An article may include a substrate including a ceramic or a ceramic matrix composite. The substrate defines a hot side surface configured to face a heated gas environment and a cool side surface opposite the hot side surface. The article also includes a cool side coating on the cool side surface. The cool side coating comprises at least one material having a flow temperature equal to or slightly less than a temperature of the heated gas environment.

An article may include a substrate including a ceramic or a ceramic matrix composite. The substrate defines a hot side surface configured to face a heated gas environment and a cool side surface opposite the hot side surface. The article also includes a cool side coating on the cool side surface. The cool side coating comprises at least one material having a flow temperature equal to or slightly less than a temperature of the heated gas environment.

In one example, a method for forming an environmental barrier coating (EBC) on a substrate. The method may include heating the substrate before and/or during deposition of EBC on the substrate using an external burner and/or resistive electrical heating. Additionally, or alternatively, the as-deposited EBC may be heat treated using an external burner and/or resistive electrical heating. In some examples, the techniques of the disclosure are configured to increase or otherwise tailor the amount of crystalline phase in the EBC.

In one example, a method for forming an environmental barrier coating (EBC) on a substrate. The method may include heating the substrate before and/or during deposition of EBC on the substrate using an external burner and/or resistive electrical heating. Additionally, or alternatively, the as-deposited EBC may be heat treated using an external burner and/or resistive electrical heating. In some examples, the techniques of the disclosure are configured to increase or otherwise tailor the amount of crystalline phase in the EBC.

An environmental resistant coating member includes a SiC long fiber-reinforced ceramics substrate and an environmental barrier coating layer provided on the whole surface of the SiC long fiber-reinforced ceramics substrate. The environmental barrier coating layer includes a SiAlON bonding layer laminated on the SiC long fiber-reinforced ceramics substrate, a mullite layer laminated on the SiAlON bonding layer, a reaction inhibition layer laminated on the mullite layer, and a gradient layer formed on the reaction inhibition layer that gradually changes from a rare-earth disilicate to a rare-earth monosilicate. The reaction inhibition layer includes at least one of an alumina layer, a garnet layer, and a rare-earth (mono)silicate layer. When the reaction inhibition layer includes two or more of these layers, the layers are formed in the order of the alumina layer, the garnet layer, and the rare-earth (mono)silicate layer from a mullite layer side toward a gradient layer side.

An environmental resistant coating member includes a SiC long fiber-reinforced ceramics substrate and an environmental barrier coating layer provided on the whole surface of the SiC long fiber-reinforced ceramics substrate. The environmental barrier coating layer includes a SiAlON bonding layer laminated on the SiC long fiber-reinforced ceramics substrate, a mullite layer laminated on the SiAlON bonding layer, a reaction inhibition layer laminated on the mullite layer, and a gradient layer formed on the reaction inhibition layer that gradually changes from a rare-earth disilicate to a rare-earth monosilicate. The reaction inhibition layer includes at least one of an alumina layer, a garnet layer, and a rare-earth (mono)silicate layer. When the reaction inhibition layer includes two or more of these layers, the layers are formed in the order of the alumina layer, the garnet layer, and the rare-earth (mono)silicate layer from a mullite layer side toward a gradient layer side.

A filter including a plurality of pillar-shaped honeycomb structure segments made of porous ceramics, side faces of the segments being bonded together via a bonding material, wherein each of the pillar-shaped honeycomb structure segments includes an outer peripheral side wall, and partition walls partitioning a plurality of cells extending from a first end face to a second end face, and in each of the pillar-shaped honeycomb structure segments, an average porosity of the outer peripheral side wall is lower than that of the partition walls.

A filter including a plurality of pillar-shaped honeycomb structure segments made of porous ceramics, side faces of the segments being bonded together via a bonding material, wherein each of the pillar-shaped honeycomb structure segments includes an outer peripheral side wall, and partition walls partitioning a plurality of cells extending from a first end face to a second end face, and in each of the pillar-shaped honeycomb structure segments, an average porosity of the outer peripheral side wall is lower than that of the partition walls.

An article includes a substrate, a bond coat on the substrate, and a multilayer environmental barrier coating (EBC) on the bond coat. The multilayer EBC includes a first EBC layer defining a first thickness and a second EBC layer defining a second thickness. The first EBC layer includes a first rare earth disilicate and a first concentration of a sintering aid that includes alumina. The second EBC layer includes a second rare earth disilicate and a second concentration of the sintering aid that includes alumina, less than the first concentration of the sintering aid.

An article includes a substrate, a bond coat on the substrate, and a multilayer environmental barrier coating (EBC) on the bond coat. The multilayer EBC includes a first EBC layer defining a first thickness and a second EBC layer defining a second thickness. The first EBC layer includes a first rare earth disilicate and a first concentration of a sintering aid that includes alumina. The second EBC layer includes a second rare earth disilicate and a second concentration of the sintering aid that includes alumina, less than the first concentration of the sintering aid.