Abstract: Environmental barrier coatings having CMAS mitigation capability for silicon-containing components. In one embodiment, the barrier coating includes a bond coat layer comprising aluminide-alumina TGO; and an outer layer selected from the group consisting of AeAl2O19, AeHfO3, AeZrO3, ZnAl2O4, MgAl2O4, Ln4Al2O9, Lna4Ga2O9, Ln3Al5O12, Ln3Ga5O12, Ga2O3, HfO2, and LnPO4.

Abstract: Methods for repairing barrier coatings involving providing a component having a barrier coating including at least one damaged portion, removing the damaged portion of the barrier coating leaving a void, applying a replacement tape cast barrier coating to the void of the component, and sintering the component having the replacement tape cast barrier coating layer.

Abstract: Environmental barrier coatings for high temperature ceramic components, the barrier coatings including a bond coat layer including silicon; an optional silica layer; at least one transition layer including: from about 85% to about 100% by volume of the transition layer of a primary transition material selected from mullite, BSAS, or a mullite/BSAS mixture; and from 0% to about 15% by volume of the transition layer of a secondary material selected from rare earth oxide, rare earth disilicate, rare earth monosilicate, rare earth elements, rare earth containing aluminosilicate glass, rare earth and alkaline earth containing aluminosilicate glass, rare earth aluminates, phosphorous pentoxide, phosphorous containing aluminosilicate glass, phosphorous and alkaline earth containing aluminosilicate glass, aluminum orthophosphate, aluminum oxide, and combinations thereof; and an outer layer including: from about 85% to about 100% by volume of the outer layer of a primary outer material comprising BSAS; and from 0% to

Abstract: Methods or making an environmental barrier coating using a sintering aid including combining at least water, a primary transition material selected from mullite, BSAS, or a mullite/BSAS mixture, and a slurry sintering aid to produce a transition layer slurry; applying the transition layer slurry to a ceramic component; combining at least water, and a primary outer material of BSAS to produce an outer layer slurry; applying the outer layer slurry to the component having the applied transition layer slurry; and sintering the component to produce the environmental barrier coating having at least a transition layer and an outer layer where the transition layer comprises a porosity of from 0% to about 30% by volume of the transition layer, and the outer layer comprises a porosity of from 0% to about 15% by volume of the outer layer.

Abstract: Environmental barrier coatings having CMAS mitigation capability for silicon-containing components. In one embodiment, the barrier coating includes a bond coat layer comprising silicon or silicide, and an outer layer selected from the group consisting of Ln4Al2O9, and Lna4Ga2O9.

Abstract: Environmental barrier coating having CMAS mitigation capability for oxide components. In one embodiment, the barrier coating includes an outer layer selected from AeAl2O19, AeHfO3, AeZrO3, ZnAl2O4, MgAl2O4, Ln4Al2O9, Lna4Ga2O9, Ln3Al5O12, Ln3Ga5O12, and Ga2O3.

Abstract: Methods for improving surface roughness of an environmental barrier coating including providing a component having a plasma sprayed environmental barrier coating, applying an outer layer repair slurry to the environmental barrier coating of the component, drying the environmental barrier coating having the applied outer layer repair slurry; and sintering the component to produce a component having an improved surface roughness where the outer layer repair slurry includes water; a primary outer material of BSAS; and a slurry sintering aid selected from rare earth nitrate, rare earth acetate, rare earth chloride, rare earth oxide, ammonium phosphate, phosphoric acid, polyvinyl phosphonic acid, and combinations thereof

Abstract: Methods for improving surface roughness of an environmental barrier coating involving providing a component having a plasma sprayed environmental barrier coating; applying a slurry to the environmental barrier coating of the component, the slurry being a transition layer slurry or an outer layer slurry; drying the environmental barrier coating having the applied slurry; and sintering the component to produce a component having an improved surface roughness wherein the slurry includes water; a primary transition material, or a primary outer material; and a slurry sintering aid selected from iron oxide, gallium oxide, aluminum oxide, nickel oxide, titanium oxide, boron oxide, alkaline earth oxides, carbonyl iron, iron metal, aluminum metal, boron, nickel metal, iron hydroxide, gallium hydroxide, aluminum hydroxide, nickel hydroxide, titanium hydroxide, alkaline earth hydroxides, iron carbonate, gallium carbonate, aluminum carbonate, nickel carbonate, boron carbonate, alkaline earth carbonates, iron oxalate, gal

Abstract: Methods for improving surface roughness of an environmental barrier coating including providing a component having a plasma sprayed environmental barrier coating; applying a slurry to the environmental barrier coating of the component, the slurry being a transition layer slurry or an outer layer slurry; drying the environmental barrier coating having the applied slurry; and sintering the component to produce a component having an improved surface roughness where the slurry includes a solvent; a primary transition material, or a primary outer material; and a slurry sintering aid selected from iron oxide, gallium oxide, aluminum oxide, nickel oxide, titanium oxide, boron oxide, alkaline earth oxides, carbonyl iron, iron metal, aluminum metal, boron, nickel metal, iron hydroxide, gallium hydroxide, aluminum hydroxide, nickel hydroxide, titanium hydroxide, alkaline earth hydroxides, iron carbonate, gallium carbonate, aluminum carbonate, nickel carbonate, boron carbonate, alkaline earth carbonates, iron oxalate, g

Abstract: Water based slurry compositions for making an environmental barrier coating including from about 1 wt % to about 99.9 wt % water; from about 0.1 wt % to about 72 wt % primary material; and from about 0.1 wt % to about 25 wt % slurry sintering aid.

Abstract: Methods for making an environmental barrier coating using a sintering aid involving applying a bond coat layer to the ceramic component; combining at least an organic solvent, a primary transition material selected from a rare earth disilicate, or a doped rare earth disilicate, and at least one slurry sintering aid to produce a transition layer slurry; combining at least an organic solvent, and a primary outer material selected from a rare earth monosilicate or a doped rare earth monosilicate to produce an outer layer slurry; combining at least an organic solvent, and a primary compliant material comprising BSAS or a rare earth doped BSAS to produce a compliant layer slurry; applying at least the transition layer slurry, and any one or more of the outer layer slurry, and the compliant layer slurry to the component; and sintering the component to produce the environmental barrier coating having at least the bond coat layer, a transition layer and any of an outer layer or a compliant layer whereby a reaction be

Abstract: Methods for making an environmental barrier coating using a sintering aid including combining at least an organic solvent, and a primary transition material such as a rare earth disilicate, or a doped rare earth disilicate to produce a transition layer slurry; applying the transition layer slurry to the component; drying the component having the applied transition layer slurry; infiltrating a sol-gel solution containing an aqueous solution of a water soluble salt sintering aid, or an organic solvent solution of a solvent soluble salt sintering aid into the applied slurry; and sintering the component to produce the environmental barrier coating having at least the bond coat layer, and a transition layer wherein during sintering, a reaction between the primary transition material and the sintering aid results in the transition layer having a porosity of from 0% to about 15% by volume of the transition layer.

Abstract: Organic solvent based slurry compositions for making an environmental barrier coating including from about 6.8 wt % to about 96.1 wt % solvent; from about 3.9 wt % to about 93.2 wt % primary material; and from about 0.01 wt % to about 20 wt % slurry sintering aid.

Abstract: Methods for making an environmental barrier coating using a sintering aid including combining at least water, and a primary transition material selected from mullite, BSAS, or a mullite/BSAS mixture to produce a transition layer slurry; applying the transition layer slurry to a ceramic component; drying the component having the applied transition layer slurry; infiltrating a sol-gel solution into the applied transition layer slurry; combining at least water, and a primary outer material of BSAS to produce an outer layer slurry; applying the outer layer slurry to the component having the applied transition layer slurry; and sintering the component to produce the environmental barrier coating having at least a transition layer and an outer layer where the transition layer comprises a porosity of from 0% to about 30% by volume of the transition layer, and the outer layer comprises a porosity of from 0% to about 15% by volume of the outer layer.

Abstract: Methods for making an environmental barrier coating using a sintering aid involving: applying a bond coat layer to the ceramic component; combining at least water, and a primary transition material selected from a rare earth disilicate, or a doped rare earth disilicate to produce a transition layer slurry; applying the transition layer slurry to the bon coat layer; drying the component having the applied transition layer slurry; infiltrating a sol-gel solution including an aqueous solution of a water soluble salt sintering aid, or an organic solvent solution of a solvent soluble salt sintering aid into the applied slurry; and sintering the component to produce the environmental barrier coating having at least the bond coat layer, and a transition layer wherein during sintering a reaction between the primary transition material and the sintering aid results in the transition layer having a porosity of from 0% to about 15% by volume of the transition layer.

Abstract: Environmental barrier coatings for high temperature ceramic components including: a bond coat layer; an optional silica layer; and at least one transition layer including: from about 85% to about 100% by volume of the transition layer of a primary transition material selected from a rare earth disilicate, or a doped rare earth disilicate; and from 0% to about 15% by volume of the transition layer of a secondary material selected from Fe2O3, iron silicates, rare earth iron oxides, Al2O3, mullite, rare earth aluminates, rare earth aluminosilicates, TiO2, rare earth titanates, Ga2O3, rare earth gallates, NiO, nickel silicates, rare earth nickel oxides, Lnb metals, Lnb2O3, Lnb2Si2O7, Lnb2SiO5, borosilicate glass, alkaline earth silicates, alkaline earth rare earth oxides, alkaline earth rare earth silicates, and mixtures thereof; where the transition layer is applied to the component as a slurry including at least water, the primary transition material and at least one slurry sintering aid, and where a reaction b

Abstract: Slurry compositions for making an environmental barrier coating including from about 9 wt % to about 81 wt % water; from about 3 wt % to about 72 wt % primary material; and from about 0.1 wt % to about 18 wt % slurry sintering aid, and environmental barrier coatings including such compositions.

Abstract: Environmental barrier coatings for high temperature ceramic components including a bond coat layer; an optional silica layer; and at least one transition layer including: from about 85% to about 100% by volume of the transition layer of a primary transition material including a rare earth disilicate, or a doped rare earth disilicate; and from 0% to about 15% by volume of the transition layer of a secondary material selected from Fe2O3, iron silicates, rare earth iron oxides, Al2O3, mullite, rare earth aluminates, rare earth aluminosilicates, TiO2, rare earth titanates, Ga2O3, rare earth gallates, NiO, nickel silicates, rare earth nickel oxides, Lnb metals, Lnb2O3, Lnb2Si2O7, Lnb2SiO5, borosilicate glass, alkaline earth silicates, alkaline earth rare earth oxides, alkaline earth rare earth silicates, and mixtures thereof; where the transition layer is applied to the component as a slurry including at least an organic solvent, the primary transition material and at least one slurry sintering aid, and where a re

Abstract: A method for applying a NiAl based bond coat and a diffusion aluminide coating to a metal substrate is disclosed. The method comprises providing a superalloy substrate, the superalloy substrate having an external surface; and optionally cleaning the external surface of the superalloy substrate. The method further comprises coating a portion of the external surface of the superalloy substrate, by physical vapor deposition with a layer of a NiAl based metal alloy, wherein the deposited NiAl based metal alloy includes a controlled amount of about 6 to 25 weight percent aluminum and additionally the deposited aluminum level of the NiAl based metal alloy is controlled to be about 50-100% of its final level after aluminizing to form a coated external portion; and subsequently, simultaneously aluminizing the coated external portion and a different surface of the superalloy substrate.

Abstract: Calcium magnesium aluminosilcate (CMAS) mitigation compositions selected from zinc aluminate spinel, alkaline earth zirconates, alkaline earth hafnates, rare earth gallates, beryl, and combinations thereof wherein the CMAS mitigation composition is included as a separate CMAS mitigation layer in an environmental barrier coating for a high temperature substrate component.