Praxair S.t. Technology, Inc.

James Kent Knapp

Thomas F Lewis, Iii

Kevin E Garing

Zhihong Tang

Thomas D Findlay

Thomas Alan Taylor

Ardy Kleyman

Tetyana P Shmyreva

Doris Kwok

Lei Liu

Albert Feuerstein

Jeffrey J McConnell

Phil O

Faraz Abbasi

Novel slurry formulations and processes for forming improved protective coatings used in the hot section components of gas turbine engines are provided. The process includes a unique two-step deposition methodology whereby the required concentration of reactive element within an improved reactive element doped aluminide coating can be consistently produced in a reproducible manner.

Slurry formulations for formation of reactive element-doped aluminide coatings and methods of forming the same

Unique and improved chromizing processes are disclosed. The processes involve forming localized chromizing coatings onto selected regions of a substrate. The chromium diffusion coatings are locally applied to selected regions of substrates in a controlled manner, in comparison to conventional chromizing processes, and further in a manner that produces less material waste and does not require diffusion-stop-off masking. Prior to or after a localized slurry chromizing process of the present invention, a layer of a platinum-group-metal (PGM) is applied to produce a PGM-modified chromium diffusion coating onto selected regions of a substrate. A second coating can be selectively applied onto other regions of the substrate.

Methods of applying chromium diffusion coatings onto selective regions of a component

Unique and improved chromium coatings derived from modified chromium-containing slurry formulations are disclosed. The slurry formulation includes a combination of a selected halide activator and buffer material that synergistically interact with each other to form chromium diffusion coatings with improved microstructure in comparison to chromium diffusion coatings produced from conventional chromizing processes. The coatings may be locally applied in a controlled manner with accuracy onto various parts, including those having internal sections with complex geometries, without masking any portion thereof.

Modified slurry compositions for forming improved chromium diffusion coatings

Unique and improved chromizing processes are disclosed. The processes involve forming localized chromizing coatings onto selected regions of a substrate. The chromium diffusion coatings are locally applied to selected regions of substrates in a controlled manner, in comparison to conventional chromizing processes, and further in a manner that produces less material waste and does not require masking. A second coating can be selectively applied onto other regions of the substrate.

This invention relates to thermally sprayed coatings having an amorphous-nanocrystalline-microcrystalline composition structure, said thermally sprayed coating comprising from about 1 to about 95 volume percent of an amorphous phase, from about 1 to about 80 volume percent of a nanocrystalline phase, and from about 1 to about 90 volume percent of a microcrystalline phase, and wherein said amorphous phase, nanocrystalline phase and microcrystalline phase comprise about 100 volume percent of said thermally sprayed coating. This invention also relates to methods for producing the coatings, thermal spray processes for producing the coatings, and articles coated with the coatings. The thermally sprayed coatings of this invention provide enhanced wear and corrosion resistance for articles used in severe environments (e.g., landing gears, airframes, ball valves, gate valves (gates and seats), pot rolls, and work rolls for paper processing).

Amorphous-nanocrystalline-microcrystalline coatings and methods of production thereof

The polishing slurry includes by weight percent, 0.1 to 50 metal oxy-acid accelerator, 0.5 to 50 cerium oxide abrasive particles and balance water. The metal oxy-acid accelerator is formed with a metal selected from the group consisting of chromium, lanthanum and rare earth metals 59 to 71, manganese, molybdenum, niobium, osmium, rhenium, ruthenium, titanium, tungsten, vanadium, yttrium and zirconium.

Polishing composition and method

A hybrid slurry mixture that polishes substrates' surfaces. The hybrid slurry includes, by weight percent, 1 to 30 primary polishing particles, 1 to 50 dispersed colloidal particles, 1 to 40 oxidizer and balance water. The primary polishing particles are metal compounds selected from the group consisting of oxides, nitrides, carbides and borides. The primary polishing particles have a particle size from about 0.1 to 2 &mgr;m mean diameter. The dispersed colloidal particles are at least one oxide selected from the group consisting of alumina and silica. The dispersed colloidal particles have a particle size from about 2 to 500 nm mean diameter.

Hybrid polishing slurry

The invention provides a mixture for polishing surfaces. The mixture includes polishing particles having an average size of less than 10 .mu.m and water. It also includes an accelerator for chemically attacking a surface and a starch for reducing vibration of polishing machines.

Polishing slurry

A thermal spray process for producing a MCrAlY-based coating wherein M is selected from the group consisting of iron, cobalt, nickel and mixtures thereof and wherein the oxygen in the fuel-oxidant mixture of the thermal spray process converts a substantial portion of the yttrium component to Y.sub.2 O.sub.3, a minor portion of the aluminum component to Al.sub.2 O.sub.3, and the Y.sub.2 O.sub.3 and Al.sub.2 O.sub.3 are present in an amount of less than 15 volume percent of the coating.

Process for producing an oxide dispersed MCrAlY-based coating

A thermal spray process for producing a MCrAlY-based coating wherein M is selected from the group consisting of iron, cobalt, nickel and mixtures thereof and wherein the carbon in the fuel of the thermal spray process converts between 30 to 80 percent by weight of the chromium component in the coating to chromium carbide.

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Pittsboro, IN, United States of America

James Kent Knapp