A blade and method for producing the blade for a gas turbine engine are described herein. The blade may include a composite airfoil. The airfoil may comprise a ceramic material, and a distal end. A tip may extend from the distal end of the airfoil. The tip of the airfoil may comprise a substantially porous structure and may comprise infiltrated material extending from an airfoil preform to a tip preform to join the airfoil preform and the tip preform.

In some examples, a method for forming an abrasive coating on a component (e.g., a turbine blade, vane, or knife ring) of a gas turbine engine. The method may include forming an abrasive coating system on a substrate, the abrasive coating system including an abrasive coating including a plurality of abrasive particles in a metal matrix; machining the abrasive coating on the substrate to define a machined abrasive coating having an abrasive coating thickness profile; and etching an outer surface of the machined abrasive coating to remove a portion of the metal matrix and form an etched metal matrix such that the abrasive particles protrude from the metal matrix.

A component for a gas turbine engine including a core and an outer enclosure. The core includes an exterior surface extending along a length between a first end and a second end and at least partially defines a cooling cavity on the exterior surface extending from the first end along at least a portion of the length. The cooling cavity is fluidly coupled to an air supply at the first end. The outer enclosure includes an outer surface. The outer enclosure is positioned outside the core and extends from the first end of the core along at least a portion of the length of the core and at least partially defines the cooling cavity.

The present invention discloses a turbine engine with at least a high pressure and a low pressure turbine section comprising a casing and at least one turbine blade rotatably mounted within the casing wherein at least part of the inner surface of the casing is covered with shrouds as abradables to provide clearance control between the inner surface and the tip of the at least one blade and wherein the tip of the blade is coated with a hard PVD coating, characterized in that the shroud material of at least the high pressure and/or the low pressure section comprises a porous ceramic based material and the hard PVD coating on the tip of the blade essentially consists of a droplet free nitride coating.

An example high-performance system may include an example high-performance component. The high-performance component may include a substrate defining a channel. The channel defines a leading ramp and a trailing ramp. The example high-performance component includes an abradable track between the leading and the trailing ramps. The abradable track includes a porous abradable composition. The example high-performance system may include a rotating component configured to contact and abrade the abradable track. An example technique for forming the abradable track includes thermal spraying a precursor composition at the channel to form the abradable track.

A method for applying an abrasive comprises: applying, to a substrate, the integral combination of: a self-braze material; and an abrasive embedded in the self-braze material; and securing the combination to the substrate.

An article includes a monolithic substrate and a coating on the monolithic substrate. The monolithic substrate is selected from graphite, silicon carbide, silicon carbide nitride, silicon nitride carbide, and silicon nitride. The coating has a free, exposed surface and includes a compound of aluminum (Al), boron (B) and nitrogen (N) in a continuous chemically bonded network having AlN bonds and BN bonds. The compound includes an atom of nitrogen covalently bonded to an atom of boron and an atom of aluminum, and the compound has a composition B.sub.xAl.sub.(1-x)N, where x is 0.001 to 0.999.

Advanced environmental barrier coating bond coat systems with higher temperature capabilities and environmental resistance are disclosed. These bond coat systems can be applied to ceramic substrates such as SiC/SiC ceramic matrix composite substrates, and can provide protection from extreme temperature, mechanical loading and environmental conditions, such as in high temperature gas turbines. Example bond coat systems can include either an advanced silicon/silicide component, an oxide/silicate component, or a combination thereof.

A rotating component includes an airfoil section with a free end, the airfoil section being formed of a composite core with a metallic skin and an abrasive coating applied to the free end.

A method for applying an abrasive comprises: applying, to a substrate, the integral combination of: a self-braze material; and an abrasive embedded in the self-braze material; and securing the combination to the substrate.