An airfoil includes an airfoil wall that defines a leading end, a trailing end, and suction and pressure sides that join the leading end and the trailing end. The airfoil wall is formed of a silicon-containing ceramic. A first environmental barrier topcoat is disposed on the suction side of the airfoil wall, and a second, different environmental barrier topcoat is disposed on the pressure side of the airfoil wall. The first topcoat is vaporization-resistant and the second topcoat is resistant to calcium-magnesium-aluminosilicate.

A preceramic resin formulation comprising a polycarbosilane preceramic polymer and an organically modified silicon dioxide preceramic polymer. A ceramic material comprising a reaction product of the polycarbosilane preceramic polymer and organically modified silicon dioxide preceramic polymer is also described. Articles comprising the ceramic material are also described, as are methods of forming the preceramic resin formulation and the ceramic material.

A component includes a substrate at least a portion of which adjacent to a surface of the substrate is made of a material including silicon; a bond coat located on the surface of the substrate and including silicon, an environmental barrier which includes an outer layer of ceramic material covering the bond coat, wherein the environmental barrier further includes a self-healing inner layer located between the bond coat and the outer layer, the inner layer including a matrix in which silico-forming particles are dispersed, these particles being capable of generating a matrix crack healing phase in the presence of oxygen.

A coated component, along with methods of its formation and use, is provided. The coated component may include a substrate having a surface, a first refractory layer on the surface of the substrate, a silicon-based bond coating on the first refractory layer, and an environmental barrier coating on the silicon-based bond coating. The silicon-based bond coating includes a silicon-phase contained within a refractory phase such that, when melted, the silicon-phase is contained within the refractory phase and between the surface of the substrate and an inner surface of the environmental barrier coating.

A composite article comprises a substrate, the substrate comprising a silicon containing material and an additive comprising boron nitride nanotubes.

A seal system includes a ceramic component, a metallic component, a silicon-containing layer, and a barrier layer. The ceramic component has a first surface region that defines a first surface roughness. The metallic component is situated adjacent to the first surface region and has a second surface region facing the first surface region. The silicon-containing layer is on the first surface region of the ceramic component and has a contact surface that defines a second surface roughness which is less than the first surface roughness. The barrier layer is on the metallic component and in contact with the silicon-containing layer and serves to limit interaction between silicon of the silicon-containing layer and the metallic component. The barrier layer includes at least one of alumina or MCrAlY.

An environmental barrier coating system for a turbine component, including an environmental barrier layer applied to a turbine component substrate containing silicon; the environmental barrier layer comprising an oxide matrix surrounding a fiber-reinforcement structure and a self-healing phase interspersed throughout the oxide matrix; wherein the fiber-reinforcement structure comprises at least one first fiber bundle oriented along a load bearing stress direction of said turbine component substrate; wherein the fiber-reinforcement structure comprises at least one second fiber bundle oriented orthogonal to the at least one first fiber bundle orientation; wherein the fiber-reinforcement structure comprises at least one third fiber woven between the at least one first fiber bundle and the at least one second fiber bundle.

A coated article, comprising an article having at least one surface having disposed thereupon an oxidation resistant coating comprising at least two constituents to form a composition, a first constituent comprising at least one thermal expansion component comprising at least about 10% by volume to up to about 99% by volume of the composition, a second constituent comprising at least one oxygen scavenger comprising at least about 1% by volume to up to about 90% by volume of the composition.

The present disclosure is directed to a method for rejuvenating a damaged coated component of a gas turbine engine. The method includes uninstalling the damaged coated component from the gas turbine engine. The method also includes isolating a first coated portion of the component of the gas turbine engine from a second coated portion of the component. In addition, the method includes simultaneously depositing a first coating material on the first coated portion of the component and a different, second coating material on the second coated portion of the component. The method also includes reinstalling the rejuvenated coated component into the gas turbine engine.

Disclosed is a thermal barrier coating system for components of a turbomachine, especially for high temperature-stressed or hot gas-stressed components of a turbomachine, comprising a ceramic coating of fully or partially stabilized zirconium oxide, and an oxide cover coating which comprises aluminum and at least one element from the group lanthanum, magnesium, silicon, calcium and sodium. The aluminum oxide exists at least partially as free α-Al.sub.2O.sub.3. Also disclosed is a method for producing a corresponding thermal barrier coating system.