Methods for preparing an environmental barrier coating and the resulting coating are provided. The methods and products include the incorporation of a continuous ceramic inner layer and a segmented ceramic outer layer on a CMC component. The segmented ceramic outer layer may be formed by thermal spray techniques. The coating is more stable at higher temperatures and provides for a longer lifetime of the coated component.

Methods for preparing an environmental barrier coating and the resulting coating are provided. The methods and products include the incorporation of a continuous ceramic inner layer and a segmented ceramic outer layer on a CMC component. The segmented ceramic outer layer may be formed by thermal spray techniques. The coating is more stable at higher temperatures and provides for a longer lifetime of the coated component.

In one example, a method for forming an environmental barrier coating (EBC) and/or abradable coating on a substrate. The method may include depositing a coating on a ceramic or ceramic matrix composite (CMC) substrate to form an as-deposited coating, wherein the coating includes at least one of an environmental barrier coating (EBC) and an abradable coating. The method further comprises heat treating the as-deposited coating at or above a first temperature for a first period of time following the deposition of the as-deposited coating on the substrate, wherein heat treating the as-deposited coating includes heating the as-deposited coating to or above the first temperature at a controlled rate. The heat treatment may be configured to at least one of decrease the open pores and/or microcracks of the heat-treated coating compared to the as-deposited coating or control a grain size of the heat-treated coating.

In one example, a method for forming an environmental barrier coating (EBC) and/or abradable coating on a substrate. The method may include depositing a coating on a ceramic or ceramic matrix composite (CMC) substrate to form an as-deposited coating, wherein the coating includes at least one of an environmental barrier coating (EBC) and an abradable coating. The method further comprises heat treating the as-deposited coating at or above a first temperature for a first period of time following the deposition of the as-deposited coating on the substrate, wherein heat treating the as-deposited coating includes heating the as-deposited coating to or above the first temperature at a controlled rate. The heat treatment may be configured to at least one of decrease the open pores and/or microcracks of the heat-treated coating compared to the as-deposited coating or control a grain size of the heat-treated coating.

A method of forming an impurity barrier layer on a CMC substrate may include introducing, to a heated plume of a thermal spray gun, a composite feedstock that includes a first coating material including a plurality of first particles; and a second coating material that may be different from the first coating material, where the second coating material at least partially encapsulates at least a portion of respective surfaces of the plurality of first particles; and directing, using the heated plume, at least the first coating material to a surface of a CMC substrate to deposit an impurity barrier layer including at least the first coating material.

A method of forming an impurity barrier layer on a CMC substrate may include introducing, to a heated plume of a thermal spray gun, a composite feedstock that includes a first coating material including a plurality of first particles; and a second coating material that may be different from the first coating material, where the second coating material at least partially encapsulates at least a portion of respective surfaces of the plurality of first particles; and directing, using the heated plume, at least the first coating material to a surface of a CMC substrate to deposit an impurity barrier layer including at least the first coating material.

A method of fabricating a coating includes providing a ceramic matrix composite that includes SiC fibers disposed in a SiC matrix, depositing a base slurry on the ceramic matrix composite, wherein the base slurry contains powders of a metal oxide, at least one of silicon carbide, silicon nitride, or free silicon, and barium-magnesium-aluminosilicate in a first carrier fluid, drying the deposited base slurry to produce a base green layer, depositing a transition slurry on the base green layer, wherein the transition slurry contains powders of a metal oxide, at least one of silicon carbide, silicon nitride, or free silicon, at least one of zirconium carbide, zirconium nitride, or zirconium oxide, and barium-magnesium-aluminosilicate in a second carrier fluid, drying the deposited transition slurry to produce a transition green layer, and forming a consolidated coating on the ceramic matrix composite by heating the base green layer and the at least one transition green layer to cause chemical reactions that convert the powders to metal-silicon-oxygen rich phase and metal-zirconium-oxygen rich phase.

A method for coating a substrate includes spraying a combination of powders. The combination of powders includes: Hf.sub.0.5Si.sub.0.5O.sub.2; Zr.sub.0.5Si.sub.0.5O.sub.2; and, optionally, at least one of HfO.sub.2 and ZrO.sub.2. A molar ratio of said Hf.sub.0.5Si.sub.0.5O.sub.2 and HfO.sub.2 combined to said Zr.sub.0.5Si.sub.0.5O.sub.2 and ZrO.sub.2 combined is from 2:1 to 4:1. A molar ratio of said Hf.sub.0.5Si.sub.0.5O.sub.2 to said HfO.sub.2 is at least 1:3.

A structure for high temperature applications includes a base structure which includes a ceramic composite material, and a coating of a metal-semimetal compound, a metal boride, a metal carbide and/or a metal nitride. Furthermore, a production method and a coating device produces structures which resist high temperature applications with higher process temperatures and difficult chemical conditions.

A structure for high temperature applications includes a base structure which includes a ceramic composite material, and a coating of a metal-semimetal compound, a metal boride, a metal carbide and/or a metal nitride. Furthermore, a production method and a coating device produces structures which resist high temperature applications with higher process temperatures and difficult chemical conditions.