Abstract: Aluminum alloy compositions are disclosed, which include small amounts of calcium that result in improved surface properties of the cast aluminum. The calcium, and up to 0.25% grain refiners, are added along with alkaline earth metals, transition metals and/or rare earth metals to the aluminum alloy as a melt. The addition results in improved appearance, substantially reduced surface imperfections and reduced surface oxidation in cast ingot aluminum and aluminum alloys. The addition of small amounts of these additives, surprisingly were found to substantially eliminate vertical folds, pits and ingot cracking in more than one ingot casting technique. The additions also improved the appearance of the ingots, including reflectance. As a result, the ingots could be reduced or worked essentially right out of the casting without first conditioning the surface by, for example, scalping.

Abstract: Aluminum alloy compositions are disclosed, which include small amounts of calcium that result in improved surface properties of the cast aluminum. The calcium, and up to 0.25% grain refiners, are added along with alkaline earth metals, transition metals and/or rare earth metals to the aluminum alloy as a melt. The addition results in improved appearance, substantially reduced surface imperfections and reduced surface oxidation in cast ingot aluminum and aluminum alloys. The addition of small amounts of these additives, surprisingly were found to substantially eliminate vertical folds, pits and ingot cracking in more than one ingot casting technique. The additions also improved the appearance of the ingots, including reflectance. As a result, the ingots could be reduced or worked essentially right out of the casting without first conditioning the surface by, for example, scalping.

Abstract: Aluminum alloy compositions are disclosed, which include small amounts of calcium that result in improved surface properties of the cast aluminum. The calcium, and up to 0.25% grain refiners, are added along with alkaline earth metals, transition metals and/or rare earth metals to the aluminum alloy as a melt. The addition results in improved appearance, substantially reduced surface imperfections and reduced surface oxidation in cast ingot aluminum and aluminum alloys. The addition of small amounts of these additives, surprisingly were found to substantially eliminate vertical folds, pits and ingot cracking in more than one ingot casting technique. The additions also improved the appearance of the ingots, including reflectance. As a result, the ingots could be reduced or worked essentially right out of the casting without first conditioning the surface by, for example, scalping.

Abstract: An apparatus for improving the surface characteristics of a continuously cast metal ingot comprises: a skim dam having outer lateral edges which diverge downwardly into an upper molten surface of the ingot during casting in a mold; and means for suspending the skim dam in the upper molten surface. Preferably, the outer lateral edges intersect the upper molten surface at an angle between about 105.degree. and 150.degree., and more preferably at about a 120.degree. angle. The outer lateral edges maintain an acutely angled meniscus inwardly of the meniscus between the upper molten surface and the side surfaces of the ingot. A method for inhibiting the formation of vertical folds and oxide releases on a metal ingot continuously cast in an electromagnetic mold comprises suspending a skim dam in an upper molten surface of the ingot during casting, said skim dam having outer lateral edges which are not wetted by the upper molten surface and diverge downwardly into same.