A multilayer structure includes: a base material made of an iron-based metal material; a nitride layer that is provided on a surface of the base material through a nitriding treatment performed to the base material; an intermediate layer provided on a surface of the nitride layer; and a DLC layer provided on a surface of the intermediate layer. The intermediate layer is made of Si.sub.3N.sub.4, and the DLC layer has a thickness of 2 m to 10 m.

A turbine rotor for an aircraft engine includes a plurality of blades compressed by a compression ring made of ceramic matrix composite (CMC). The CMC includes at least one of: monofilaments and silicon carbide fibers. A method of extracting energy from an airflow using a turbine rotor of an aircraft engine is also disclosed.

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.

An article has a cavity defined by an inner surface, the cavity having a size such that a largest sphere placeable in the cavity has a diameter of less than 7 cm and a smallest sphere placeable in the cavity has a diameter of 0.5 mm; and a hard coating on the inner surface, the hard coating having a hardness between 18 to 100 GPa, the hard coating distributed on the inner surface such that a ratio of a coating thickness at a first region of the hard coating to that at a second region of the hard coating ranges from 0.75 to 1.33.

A method of treating a substrate of a turbomachine component includes applying a coating to a surface of the substrate of the turbomachine component and peening the substrate after applying the coating to the surface by directing a peening force onto the coating whereby the peening force on the coating is transferred through the coating to the substrate. A method of treating an internal surface of a turbomachine component includes directing a peening force at the internal surface within a cooling passage of the turbomachine component.

A material for water droplet erosion- and corrosion-resistant coatings, comprising metallic tungsten alloyed with carbon in a substantially uniform nano-structure that is substantially free of oxygen, other than at surface portions exposed to air or moisture. The coatings disclosed may be particularly resistant to water droplet erosion when coated onto gas or steam turbine blades.

Embodiments of the present disclosure generally relate to protective coatings on an aerospace component and methods for depositing the protective coatings. The protective coating can be anti-coking coatings to reduce or suppress coke formation when the aerospace component is heated in the presence of a fuel. In one or more embodiments, a method for depositing the protective coating on an aerospace component includes exposing the aerospace component to a cleaning process to produce a cleaned surface on the aerospace component and sequentially exposing the aerospace component to a precursor and a reactant to form a protective coating on the cleaned surface of the aerospace component by an atomic layer deposition (ALD) process. The aerospace component can be one or more of a fuel nozzle, a combustor liner, a combustor shield, a heat exchanger, a fuel line, a fuel valve, or any combination thereof.

A fuel system includes a fuel passage for conveying a hydrocarbon fuel. The hydrocarbon fuel is reactive with oxygen to form carbonaceous deposit. A device is disposed in the fuel passage such as to be exposed to the hydrocarbon fuel. The device includes first and second surfaces that are spaced from each other by a clearance gap into which the hydrocarbon fuel can infiltrate. The first and second surfaces are in sliding motion with respect to each other when the device is in operation. A frangible fluoropolymer coating is disposed on at least one of the first or second surfaces along the clearance gap. The coating is subject to the carbonaceous deposit adhering thereon. The coating is configured to allow portions to release by shearing off with the carbonaceous deposit under stress from the sliding motion to uncover a newly exposed face of the coating.

A gas turbine engine includes: a turbine section including a casing extending circumferentially about a plurality of turbine blades and having at least one seal member coated with an abradable coating. At least one turbine blade has sides and a tip and at least one seal member is located adjacent to the tip of the at least one turbine blade. The tip of the at least one turbine blade has a wear resistant layer and an abrasive coating disposed on the wear resistant layer. The wear resistant layer has a thickness less than or equal to 10 mils (254 micrometers) and includes metal boride compounds.

A gas turbine engine includes an engine static structure extending circumferentially about an engine centerline axis; a compressor section, a combustor section, and a turbine section within the engine static structure. At least one of the compressor section and the turbine section includes at least one airfoil and at least one seal member adjacent to the at least one airfoil. A tip of the at least one airfoil is metal having a wear resistant coating and the at least one seal member is coated with an abradable coating. The wear resistant coating is formed as a layer in a base metal surface of the airfoil, has a thickness less than or equal to 10 mils (254 micrometers) and includes metal boride compounds.