Reynolds Metals Company

Gary B Parker

Douglas V Stewart

James R Guttery

A method for improving the surface quality of electromagnetically cast aluminum alloy ingot includes the addition of an effective amount of calcium prior to the ingot head of an ingot mold of an electromagnetic casting station. The addition of calcium is regulated such that the aluminum alloy cast ingot contains a maximum of 0.05 weight percent calcium. Addition of the calcium prior to the ingot head produces a cast ingot which is generally free of surface imperfections on side surfaces thereof so that the cast ingot can be directly worked or rolled to a desired gauge without a scalping or surface conditioning treatment. The calcium can be added during melting, alloying, filtering, degassing or transferring of the molten aluminum prior to casting. An electromagnetically cast aluminum alloy ingot is produced, preferably an AA5182 can end stock alloy, which is essentially free of surface imperfections to permit direct rolling or other working of the cast ingot without a surface conditioning treatment.

Method for improving surface quality of electromagnetically cast

A porous plug assembly for use in a vessel containing molten metal, such as a melting furnace or a holding furnace, for introducing fluxing or other gases into the molten metal. The porous plug assembly includes a frustoconical porous refractory core member that is enclosed around its side and bottom by a non-porous refractory lining. Positioned about the outer surface of the non-porous refractory lining is a metallic outer liner, preferably made from inconel, which includes a ceramic anti-corrosion coating. A gas distribution pipe, which also can be made from inconel, extends upwardly through the bottom of the metallic outer liner, through the non-porous refractory lining, and into the interior of the core member for introducing a fluxing gas therein. Surrounding the intermediate, non-porous refractory lining and the metallic outer liner is a refractory nest block. The fluxing gas passes through the porous core member and exits at the top thereof to enter the molten metal melt. A plurality of such porous plugs are distributed over the bottom wall of a melting or a holding furnace for improved distribution of the fluxing gas throughout the melt.

Growing community of inventors

Moulton, AL, United States of America

Gary B Parker