Abstract: Methods of forming sintered coatings are provided, along with the resulting coatings on a substrate. The sintered coating may comprise a rare earth compound and a sintering aid, with the rare earth compound has the formula: A1?bBbZ1?dDdMO6 where A is Al, Ga, In, Sc, Y, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Fe, Cr, Co, Mn, Bi, or a mixture thereof; b is 0 to about 0.5; Z is Hf, Ti, or a mixture thereof; D is Zr, Ce, Ge, Si, or a mixture thereof; d is 0 to about 0.5; and M is Ta, Nb, or a mixture thereof. The coating may be densified at a sintering temperature, such as 1300° C. to 1600° C.

Abstract: A coated component, along with methods of its formation and use, is provided. The coated component may include a substrate having a surface with a plurality of cavities defined therein, a bond coating (e.g., including a silicon material) on the surface of the substrate within the cavities, and an environmental barrier coating over the surface of the substrate and encasing the bond coating within the cavities such that the bond coating, when melted, is contained within the cavities. Such a coated component may be, in one embodiment, a turbine component, such as a CMC component for use in a hot gas path of a gas turbine engine.

Abstract: A method for processing a component is provided and includes masking a first portion of the component with a maskant. The maskant includes a slurry having a plurality of particles in a fluid carrier. The plurality of particles comprises at least one of silicon, carbon, one or more rare earth disilicates, monosilicates or oxides, and combinations thereof. The method includes depositing a silicon-based coating on a second portion of the component via a chemical vapor deposition process and removing the maskant and any overlying silicon-based coating from the first portion of the component.

Abstract: A composition is provided that includes a silicon-containing material (e.g., a silicon metal and/or a silicide) and about 0.001% to about 85% of a Ga-containing compound, an In-containing compound, or a mixture thereof. The silicon-based layer can be a bond coating directly on the surface of the substrate. Alternatively or additionally, the silicon-based layer can be an outer layer defining a surface of the substrate, with an environmental barrier coating on the surface of the substrate. A coated component is also provided, as well as a method for coating a ceramic component. Gas turbine engines are also provided that include such a ceramic component.

Abstract: Environmental barrier coatings including a bondcoat layer including silicon and a rare earth silicate-based hermetic layer and rare earth silicate-based non-hermetic layer are provided. The rare earth silicate-based hermetic layer is deposited on the bondcoat via a thermal spray process and has an elastic modulus ranging from 100 GPa to 180 GPa. The at least one rare earth silicate-based non-hermetic layer is deposited on the rare earth silicate-based hermetic layer and has an elastic modulus ranging from 50 GPa to 100 GPa. Coated gas turbine engine components and methods for coating gas turbine engine components are also provided.

Abstract: Methods are provided for forming a coating on a surface of a substrate. The method may include: applying a negative charge to the surface of the substrate; electrophoretically depositing a slurry layer onto the surface of the substrate; and densifying the slurry layer on the surface of the substrate at a sintering temperature to form a sintered layer of the coating. The slurry layer may include a plurality of EBC material particles, a cationic polyelectrolyte, a plurality of polymeric binder particles, and a solvent. The plurality of EBC material particles may comprise barium strontium aluminosilicate (BSAS), mullite, silicon, rare earth compounds, or combinations thereof.

Abstract: Compounds are generally provided, which may be particularly used to form a layer in a coating system. In one embodiment, the compound may have the formula: AxBbLn1-x-bHf1-t-dTitDdMO6, where: A is Al, Ga, In, Sc, Y, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Fe, Cr, Co, Mn, Bi, or a mixture thereof; x is about 0.01 to about 0.99; b is 0 to about 0.5, with 1-x-b being 0 to about 0.99 such that Ln is present in the compound; Ln is a rare earth or a mixture thereof that is different than A; t is 0 to about 0.99; D is Zr, Ce, Ge, Si, or a mixture thereof; d is 0 to about 0.5; the sum of t and d is less than 1 such that Hf is present in the compound; and M is Ta, Nb, or a mixture thereof.

Abstract: Coated components, along with methods of their formation, are provided. The coated component includes a ceramic substrate having a surface; an intermediate layer on the surface of the ceramic substrate; and an environmental barrier coating on the intermediate layer. The intermediate layer includes a carbon-sink material that inhibits accumulation of free carbon from a carbon-containing species within the intermediate layer, the ceramic substrate, or both.

Abstract: A coated component, along with methods of its formation and use, is provided. The coated component may include a substrate having a surface, a first refractory layer on the surface of the substrate, a silicon-based bond coating on the first refractory layer, and an environmental barrier coating on the silicon-based bond coating. The silicon-based bond coating includes a silicon-phase contained within a refractory phase such that, when melted, the silicon-phase is contained within the refractory phase and between the surface of the substrate and an inner surface of the environmental barrier coating.

Abstract: A composition is generally provided that includes a silicon-containing material (e.g., silicon metal and/or a silicide) and a boron-doped refractory compound, such as about 0.001% to about 85% by volume of the boron-doped refractory compound (e.g., about 1% to about 60% by volume). In one embodiment, a bond coating on a surface of a ceramic component is generally provided with the bond coating including such a composition, with the silicon-containing material is silicon metal.

Abstract: A method for processing a component is provided and includes masking a first portion of the component with a maskant. The maskant includes a slurry having a plurality of particles in a fluid carrier. The plurality of particles comprises at least one of silicon, carbon, one or more rare earth disilicates, monosilicates or oxides, and combinations thereof. The method includes depositing a silicon-based coating on a second portion of the component via a chemical vapor deposition process and removing the maskant and any overlying silicon-based coating from the first portion of the component.

Abstract: Methods of forming sintered coatings are provided, along with the resulting coatings on a substrate. The sintered coating may comprise a rare earth compound and a sintering aid, with the rare earth compound has the formula: A1?bBbZ1?dDdMO6 where A is Al, Ga, In, Sc, Y, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Fe, Cr, Co, Mn, Bi, or a mixture thereof; b is 0 to about 0.5; Z is Hf, Ti, or a mixture thereof; D is Zr, Ce, Ge, Si, or a mixture thereof; d is 0 to about 0.5; and M is Ta, Nb, or a mixture thereof. The coating may be densified at a sintering temperature, such as 1300° C. to 1600° C.

Abstract: Methods for forming a coating on a surface of a substrate are provided. The method can include: preheating the surface of the substrate; spraying a slurry suspension onto the surface of the substrate to form a coating, wherein the slurry composition comprises a rare earth compound, a sintering agent, and a solvent, wherein the rare earth compound has the formula: A1-bBbZ1-dDdMO6 where A is Al, Ga, In, Sc, Y, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Fe, Cr, Co, Mn, Bi, or a mixture thereof; b is 0 to 0.5; Z is Hf, Ti, or a mixture thereof; D is Zr, Ce, Ge, Si, or a mixture thereof; d is 0 to 0.5; and M is Ta, Nb, or a mixture thereof; and thereafter, heat treating the coating to densify the coating from an initial porosity to a sintered porosity.

Abstract: Methods for forming a coated component, along with the resulting coated components, are provided. The method may include forming a silicon-based bond coating on a surface of a substrate and forming a barrier coating on the silicon-based bond coating. The silicon-based bond coating comprises columnar grains of crystalline silicon. Chemical vapor depositing (CVD) may be used to form the silicon-based bond coating through CVD of a silicon-containing precursor at a deposition temperature and deposition pressure that causes crystallization of the silicon material during the deposition of the silicon-based bond coating. The silicon-containing precursor may be silane, monochlorosilane, dichlorosilane, and/or trichlorosilane.

Abstract: A coated substrate is provided that includes an environmental barrier coating on (e.g., directly on) a surface of a substrate (e.g., a ceramic matrix composite). The environmental barrier coating can include a barrier layer having a refractory material phase and a silicon-containing glass phase. The silicon-containing glass phase may be a continuous phase within the barrier layer (e.g., a breathable grain boundary of the barrier layer), or may be a plurality of discontinuous layers dispersed throughout the refractory material phase. The refractory material phase can include a rare earth silicate material having a rare earth component at a first atomic percent, while the silicon-containing glass phase comprises the rare earth component at a second atomic percent that is less than the first atomic percent. Methods are also provided for forming a barrier layer on a substrate.

Abstract: A coated component, along with method of forming the same, is provided. The coated component may include a substrate having a surface, a silicon-based bond coating on the surface of the substrate, and an EBC on the silicon-based bond coating. The silicon-based bond coating may include a silicon-phase contained within a refractory phase. The silicon-phase, when melted, is contained within the refractory phase and between the surface of the substrate and an inner surface of the environmental barrier coating. Such a coated component may be, in particular embodiments, a turbine component.

Abstract: Methods for tape deposition of a sacrificial coating on a CMC substrate are provided. The method comprises: applying a matrix material onto a surface of a film; drying the matrix material to remove the solvent; and transferring the dried matrix material from the film to the CMC substrate. The matrix material comprises a mixture of a rare earth silicate powder, a sintering aid, and a solvent.

Abstract: A coated substrate is provided that comprises: a substrate; and a barrier coating comprising a compound having the formula: Ln2ABO8, where Ln comprises scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, or mixtures thereof; A comprises Si, Ti, Ge, Sn, Ce, Hf, Zr, or a combination thereof; and B comprises Mo, W, or a combination thereof. In one embodiment, B comprises Mo. A gas turbine is also provided that comprises the coated substrate described above.

Abstract: Coated components, along with methods of their formation, are provided. The coated component includes a ceramic substrate having a surface; an intermediate layer on the surface of the ceramic substrate; and an environmental barrier coating on the intermediate layer. The intermediate layer includes a carbon-sink material that inhibits accumulation of free carbon from a carbon-containing species within the intermediate layer, the ceramic substrate, or both.

Abstract: Coating systems are provided for positioning on a surface of a substrate, along with the resulting coated components and methods of their formation. The coating system may include a layer having a compound of the formula: A1?bBbZ1?dDdMO6 where: A is Al, Ga, In, Sc, Y, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Fe, Cr, Co, Mn, Bi, or a mixture thereof; b is 0 to about 0.5; Z is Hf, Ti, or a mixture thereof; D is Zr, Ce, Ge, Si, or a mixture thereof; d is 0 to about 0.5; and M is Ta, Nb, or a mixture thereof.