Abstract: A process for applying an oxidation resistant coating to an article includes the steps of mixing at least about 10% by volume to up to about 99% by volume of a slurry at least one silica based material having a viscosity of about 1×102 poise to about 1×107 poise at a temperature of about 1,292° F. (700° C.) to about 3,272° F. (1,800° C.) at least about 1% by volume to up to about 90% by volume of the slurry at least one oxygen scavenger, and a liquid medium to form the slurry; coating an article with the slurry to form a slurry coated article; and heat treating under an inert atmosphere the slurry coated article to form an article having at least one oxidation resistant coating layer containing the at least one oxygen scavenger.

Abstract: Coatings containing at least 85% by volume crystalline mullite with less than 15% by volume of amorphous material and mullite dissociation phases are plasma sprayed onto the surface of a silicon based ceramic substrate by closely controlling the plasma spray parameters including the mullite feed stock and its particle size, the nozzle outlet stand-off distance, movement of the substrate past the plasma flow, back side heating of the substrate and the powder feed rate through the plasma spray gun.

Abstract: The present invention is a nanocomposite layer applied to the leading edge of an airfoil. The nanocomposite is an elastomeric matrix reinforced with nanosized reinforcing particles ranging in size from about 0.5 to 1000 nanometers and preferably ranging in size from about 5 to 100 nanometers. These nanosized reinforcing particles improve the mechanical properties of a pure elastomer. Improving such properties assists the nanocomposite layer in absorbing and dissipating the impact energy caused by the repeated impact of particulate matter, such as sand and rain. Adding the nanosized reinforcing particles to an elastomer allows the nanocomposite to absorb the impact energy over a larger volume in comparison to a pure elastomeric material. The nanocomposite layer is, therefore, capable of withstanding the repeated impact caused by the particulate matter for a greater length of time compared to a pure elastomer.

Abstract: Coatings containing at least 85% by volume crystalline mullite with less than 15% by volume of amorphous material and mullite dissociation phases are plasma sprayed onto the surface of a silicon based ceramic substrate by closely controlling the plasma spray parameters including the mullite feed stock and its particle size, the nozzle outlet stand-off distance, movement of the substrate past the plasma flow, back side heating of the substrate and the powder feed rate through the plasma spray gun.

Abstract: A ceramic coating for a metal article includes a metallic bond coat deposited on the metal article, at least one MCrAlY/ceramic layer deposited on the bond coat, and a ceramic composite top layer deposited on the MCrAlY/ceramic layer. The M in MCrAlY stands for Fe, Ni, Co, or a mixture of Ni and Co. The ceramic in the MCrAlY/ceramic layer comprises mullite, alumina, zircon, sillimanite, sodium zirconium phosphate, fused silica, cordierite, aluminum titanate, or zirconia. The ceramic composite top layer comprises a ceramic matrix and at least one secondary phase. A method of making the coating includes sequentially depositing a metallic bond coat on the metal article, at least one MCrAlY/ceramic layer on the bond coat, and a ceramic composite top layer on the MCrAlY/ceramic layer.

Abstract: This invention relates to abrasive layers for use in the gas turbine industry. The preferred embodiment of the invention comprises nickel coated, yttria doped silicon nitride particulates dispersed within a nickel base superalloy matrix which is substantially free of oxides. The layer is formed using low pressure plasma spray processes.