United Technologies Corporation

Joshua E Persky

Joseph Parkos, Jr

Gary M Lomasney

James Thompson Beals

David A Litton

Carl R Verner

Stephen Douglas Murray

Jacob A Snyder

Steven J Bullied

Dilip M Shah

Daniel A Bales

Dinesh K Gupta

Keith A Santeler

David N Long

Sudhangshu Bose

Daniel F Paulonis

John J Marcin

Edward R Szela

Nicholas J Piela

Glenn A Cotnoir

John D Wiedemer

Lea D Kennard

Dawn D Mandich

David A Lambert

Venkat Seetharaman

David L Lambert

Forrest Harrington

Paul W Kimball

John R Plourde

Dat Van Nguyen

Stephen D Murray

Nathan Palumbo

Keith Santeler

A workpiece, such as a turbine engine component, comprises a substrate, a thermal barrier coating on the substrate, and a hard erosion barrier deposited over the thermal barrier coating. The erosion barrier preferably has a Vickers hardness in the range of from 1300 to 2750 kg/mm. The erosion barrier may be formed from aluminum oxide, silicon carbide, silicon nitride, or molybdenum disilicide. The erosion barrier may be formed using either an electrophoretic deposition process or a slurry process.

Erosion barrier for thermal barrier coatings

A substrate is coated by applying an essentially pure aluminum first layer to a surface of the substrate. At least a first portion of the first layer is oxidized so as to provide a protective coating of desired properties. The substrate may be a refractory metal-based investment casting core.

Non-oxidizable coating

A core for investment casting processes includes a core having one or more ceramic materials; and an exterior layer of metal material not susceptible to oxidation under investment casting operating conditions. A method for casting a turbine engine component having an internal passageway includes the steps of forming one or more mold sections each having internal surfaces and at least one of the aforementioned cores for forming one or more turbine engine components having at least one internal passageway; assembling the one or more mold sections; introducing a molten alloy into the one or more assembled mold sections; and consuming the metal of the at least one core during the process.

Metallic coated cores to facilitate thin wall casting

A substrate is coated by applying a first layer atop the substrate and including, in major weight part, a non-refractory first metal. A second layer is applied atop the first layer and includes, in major weight part, a carbide and/or nitride of a second metal. A third layer is applied atop the second layer and comprises, in major weight part, a ceramic. The substrate may be a refractory metal-based investment casting core.

A refractory metal core for use in a casting system has a coating for providing oxidation resistance during shell fire and protection against reaction/dissolution during casting. In a first embodiment, the coating includes at least one oxide and a silicon containing material. In a second embodiment, the coating includes an oxide selected from the group of calcia, magnesia, alumina, zirconia, chromia, yttria, silica, hafnia, and mixtures thereof. In a third embodiment, the coating includes a nitride selected from the group of silicon nitride, sialon, titanium nitride, and mixtures thereof. Other coating embodiments are described in the disclosure.

Refractory metal core coatings

A substrate is coated by applying a first layer atop the substrate and comprising, in major weight part, a non-refractory first metal. A second layer is applied atop the first layer and comprises, in major weight part, a carbide and/or nitride of a second metal. A third layer is applied atop the second layer and comprises, in major weight part, a ceramic. The substrate may be a refractory metal-based investment casting core.

An at least two step heating process is used to strengthen the shell of an investment casting mold including a refractory metal core. The first stage may occur under otherwise oxidizing conditions at a low enough temperature to avoid substantial core oxidation. The second stage may occur under essentially non-oxidizing conditions at a higher temperature.

Methods for manufacturing investment casting shells

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Carbondale, CO, United States of America

Joshua E Persky