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:
Apr. 04, 2017
Filed:
Mar. 13, 2013
Kobe Steel, Ltd., Kobe-shi, JP;
Kazuyuki Hamada, Kakogawa, JP;
Tatsuya Asai, Kakogawa, JP;
Kobe Steel, Ltd., Kobe-shi, JP;
Abstract
A steel sheet according to the present invention has tensile strength of 980 MPa or more, exerts a high-yield ratio, and has excellent workability (in detail, strength-ductility balance). The steel sheet contains: C: 0.06-0.12% (excluding 0.12%); Si: 0.2% or less; Mn: 2.0-3.5%; at least one element selected from the group consisting of Ti, Nb, and V of 0.01-0.15% in total; B: 0.0003-0.005%; P: 0.05% or less; S: 0.05% or less; Al: 0.005-0.1%; N: 0.015% or less; and the balance is iron and unavoidable impurities, in which the content of ferrite is more than 5% to 15% or less, that of martensite is 25-55%, and the total content of bainite and tempered martensite is 30% or more to less than 70%, based on the whole microstructure, and in which the average crystal grain size of the ferrite is 3.0 μm or less.