Alcoa Inc.

Alcon, Inc.

Ray T Richter

David H DeYoung

Patricia Stewart

James R Anglin

James L Kirby

Brian C Reynolds

David R Gildemeister

Charles W Shanko

William F McGinnis

Jeffrey J Wiesner

Larry F Wieserman

Thomas J Kasun

Mark D Crowley

Jim N Hart

Lawrence E Klosterman

Andrzej Maslanka

Jim M Hart

Larry F Weiserman

Dean K Vinnedge

David H Deyoung

William F Mcginnis

An apparatus for direct chill casting of metal having an open ended mold cavity formed by a casting surface, a refractory sleeve adapted to receive molten metal, a coolant delivery system for supplying coolant to chill the descending hot metal body, and a boron nitride ring mounted between the refractory sleeve and the peripheral wall of the mold cavity. A downspout may be used instead of a refractory sleeve having a flow control rod or floating baffle to control the amount of molten metal entering the mold cavity. A process for direct chill casting of a metal including continuously filling the cavity with molten metal and permitting the metal to move downwardly through the mold to form an ingot, and simultaneously chilling the ingot by spraying coolant on the ingot from the coolant delivery system.

Process and apparatus for direct chill casting

In one embodiment, an apparatus for direct chill casting of metal includes an open ended mold cavity formed by a casting surface with an upper end and a lower end, a refractory sleeve located at the upper end of the mold cavity being adapted to receive molten metal, a coolant delivery system below the lower end of the mold for supplying coolant to chill the descending hot metal body, and a boron nitride ring mounted between the refractory sleeve and the peripheral wall of the mold cavity. Another embodiment further includes a downspout instead of a refractory sleeve that is located at the upper end of the mold cavity being adapted to receive molten metal having a flow control rod or a floating baffle where the flow control rod controls the amount of molten metal to enter the mold cavity.

In a lubricant composition suitable for use in the manufacture of aluminum alloys comprising lubricant base selected from the group consisting of solid lubricants, liquid lubricants, grease lubricants, emulsion lubricants, and dispersion lubricants, the improvement wherein the lubricant composition further comprises: an effective amount of water and surfactant. It is believed that mixing oil with water and surfactant provides a method for uniformly distributing the surface oxide at the meniscus for casting applications. Uniform distribution of the oxide at the meniscus reduces vertical fold formation that can lead to cracks in the aluminum ingot. In addition, the mixture promotes uniform heat transfer around the mold. Uniform heat transfer around the mold allows the solidifying aluminum alloy to stay in contact with the mold longer and form stronger ingot shells. A process for continuous or semi-continuous casting of aluminum alloys via the use of this lubricant composition is also disclosed.

Lubricant for improved surface quality of cast aluminum and method

In a lubricant composition suitable for use in the manufacture of aluminum alloys comprising a lubricant base, the improvement wherein the lubricant composition further comprises: an effective amount of water, surfactant, and a high viscosity organic material having a low vapor pressure. It is believed that this mixture provides a method for uniformly distributing the surface oxide at the meniscus for casting applications and increasing meniscus stability. Uniform distribution of the oxide and increased stability at the meniscus reduces vertical fold formation that can lead to cracks in the aluminum ingot. In addition, the mixture promotes uniform heat transfer around the mold. Uniform heat transfer around the mold allows the solidifying aluminum alloy to stay in contact with the mold longer and form stronger ingot shells. A process for continuous or semi-continuous casting of aluminum alloys via the use of this lubricant composition is also disclosed.

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. Also disclosed is a method of improving the surface properties and preventing surface imperfections and cracking of cast aluminum alloys. The method includes the steps of adding calcium to a molten aluminum alloy that is essentially free of Be and casting the aluminum alloy using any commonly used technique.

Aluminum alloys having improved cast surface quality

A method and apparatus for reducing crop losses during slab and ingot rolling concerns the formation of a slab ingot having a specially configured or shaped butt end and optionally a head end as well. A special shape is formed by machining, forging or preferably by casting. The special shape at the butt end is imparted during casting by a specially shaped bottom block or starter block. The special shape of the bottom block is imparted to the cast ingot butt end. The specially shaped butt end of a slab shaped ingot is generally rectangular in shape and has longitudinally outwardly extending, enlarged portions, which slope downwardly toward a depressed central valley region. The lateral sides of the enlarged end portions and the depressed valley region carry transversely extending, tapered or curved edges. A similar shape may be imparted to the head end of the ingot at the conclusion of a casting run through the use of a specially shaped hot top mold or by way of machining or forging the cast head end. During subsequent hot rolling in a reversing roughing mill, the specially shaped slab ingot minimizes the formation of overlap and tongue so as to improve material recovery by reducing end crop losses and to increase rolling mill efficiency by increasing metal throughput in the mill.

Method for reducing crop losses during ingot rolling

Growing community of inventors

Murrysville, PA, United States of America

Ray T Richter