A gas turbine engine includes a plurality of rotating components housed within a compressor section and a turbine section. A first tap is connected to the compressor section and configured to deliver air at a first pressure. A heat exchanger is connected downstream of the first tap. A flowpath is defined between a rotating surface and a non-rotating surface. The flowpath is connected downstream of the heat exchanger and is configured to deliver air to at least one of the plurality of rotating components. At least a portion of the non-rotating surface and the rotating surface includes a base metal. An insulation material is disposed on a surface along the flowpath.

A space filler for forming a fibrous preform may comprise an additively manufactured ceramic material. The additively manufactured ceramic material may define a plurality of pores. A shape of the additively manufactured ceramic material may complement a shape of a void formed by fibrous regions of the fibrous preform.

In one example, an article including a metallic substrate; and an abradable coating on the metallic substrate, the abradable coating including a plurality of abradable layers in an alternating arrangement with a plurality of CMAS resistant layers, wherein the plurality of CMAS resistant layers are configured to react with molten CMAS to form a stable phase.

A structure which is resistant to corrosion at high temperatures comprises a layer of ruthenium and/or ruthenium alloy and a layer of a refractory metal having a high strength at high temperatures, such as rhenium. Further, the structure may include a layer of ceramic such as zirconia or hafnia on the exposed face of the ruthenium layer. Alternative embodiments of the present invention include a catalyst formed from a low strength support structure with a first metal layer and a second ruthenium catalytic layer on top of the first metal layer. Another alternative embodiment of the present invention includes the formation of high purity ruthenium electrodes that are resistant to corrosion at high temperatures.

A high entropy ceramic (HEC) composition includes at least three different rare earth (RE) oxides and at least one of hafnium dioxide (HfO.sub.2) and zirconia oxide (ZrO.sub.2). The at least three different rare earth oxides being equimolar fractions. In one aspect, the high entropy ceramic (HEC) composition can be used in a thermal barrier coating.

A thermal barrier coated component, such as a turbine blade formed from a superalloy substrate, includes a thermal barrier coating applied onto the substrate. A metallic bond coat layer is on the substrate and includes rare-earth luminescent dopants. A ceramic top coat layer is on the bond coat layer. A temperature sensing thermally grown oxide (TGO) layer is formed at the interface of the bond coat layer and ceramic top coat layer. The temperature sensing TGO layer includes grown rare-earth luminescent ions migrated from the metallic bond coat layer in an amount sufficient to enable luminescence sensing of the TGO layer for real-time phosphor thermometry temperature measurements at the TGO layer.

The invention relates to a ceramic sealing system between a rotor blade (120) and a housing (I). A small porous zirconium oxide layer (II) on a turbine rotor blade, which zirconium oxide layer faces a ceramic layer system (15′, 15″) of higher porosity, achieves durable sealing systems. The housing (I″) has a metal substrate (7), a metal adhesion-promoting layer (10), and a thick, outer, ceramic layer (15′, 15″) based on zirconium oxide, in particular having a porosity 2≥14%.

The present invention relates to zirconium oxide powder for thermal spraying and a method for its manufacture. Furthermore, the present invention relates to thermal insulation layers, which are obtained using the zirconium oxide powder according to the invention.

In one example, an article including a metallic substrate; and an abradable coating on the metallic substrate, the abradable coating including a plurality of abradable layers in an alternating arrangement with a plurality of CMAS resistant layers, wherein the plurality of CMAS resistant layers are configured to react with molten CMAS to form a stable phase.

An article includes a substrate, a bond coat layer disposed on the substrate, and a layer of networked ceramic nanofibers disposed on the bond coat layer.