A system for a turbine blade tip to address wear during rubbing with a shroud, and also tip rail cooling, is provided. The turbine blade tip includes a tip rail and cooling passage(s) extending through a radially outer end surface thereof, providing direct cooling to the tip. The tip rail may include tip rail cooling inserts. The radial outer end surface of the tip rail includes a first portion radially inward of a second portion thereof. An abrasive layer extends along the first portion adjacent the cooling passage(s), and may include a matrix alloy having a plurality of cubic boron nitride (cBN) particles and a plurality of ceramic particles embedded therein. The abrasive layer extends radially outward of the second portion of the radial outer end surface. The system also may include a shroud including an abradable coating thereon.

A fluid pump is shown, comprising: a chamber comprising an inlet and an outlet, the outlet comprising a non-return valve, the chamber having a cavity comprising a cylinder; a piston slidably disposed within the cylinder; and a Tesla valve in fluid communication with the inlet, wherein the fluid pump is configured to pump fluid from the inlet to the outlet by reciprocation of the piston within the cylinder.

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.

In some examples, the disclosure describes an article and a method of making the same that includes a substrate defining an outer surface, a barrier layer on the outer surface of the substrate, the barrier layer defining a textured surface having a plurality of cells, each cell having a geometry and a depth, and an overlying layer formed on the textured surface of the barrier layer. The barrier layer may be configured to reduce migration of material from the substrate to the overlaying layer to reduce or prevent formation of cristobalite phase thermally grown oxide.

A hybrid three-layer system is presented. The hybrid three-layer system includes a two-layer composite system and an additively manufactured third layer comprising a lattice structure. The composite layer system includes a metallic substrate, a structured surface, and a thermal protection system. The structured surface may be additively manufactured onto the metallic substrate and includes structured surface features formed to project above the metallic substrate. Each of the structured surface features are separated from adjacent structured surface features by grooves. The thermal protection coating may be thermally sprayed onto the structured surface and is bonded to each of the structured surface features. The lattice structure is in contact with a surface of the metallic substrate of the composite layer system.

An article includes a ceramic-based substrate and a barrier layer on the ceramic-based substrate. The barrier layer includes a matrix phase and a network of gettering particles in the matrix phase. The gettering particles have an average maximum dimension between about 30 and 70 microns. The gettering particles have maximum dimensions that range from about 1 to 100 microns, and a dispersion of barium-magnesium alumino-silicate particles in the matrix phase. A composite material and a method of applying a barrier layer to a substrate are also disclosed.

An inner coating layer for solid-propellant rocket engines, constituted by a material comprising from 45% to 55% wt. of a a cross-linkable, unsaturated-chain polymer base, from 11% to 13% wt. of silica, from 15% to 25% wt. of vulcanizing agents and plasticizers, from 5% to 7% wt. of aramid fiber and from 10% to 15% wt. of microspheres made of a material selected among glass, quartz and nano clay, having diameter lower than 200 μm, density comprised between 0.30 and 0.34 g/cc and resistance to hydrostatic pressure greater than, or equal to, 4500 psi.

A process for coating a gas turbine engine disk comprises placing the disk having an outer surface into a chamber, the chamber configured to perform atomic layer deposition; injecting a first reactant into the chamber; forming a first monolayer gas thin film on the outer surface; removing the first reactant from the chamber; injecting a second reactant into the chamber; reacting second reactant with the first monolayer gas thin film; removing the second reactant from the chamber; and forming a protective barrier coating on the outer surface.

Airfoils for gas turbine engines are provided. In one embodiment, an airfoil formed from a ceramic matrix composite material includes opposite pressure and suction sides extending radially along a span and defining an outer surface of the airfoil. The airfoil also includes opposite leading and trailing edges extending radially along the span. The pressure and suction sides extend axially between the leading and trailing edges. The leading edge defines a forward end of the airfoil, and the trailing edge defining an aft end of the airfoil. Further, the airfoil includes a trailing edge portion defined adjacent the trailing edge at the aft end of the airfoil; a plenum defined within the airfoil forward of the trailing edge portion; and a cooling passage defined within the trailing edge portion proximate the suction side. Methods for forming airfoils for gas turbine engines also are provided.

An aircraft engine component (100) may include a wall (200) comprising an aluminum alloy and/or a magnesium alloy, and a protective coating (108) covering the wall (200). The protective coating (108) may include a prime layer (206), a silicone elastomer layer (208), and an abrasion resistant layer (210). The prime layer (206) may at least partially cover a surface (202) of the wall (200). The prime layer (206) may include a silane coupling agent and an organic titanate. The silicone elastomer layer (208) may at least partially cover the prime layer (206). The silicone elastomer layer (208) may include one or more filler materials dispersed in a matrix of cross-linked silicone polymers. The abrasion resistant layer (210) may at least partially cover the silicone elastomer layer (208). The abrasion resistant layer (210) may include a fiber-reinforced elastomeric material.