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:
Mar. 28, 2006
Filed:
Sep. 27, 2001
Yar-ming Wang, Troy, MI (US);
Hong-hsiang Kuo, Troy, MI (US);
Sheila Farrokhalaee Kia, Bloomfield Hills, MI (US);
Yar-Ming Wang, Troy, MI (US);
Hong-Hsiang Kuo, Troy, MI (US);
Sheila Farrokhalaee Kia, Bloomfield Hills, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A method is disclosed for forming a clear anodized coating on an aluminum base alloy containing more than three percent by weight magnesium. The alloy surface to be anodized is treated with an aqueous solution of a mineral acid such as sulfuric acid (10 to 20%), nitric acid (10 to 30%) or phosphoric acid (40 to 80%) under the influence of a relatively low voltage direct current. This treatment suitably reduces the magnesium content of the surface layer and, subsequently, a relatively low current density anodization in sulfuric acid produces the clear coating. The clear coating may then be colored by known processes.