Disclosed are a method for forming a thermal barrier layer for a metallic component, which method involves forming a ceramic coat in which at least in part aluminum oxide and titanium oxide are disposed, the aluminum oxide and the titanium oxide being introduced by infiltration of aluminum-containing and titanium-containing particles or substances or by physical vapor deposition.

Disclosed herein is a method of coating, comprising providing an article having an internal passage therein to be coated; electrolytically applying a first layer that comprises chromium or a chromium alloy onto a surface of the internal passage; electrolytically applying a second layer comprising aluminum or an aluminum alloy onto the first layer; and heat treating the article to promote interdiffusion between the first layer and the second layer.

An arrangement comprising a component (203) adjacent to a ceramic matrix composite in a gas turbine engine is shown. The component comprises a nickel-base superalloy substrate (301) and a cobalt-modified beta-nickel-aluminide coating (302) on the substrate to prevent interdiffusion between the substrate and the ceramic matrix composite. The substrate is coated by depositing a cobalt layer on the substrate, depositing an aluminium layer on the cobalt layer and then forming a cobalt-modified beta nickel aluminide coating.

An aircraft engine-part including at least a metal substrate and a protective coating for protection against erosion that is present on the substrate, the coating including at least one phase including at least chromium at an atom content greater than or equal to 45% and carbon at an atom content lying in the range 5% to 20%, the phase including Cr.sub.7C.sub.3 and Cr.sub.23C.sub.6 chromium carbides. A method of fabricating such a part in which electroplating is used to deposit a coating composition on the part and the part is subjected to heat treatment at a temperature lying in the range 250 C to 70 C.

A piston capable of reducing undesirable knock, reducing hydrocarbon emissions, and providing more complete combustion, is provided. The piston includes a multilayer coating having a thickness of 500 microns or less disposed on an upper combustion surface. The coating includes a bond layer including nickel disposed on the upper combustion surface. A thermal barrier layer including a ceramic composition is disposed on the bond layer. A sealant layer formed of metal is disposed on the thermal barrier layer. A catalytic layer including at least one of platinum, ruthenium, rhodium, palladium, osmium, and iridium is disposed on the sealant layer. The catalytic layer can be disposed on select regions or the entire upper combustion surface to promote combustion through a catalyzed reaction.

A method of forming a thermal barrier coating onto a surface of a ferrous alloy or nickel alloy component part involves depositing a layer of hollow microspheres to a surface of the component part or to a previously deposited layer of hollow microspheres through heating and cooling of a metallic precursor setting layer composed of copper, a copper alloy, or a nickel alloy. Once deposited in place, the layer(s) of hollow microspheres are heated to sinter the hollow microspheres to each other and to the surface of the ferrous alloy or nickel alloy component part to form an insulating layer.

A thermal barrier coated metallic article includes a platinum-group metal enriched outer layer on the article. The surface of the outer layer has a microstructure including a plurality of projections extending away from the metallic article. A thin adherent layer of oxide is formed on the outer layer of the metallic article. A ceramic coating is provided on the oxide layer on the surface on and around the projections. The ceramic coating includes a plurality of columnar ceramic grains which extend through the full thickness of the ceramic coating. The grains are arranged in clusters separated by gaps. The grains deposited around the projections are generally blocked. The projections reduce the stress in the ceramic coating near the interface with the adherent layer of oxide and also reduce the stress in the adherent layer of oxide and hence increase the working life of the thermal barrier coating system.

A vane device for a gas turbine having an inner shroud and an outer shroud, an aerofoil arranged between the inner shroud and the outer shroud, the aerofoil and/or inner shroud and/or an outer shroud having a first layer of MCrAlY coating over a substrate, a coated surface section which is coated with a thermal barrier coating over the first layer of MCrAlY coating, a second layer of MCrAlY coating provided between the first layer of MCrAlY and the thermal barrier coating of the coated surface section.