Articles, such as components for high temperature turbomachinery components, include one or more coatings bearing certain perovskite compositions resistant to incursion by liquid calcium-magnesium-aluminum-silicon-oxide (CMAS) materials during service. The CMAS-reactive material includes a perovskite-structured oxide, which comprises a) a rare earth element, b) niobium, tantalum or a combination of tantalum and niobium, and c) oxygen. The CMAS-reactive material is present in an effective amount to react with a CMAS composition at an operating temperature, thereby forming a reaction product having one or both of melting temperature and viscosity greater than that of the CMAS composition.

An article including a substrate and a plurality of coatings disposed on the substrate is presented. The plurality of coatings includes a thermal barrier coating disposed on the substrate; and a protective coating including a calcium-magnesium-aluminum-silicon-oxide (CMAS)-reactive material disposed on the thermal barrier coating. The CMAS-reactive material has an orthorhombic weberite crystal structure. The CMAS-reactive material is present in the plurality of coatings in an effective amount to react with a CMAS composition at an operating temperature of the thermal barrier coating, thereby forming a reaction product having one or both of melting temperature and viscosity greater than that of the CMAS composition. A method of making the article and a related turbine engine component are also presented.

A seal assembly is disclosed for sealing a high pressure fluid cavity from a low pressure fluid cavity. The cavities are at least partially disposed between a rotatable shaft and a sump housing. The seal assembly comprises a circumferential runner and a seal ring. The circumferential runner is carried by the shaft and has a radially outward facing seal surface extending axially along the shaft. The seal ring is sealing engaged with the sump housing and has a radially inward facing seal surface that sealingly engages the radially outward facing seal surface of the runner. The runner and the seal ring are formed from materials having coefficients of thermal expansion that are matched to effect sealing engagement between the runner and the seal ring over a predetermined range of operating temperatures.

A piston seal assembly for a gas turbine engine includes a seal composed of a nickel-based superalloy; a component in contact with the seal and defining a seal-counterface; and a coating on the seal at the seal-counterface, wherein the coating is a metal alloy binder phase and a hard particle phase distributed through the binder phase.

A turbine apparatus is disclosed including a first article and a second article disposed between the first article and a hot gas path of a turbine. The first article includes at least one first article cooling channel in fluid communication with and downstream from a cooling fluid source, and the second article includes at least one second article cooling channel in fluid communication with and downstream from the at least one first article cooling channel. A method for redundant cooling of the turbine apparatus is disclosed including flowing a cooling fluid from the cooling fluid source through at least one first article cooling channel, exhausting the cooling fluid from the at least one first article cooling channel into at least one second article cooling channel, and flowing the cooling fluid through the at least one second article cooling channel.

A method for forming a coating on a surface of an airfoil is provided, where the airfoil has a leading edge, a trailing edge, a pressure side, and a suction side. The method can include forming a platinum-group metal layer on the surface of the airfoil along at least a portion of the trailing edge, and forming an aluminide coating over the surface of the airfoil of the leading edge, the trailing edge, the pressure side, and the suction side. The leading edge may be substantially free from any platinum-group metal. The method may further include, prior to forming the aluminide coating, forming a bond coating on the surface of the airfoil along the leading edge, and after forming the aluminide coating, forming a thermal barrier coating over the bond coating. A method is also generally provided for repairing a coating on a surface of an airfoil.

A ceramic matrix composite article, method for forming the article, and perforated ply which may be incorporated therein are disclosed. The article includes at least one shell ply forming an exterior wall having first and second portions and defining a plenum. An annular brace formed of at least one structural support ply is disposed within the plenum, including a first integral portion integral with and part of the first portion of the exterior wall, a first curved portion extending from the first integral portion and curving across the article plenum to the second portion of the exterior wall, a second integral portion integral with and part of the second portion of the exterior wall, a second curved portion extending from the second integral portion and curving across the article plenum to the first curved portion, and an overlap in which the first and second curved portions are integral.

A sliding component having a wear-resistant coating includes a sliding component formed of a Ni alloy, and a wear-resistant coating provided on a sliding surface of the sliding component. The wear-resistant coating has, at least on the surface side thereof, an Al-containing Co alloy layer which contains Co as a main component, at least one of W, Ni, Mo, Fe, Si, and C, Cr, and 0.3% by mass or more and 26% by mass or less of Al.

A method comprises discharging from a metal vaporization device a vapor of a metal or a metal precursor to a chemical vapor infiltration device where the chemical vapor infiltration device is in fluid communication with the metal vaporization device. The chemical vapor infiltration device contains a preform containing ceramic fibers. The preform is infiltrated with a metallic coating or a coating of a metallic precursor along with a ceramic precursor coating. The metallic coating and/or the metallic precursor coating and the ceramic precursor coating are applied sequentially or simultaneously.

High temperature stable thermal barrier coatings useful for substrates that form component parts of engines such as a component from a gas turbine engine exposed to high temperatures are provided. The thermal barrier coatings include a multiphase composite and/or a multilayer coating comprised of two or more phases with at least one phase providing a low thermal conductivity and at least one phase providing mechanical and erosion durability. Such low thermal conductivity phase can include a rare earth zirconate and such mechanical durability phase can include a rare earth a rare earth aluminate. The different phases are thermochemically compatible even at high temperatures above about 1200° C.