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:
Dec. 09, 2014
Filed:
Sep. 20, 2012
Jfe Steel Corporation, Tokyo, JP;
JFE Steel Corporation, , JP;
Abstract
A galvannealed steel sheet having high corrosion resistance after painting includes, on a mass percent basis, C: 0.05% to 0.15%, Si: 0.1% to 1.0%, Mn: 0.5% to 2.7%, Al: ≦1.00%, P: ≦0.025%, S: ≦0.025%, and Cr: 0% to 0.8% as chemical components, the remainder being Fe and incidental impurities. The galvannealed steel sheet includes a galvannealed layer in an amount of 20 to 120 g/mper side, a percentage of exposed zinc metal of the galvannealed layer surface being 20% or more and less than 80%, and an amount of internal oxidation in a region disposed not more than 5 μm from the surface of the steel sheet is 0.02 g/mor more and 0.1 g/mor less: Si≦0.68%, Cr≦−1.25Si+0.85, and Si>0.68%, Cr=0, wherein Si and Cr denote respective contents (mass %) of Si and Cr.