A component for a gas turbine engine includes an airfoil section including a free end and an abrasive coating sprayed onto the free end, the abrasive coating including a polymer matrix and an abrasive filler, the abrasive filler between about 50%-75% by volume of the abrasive coating.

An abrasive coating system for a substrate of an airfoil in a turbine engine high pressure compressor, comprising a plurality of grit particles adapted to be placed on a top surface of the substrate; a matrix material bonded to the top surface; the matrix material partially surrounds the grit particles, the matrix material consisting of unalloyed chromium and unalloyed aluminum distributed throughout the matrix material, wherein the grit particles extend above the matrix material relative to the top surface; and a film of oxidant resistant coating applied over the plurality of grit particles and the matrix material.

A gas turbine engine according to an example of the present disclosure includes, among other things, a propulsor including a circumferential array of blades, a low pressure compressor section including a low pressure compressor section inlet with a low pressure compressor section inlet annulus area and a low pressure turbine section. The low pressure turbine section includes a maximum gas path radius, the blades include a maximum radius, and a ratio of the maximum gas path radius to the maximum radius of the blades is equal to or greater than 0.35, and is less than 0.55.

A gas turbine engine includes a blade outer air seal, a ceramic vane, and a cooling passage circuit that extends through a first internal passage in the blade outer air seal and a second internal passage in the ceramic vane.

A system may include a powder source; a powder delivery device; an energy delivery device; and a computing device. The computing device may be configured to: control the powder source to deliver metal powder to the powder delivery device; control the powder delivery device to deliver the metal powder to a surface of an abrasive coating; and control the energy delivery device to deliver energy to at least one of the abrasive coating or the metal powder to cause the metal powder to be joined to the abrasive coating.

A turbofan engine according to an example of the present disclosure includes, among other things, a fan including an array of fan blades rotatable about an engine axis, a compressor including a high pressure compressor section and a low pressure compressor section, the low pressure compressor section including a low pressure compressor section inlet with a low pressure compressor inlet annulus area, a fan duct including a fan duct annulus area outboard of the low pressure compressor section inlet, and a turbine having a high pressure turbine section and a low pressure turbine section driving the fan through a speed reduction mechanism, wherein the low pressure turbine section defines a maximum gas path radius and the fan blades define a maximum radius, and a ratio of the maximum gas path radius to the maximum radius of the fan blades is less than 0.6.

The invention relates to an abradable coating for a turbomachine, comprising a mineral compound having a Mohs hardness of 6 or less and a melting temperature of more than 450° C. or even 800° C., and a polymeric compound with a content of between 40% and 70% by volume.

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 coating method includes depositing a slurry including a coarsely particulate ceramic and a finely particulate ceramic on a base material configured with an oxide-based ceramics matrix composite such that a proportion of coarse particles decreases towards a surface of the base material; forming a bond coating by performing a heat treatment on the base material on which the slurry has been deposited; and forming a top coating by thermally spraying a ceramic onto the bond coating. The oxide-based ceramics matrix composite is an alumina silica type oxide-based ceramics matrix composite. The coarsely particulate ceramic and the finely particulate ceramic are alumina-based powder.

A turbofan engine according to an example of the present disclosure includes, among other things, a fan including a circumferential array of fan blades, a compressor in fluid communication with the fan, the compressor including a low pressure compressor section and a high pressure compressor section, the low pressure compressor section including a low pressure compressor section inlet with a low pressure compressor section inlet annulus area, a fan duct including a fan duct annulus area outboard of the a low pressure compressor section inlet, a turbine in fluid communication with the combustor, the turbine having a high pressure turbine section and a low pressure turbine that drives the fan, a speed reduction mechanism coupled to the fan and rotatable by the low pressure turbine section to allow the low pressure turbine section to turn faster than the fan, wherein the low pressure turbine section includes a maximum gas path radius and the fan blades include a maximum radius, and a ratio of the maximum gas path radius to the maximum radius of the fan blades is between 0.50 and 0.55, or is greater than 0.55 and less than or equal to 0.65.