Timothy A Kuhn

US Patent:

6733566, May 11, 2004

Filed:

Jun 9, 2003

Appl. No.:

10/457269

Inventors:

Jen C. Lin - Export PA
Timothy A. Kuhn - Frederick MD
Holger Haddenhorst - Gelsenkirchen, DE

Assignee:

Alcoa Inc. - Pittsburgh PA

International Classification:

C22B 2106

US Classification:

75709, 75604, 75684, 164 551, 164123, 420590

Abstract:

A method for preventing oxidation of molten aluminum alloy and magnesium alloy surfaces, the method comprising providing a molten aluminum alloy or magnesium alloy having a molten aluminum or magnesium alloy surface; covering the molten aluminum or magnesium alloy surface with an initial layer of petroleum coke, the initial layer of petroleum coke having an initial layer thickness of about 0. 75 inches; oxidizing a portion of the initial layer of petroleum coke to form a working layer of petroleum coke covering the molten metal surface, the working layer of coke having a working layer thickness of about 0. 5 inches, and a layer of carbon dioxide immediately adjacent to and contiguous with the working layer of petroleum coke; and adding additional petroleum coke to the working layer of petroleum coke to maintain the working layer thickness at about 0. 5 inches.