Other

Electric Power Research Institute Incorporated

Wisconsin Alumni Research Foundation

Inco Limited

Wisconsin Electric Power Company

Oshkosh Truck Corporation

Intelligent Composites, LLC

Pradeep K Rohatgi

Bruce W Ramme

Thomas Francis Stephenson

John J Noegel

James A Bell

David J Weiss

Robert M Hathaway

Anthony Edward Moline Warner

James H Hunter, Iii

Christopher T Jordan

Benjamin F Schultz

James Alexander Evert Bell

Simon S Beno

The present invention provides an aluminum hybrid metal matrix composite including cerium and graphite. The aluminum-cerium intermetallic is stable at temperatures up to a melting point of aluminum and graphite provides in situ lubrication. This stability is advantageous in applications such as cylinder liners and other applications where strength and stiffness at elevated temperatures are required.

Aluminum based alloy containing cerium and graphite

The invention discloses the internal structures and processes to synthesize the structure of self-healing materials, especially metallic materials, metal matrix micro and nanocomposites. Self-healing is imparted by incorporation of macro, micro or nanosize hollow reinforcements including nanotubes, filled with low melting healing material or incorporation of healing material in pockets within the metallic matrix; the healing material melts and fills the crack. In another concept, macro, micro and nanosize solid reinforcements including ceramic and metallic particles, and shape memory alloys are incorporated into alloy matrices, specially nanostructured alloy matrices, to impart self healing by applying compressive stresses on the crack or diffusing material into voids to fill them. The processes to synthesize these self-healing and nanocomposite structures, including pressure or pressureless infiltration, stir mixing and squeeze casting in addition to solid and vapour phase consolidation processes are part of this invention.

Self healing lead, tin, and their alloys, and solders, incorporating shape memory alloys, reactive particles and hollow vascular networks

The invention discloses the internal structures and processes to synthesize the structure of self-healing materials, especially metallic materials, metal matrix micro and nanocomposites. Self-healing is imparted by incorporation of macro, micro or nanosize hollow reinforcements including nanotubes, filled with low melting healing material or incorporation of healing material in pockets within the metallic matrix; the healing material melts and fills the crack. In another concept, macro, micro and nanosize solid reinforcements including ceramic and metallic particles, and shape memory alloys are incorporated into alloy matrices, specially nanostructured alloy matrices, to impart self healing by applying compressive stresses on the crack or diffusing material into voids to fill them. The processes to synthesize these self-healing and nanocomposite structures, including pressure or pressureless infiltration, stir mixing and squeeze casting in addition to solid and vapor phase consolidation processes are part of this invention.

Self-healing aluminum alloys incorporating shape metal alloys and reactive particles

The invention discloses the internal structures and processes to synthesize the structure of self-healing materials, specially metallic materials, metal matrix micro and nanocomposites. Self healing is imparted by incorporation of macro, micro or nanosize hollow reinforcements including nanotubes, filled with low melting healing material or incorporation of healing material in pockets within the metallic matrix; the healing material melts and fills the crack. In another concept, macro, micro and nanosize solid reinforcements including ceramic and metallic particles, and shape memory alloys are incorporated into alloy matrices, specially nanostructured alloy matrices, to impart self healing by applying compressive stresses on the crack or diffusing material into voids to fill them. The processes to synthesize these self healing internal structures including pressure or pressureless infiltration, stir mixing and squeeze casting in addition to solid and vapor phase consolidation processes are part of this invention.

Self healing metals and alloys&#x2014;including structural alloys and self-healing solders

Methods for increasing the amount of cenospheres in a fly ash sample are disclosed. The cenospheres are obtained in a dry state by using air as the 'fluid' media for separation. In one version, the invention is a two step process, that is, screen by size followed by density separation such as in a fluidizing vertical column by density. In another version of the invention, the separation by density is followed by screening by size. Additional cycles can improve purity as defined by concentration of cenospheres.

Separation of cenospheres from fly ash

This composite consists of an aluminum-alloy matrix containing by volume percent, 0.4 to 8.8 alumina, 1 to 4.4 carbon or graphite and 0.5 to 20 nickel-bearing aluminide. The alumina particles have an average size between 3 and 250 &mgr;m and the carbon and graphite particles have an average size between 10 and 250 &mgr;m. The composite is cast by stirring alumina and carbon or graphite contained in a molten aluminum or aluminum-base alloy to form a molten mixture. The molten mixture is cast directly from a temperature above the liquidus of the matrix alloy. While solidifying, carbon or graphite particles delay or hinder the settling of alumina to create a more uniform composite structure. The resulting composite structure contains an aluminum-base alloy, alumina, carbon or graphite and nickel-bearing aluminide dispersoids.

Cast-alumina metal matrix composites

Metal matrix composites are made by infiltrating packed loose fly ash with molten metal or metal alloy under low pressure. In some embodiments the infiltration is driven by pressurized gas. Coating the fly ash prior to infiltration can lower the threshold of pressure required for satisfactory infiltration by the molten metal. In some embodiments nickel coated cenosphere fly ash is employed. Resulting metal-fly ash composites have high volume fractions of fly ash, and the fly ash is uniformely distributed in the metal matrix. The densities of the composites are relatively low, particularly in composites made using cenosphere fly ash.

Metal-fly ash composites and low pressure infiltration methods for

Metal matrix composites comprising of a solid preform comprising of a filler phase containing fly ash and a binding material having a binder to water ratio of 1:1 to 1:9, wherein the preform contains a metal homogeneously distributed within the preform.

Metal matrix composite including homogeneously distributed fly ash,

Inserts of powder compacts or metal matrix composite inserts in the form of rods, bars, plates, wires, wire mesh, ribbons, chaplets, mold coatings or machining chips are placed in the sprue, sprue basin, runner, or a mold in gate of a static sand mold. The molten metal stream partly or completely melts the inserts releasing the reinforcements which get mixed with the molten alloy streams to form the shaped casting of the composite.

Nonferrous cast metal matrix composites

A iron-based material such as cast iron is made by a process wherein filler particles are added to an iron base metal, as the base metal is poured into the mold. Pieces containing ceramic filler particles held together by a binder can be disposed in the mold prior to pouring molten iron base metal therein. Molten iron base metal is then poured into the mold so that the molten base metal contacts the pieces, gradually dissolving the filler. The filler becomes distributed throughout the molten base metal within the mold. Upon cooling, the base metal has the filler distributed therein, resulting in a iron-based material. The resulting material is particularly useful for making vehicle parts normally made of cast iron or steel.

Process for casting a light-weight iron-based material

A reinforcing phase comprising fly ash is combined with an aqueous medium comprising a binder to produce a slurry. The slurry is then dried to produce a preform of the reinforcing phase. Molten metal is then introduced into the preform, resulting in a metal matrix composites. The reinforcing phase of the subject composites may be present in excess of 50%.

Method of producing metal matrix composites containing fly ash

The invention provides an aluminum-base composite material. The aluminum-base material contains a uniform distribution of carbide particles and lubricating phase particles such as carbon or graphite. The carbide particles increase hardness for improved wear resistance. The lubricating phase particles provide improved wear resistance and especially improve unlubricated wear resistance under increased loads. Finally, a dispersoid of nickel aluminide intermetallic phase may also be used to provide additional hardness and wear resistance. The composite is formed by introducing carbide particles and lubricating phase such as graphite into a molten aluminum alloy to neutraliize buoyancy and to form an aluminum-base mixture. Mixing the aluminum-base mixture to uniformly distribute carbide and carbon particles throughout the molten aluminum. Carbide and carbon particles counteract each other to remain uniformly distributed throughout the aluminum-base alloy despite prolonged holding or cooling times.

Method of making an aluminum-base metal matrix composite

A metal matrix composite consisting of aluminum silicon alloy reinforced with graphite fibers exhibits improved mechanical and physical properties when the graphite fibers are subjected to external cooling.

Thermal management of fibers and particles in composites

A method of casting metal matrix composites wherein there is a wide disparity in the respective densities of the metal matrix and the reinforcing particles. The particles are added to a melt of molten metal and the mixture is stirred using an impeller rotating at a high speed so as to ensure an even distribution of the less dense reinforcing particles throughout the denser metal matrix.

Growing community of inventors

Milwaukee, WI, United States of America

Pradeep K Rohatgi