An environmental barrier coating, comprising a substrate containing silicon; an environmental barrier layer applied to said substrate; said environmental barrier layer comprising a rare earth composition.

A method of applying a protective coating to a substrate includes the steps of: providing a turbine engine component substrate formed of a ceramic matrix composite material, forming an environmental barrier coating layer including a rare earth disilicate material directly on the substrate, treating an outer surface of the environmental barrier coating layer to form a thermal barrier coating layer including a porous rare earth monociliate material directly on the environmental barrier coating layer. The step of treating the outer surface is performed using a thermal process consisting of the application of heat or a chemical-thermal process consisting of the application of heat and a chemical. The method further includes infiltrating at least a portion of the pores with a metal solution or suspension.

A method of applying a protective coating to a substrate includes the steps of: providing a turbine engine component substrate formed of a ceramic matrix composite material, forming an environmental barrier coating layer including a rare earth disilicate material directly on the substrate, treating an outer surface of the environmental barrier coating layer to form a thermal barrier coating layer including a porous rare earth monociliate material directly on the environmental barrier coating layer. The step of treating the outer surface is performed using a thermal process consisting of the application of heat or a chemical-thermal process consisting of the application of heat and a chemical. The method further includes infiltrating at least a portion of the pores with a metal solution or suspension.

A protective coating system includes a turbine engine component substrate formed of a ceramic matrix composite material, an environmental barrier coating layer including a rare earth disilicate material formed directly on the substrate, and a thermal barrier coating layer including a porous rare earth monosilicate material having a metal silicate material infiltrated within at least a portion of the pores formed directly on the environmental barrier coating layer.

A protective coating system includes a turbine engine component substrate formed of a ceramic matrix composite material, an environmental barrier coating layer including a rare earth disilicate material formed directly on the substrate, and a thermal barrier coating layer including a porous rare earth monosilicate material having a metal silicate material infiltrated within at least a portion of the pores formed directly on the environmental barrier coating layer.

An article for high temperature service is presented herein. One embodiment is an article including a substrate having a silicon-bearing ceramic matrix composite; and a layer disposed over the substrate, wherein the layer includes silicon and a dopant, the dopant including aluminum. In another embodiment, the article includes a ceramic matrix composite substrate, wherein the composite includes a silicon-bearing ceramic and a dopant, the dopant including aluminum; a bond coat disposed over the substrate, where the bond coat includes elemental silicon, a silicon alloy, a silicide, or combinations including any of the aforementioned; and a coating disposed over the bond coat, the coating including a silicate (such as an aluminosilicate or rare earth silicate), yttria-stabilized zirconia, or a combination including any of the aforementioned.

An article for high temperature service is presented herein. One embodiment is an article including a substrate having a silicon-bearing ceramic matrix composite; and a layer disposed over the substrate, wherein the layer includes silicon and a dopant, the dopant including aluminum. In another embodiment, the article includes a ceramic matrix composite substrate, wherein the composite includes a silicon-bearing ceramic and a dopant, the dopant including aluminum; a bond coat disposed over the substrate, where the bond coat includes elemental silicon, a silicon alloy, a silicide, or combinations including any of the aforementioned; and a coating disposed over the bond coat, the coating including a silicate (such as an aluminosilicate or rare earth silicate), yttria-stabilized zirconia, or a combination including any of the aforementioned.

Granules for a roof coating, wherein said granules comprise particles that have a coating, wherein said coating comprises at least one layer of an inorganic powder in a binder, wherein said inorganic powder has a d50 grain size of from 0.5 to 25 μm, and wherein a hydrophobizing and/or oleophobizing agent is present on said coating.

Granules for a roof coating, wherein said granules comprise particles that have a coating, wherein said coating comprises at least one layer of an inorganic powder in a binder, wherein said inorganic powder has a d50 grain size of from 0.5 to 25 μm, and wherein a hydrophobizing and/or oleophobizing agent is present on said coating.

A method for forming a high temperature coating includes forming a pre-sintered ceramic coating on a ceramic composite substrate. The pre-sintered ceramic coating includes a plurality of ceramic particles. The method further includes sintering at least a portion of the pre-sintered ceramic coating by heating the portion of the pre-sintered ceramic coating to a sintering temperature of the plurality of ceramic particles using joule heating. The sintering temperature is greater than about 1000 degrees Celsius (° C.).