A porous support includes a base body, a supporting layer, and a topmost layer. The supporting layer is disposed between the base body and the topmost layer, and makes contact with the topmost layer. A ratio of a porosity of the topmost layer to a porosity of the supporting layer is greater than or equal to 1.08. A ratio of a thickness of the topmost layer to a thickness of the supporting layer is less than or equal to 0.9.

A porous support includes a base body, a supporting layer, and a topmost layer. The supporting layer is disposed between the base body and the topmost layer, and makes contact with the topmost layer. A ratio of a porosity of the topmost layer to a porosity of the supporting layer is greater than or equal to 1.08. A ratio of a thickness of the topmost layer to a thickness of the supporting layer is less than or equal to 0.9.

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.

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.

In some examples, an article includes a ceramic or a ceramic or ceramic matrix composite (CMC) substrate; and an abradable coating on the CMC substrate. The abradable coating includes a plurality of first rare earth (RE) silicate layers in an alternating arrangement with a plurality of second RE silicate layers, wherein the first RE silicate layers include a rare earth monosilicate and the second RE silicate layers include a rare earth disilicate, and wherein the first RE silicate layers include a greater concentration of the rare earth monosilicate than the second RE silicate layers.

In some examples, an article includes a ceramic or a ceramic or ceramic matrix composite (CMC) substrate; and an abradable coating on the CMC substrate. The abradable coating includes a plurality of first rare earth (RE) silicate layers in an alternating arrangement with a plurality of second RE silicate layers, wherein the first RE silicate layers include a rare earth monosilicate and the second RE silicate layers include a rare earth disilicate, and wherein the first RE silicate layers include a greater concentration of the rare earth monosilicate than the second RE silicate layers.

The invention discloses a biologically active zirconia denture has a gradient structure, the gradient structure consisting of a biomimetic nano-gradient biologically active outer surface layer, the nano-gradient outer surface layer is composed of zirconia nanocrystals and a plurality of nanopores penetrating gradiently through the layer, a micron-gradient biocompatible inner layer, the micron-gradient inner surface layer is composed of zirconia microncrystals and a plurality of micronpores penetrating gradiently through the layer, a dense micron-gradient biocompatible matrix structure, a uniform gradient transition is formed at the interface between the nano-gradient outer layer and the micron-gradient inner layer, and the micron-gradient inner layer and the matrix. The invention has the advantages of high strength, high toughness, low friction coefficient, low abrasion to the teeth, good biocompatibility and biological activity.

A plasma processing device member according to the disclosure includes a base material and a film formed of a rare-earth element oxide, or a rare-earth element fluoride, or a rare-earth element oxyfluoride, or a rare-earth element nitride, the film being disposed on at least part of the base material. The film includes a surface to be exposed to plasma, the surface having an arithmetic mean roughness Ra of 0.01 μm or more and 0.1 μm or less, the surface being provided with a plurality of pores, and a value obtained by subtracting an average equivalent circle diameter of the pores from an average distance between centroids of adjacent pores is 28 μm or more and 48 μm or less. A plasma processing device according to the disclosure includes the plasma processing device member described above.

A plasma processing device member according to the disclosure includes a base material and a film formed of a rare-earth element oxide, or a rare-earth element fluoride, or a rare-earth element oxyfluoride, or a rare-earth element nitride, the film being disposed on at least part of the base material. The film includes a surface to be exposed to plasma, the surface having an arithmetic mean roughness Ra of 0.01 μm or more and 0.1 μm or less, the surface being provided with a plurality of pores, and a value obtained by subtracting an average equivalent circle diameter of the pores from an average distance between centroids of adjacent pores is 28 μm or more and 48 μm or less. A plasma processing device according to the disclosure includes the plasma processing device member described above.

An article according to an exemplary embodiment of this disclosure, among other possible things includes a substrate and a barrier layer on the substrate. The barrier layer includes a bond coat comprising a matrix, diffusive particles disposed in the matrix, and gettering particles disposed in the matrix. At least about 10% of the gettering particles are in a crystalline phase. The article also includes a top coat. An article is also disclosed.