kakogawa, JP;

Yukihiro Utsumi, Kakogawa, JP;

Masaaki Miura, Kakogawa, JP;

Inventors:

Muneaki Ikeda, Kakogawa, JP;

Yukihiro Utsumi, Kakogawa, JP;

Masaaki Miura, Kakogawa, JP;

Assignee:

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

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C22C 38/02 (2006.01); C21D 9/46 (2006.01); C22C 38/00 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C21D 6/00 (2006.01); C21D 8/02 (2006.01);
U.S. Cl.
CPC ...
C22C 38/02 (2013.01); C21D 6/005 (2013.01); C21D 6/008 (2013.01); C21D 8/02 (2013.01); C21D 9/46 (2013.01); C22C 38/001 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C21D 2211/002 (2013.01); C21D 2211/005 (2013.01); C21D 2211/008 (2013.01);
Abstract

Disclosed is an ultra high strength steel plate with at least 1100 MPa of tensile strength that has both an excellent strength-stretch balance and excellent bending workability, and a method for producing the same. The metal structure of the steel plate has martensite, and the soft phases of bainitic ferrite and polygonal ferrite. The area of the aforementioned martensite constitutes 50% or more, the area of the aforementioned bainitic ferrite constitutes 15% or more, and the area of the aforementioned polygonal ferrite constitutes 5% or less (including 0%). When the circle-equivalent diameter of the aforementioned soft phases is measured, the coefficient of variation (standard deviation/mean value) is less or equal to 1.0. The ultra high strength steel plate has at least 1100 MPa of tensile strength.


Find Patent Forward Citations

Loading…