A part includes a substrate having, adjacent to a surface of the substrate, at least a portion that is made of a material that contains silicon, and an environmental barrier formed on the surface of the substrate, the environmental barrier including a first layer including at least one first rare earth silicate and presenting grains with a mean size less than or equal to 1 μm; and a second layer covering the first layer, the second layer including at least one rare earth silicate and presenting grains with a mean size greater than 1 μm.

A part includes a substrate having, adjacent to a surface of the substrate, at least a portion that is made of a material that contains silicon, and an environmental barrier formed on the surface of the substrate, the environmental barrier including a first layer including at least one first rare earth silicate and presenting grains with a mean size less than or equal to 1 μm; and a second layer covering the first layer, the second layer including at least one rare earth silicate and presenting grains with a mean size greater than 1 μm.

A coating method includes depositing a slurry including a coarsely particulate ceramic and a finely particulate ceramic on a base material configured with an oxide-based ceramics matrix composite such that a proportion of coarse particles decreases towards a surface of the base material; forming a bond coating by performing a heat treatment on the base material on which the slurry has been deposited; and forming a top coating by thermally spraying a ceramic onto the bond coating. The oxide-based ceramics matrix composite is an alumina silica type oxide-based ceramics matrix composite. The coarsely particulate ceramic and the finely particulate ceramic are alumina-based powder.

A coating method includes depositing a slurry including a coarsely particulate ceramic and a finely particulate ceramic on a base material configured with an oxide-based ceramics matrix composite such that a proportion of coarse particles decreases towards a surface of the base material; forming a bond coating by performing a heat treatment on the base material on which the slurry has been deposited; and forming a top coating by thermally spraying a ceramic onto the bond coating. The oxide-based ceramics matrix composite is an alumina silica type oxide-based ceramics matrix composite. The coarsely particulate ceramic and the finely particulate ceramic are alumina-based powder.

A multilayer 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 deposited directly on the substrate, and a plurality of pairs of alternating layers of the rare earth disilicate material and a rare earth monosilicate material deposited and sintered directly on the environmental barrier coating layer. Each layer of the plurality of pairs of alternating layers is relative less thick as compared with the environmental barrier coating layer.

A multilayer 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 deposited directly on the substrate, and a plurality of pairs of alternating layers of the rare earth disilicate material and a rare earth monosilicate material deposited and sintered directly on the environmental barrier coating layer. Each layer of the plurality of pairs of alternating layers is relative less thick as compared with the environmental barrier coating layer.

The present application provides a high-wear-resistance far-infrared ceramic polished glazed tile and preparation method therefor. The preparation method includes application of far-infrared overglaze, ink-jet printing, application of transparent far-infrared polished glaze and application of abrasion-resistant far-infrared polished glaze in sequence on a body, firing, and polishing. By adopting the far-infrared overglaze, the transparent far-infrared polished glaze and the abrasion-resistant far-infrared polished glaze in combination, the polished glaze tile can have a far-infrared function, high transparency, and high abrasion resistance.

The present application provides a high-wear-resistance far-infrared ceramic polished glazed tile and preparation method therefor. The preparation method includes application of far-infrared overglaze, ink-jet printing, application of transparent far-infrared polished glaze and application of abrasion-resistant far-infrared polished glaze in sequence on a body, firing, and polishing. By adopting the far-infrared overglaze, the transparent far-infrared polished glaze and the abrasion-resistant far-infrared polished glaze in combination, the polished glaze tile can have a far-infrared function, high transparency, and high abrasion resistance.

A method for coating a substrate includes spraying a combination of powders. The combination of powders includes: Hf.sub.0.5Si.sub.0.5O.sub.2; Zr.sub.0.5Si.sub.0.5O.sub.2; and, optionally, at least one of HfO.sub.2 and ZrO.sub.2. A molar ratio of said Hf.sub.0.5Si.sub.0.5O.sub.2 and HfO.sub.2 combined to said Zr.sub.0.5Si.sub.0.5O.sub.2 and ZrO.sub.2 combined is from 2:1 to 4:1. A molar ratio of said Hf.sub.0.5Si.sub.0.5O.sub.2 to said HfO.sub.2 is at least 1:3.

The invention discloses micron-nano pore gradient oxide ceramic films with biological activity, which are prepared by the following methods: The surface structures are biomedical engineering materials; Inorganic precursor coating solutions or the organic precursor coating solutions are prepared with or without micron and nanopore additives; The surface structures of the substrate are treated in the following steps: (1) The surfaces of the substrate are coated by the inorganic precursor coating solutions or the organic precursor coating solutions with or without micron and nanopore additives; (2) The substrate with coatings are dried, sintered, naturally cooled, and cleaned. (3) The biomedical engineering materials with the micron-nanopore gradient oxide ceramic films, especially biomimetic micro-nanoporous gradient alumina film, yttrium partially stabilized zirconia film, and alumina doped yttrium partially stabilized zirconia films in this invention greatly improve biocompatibility and biological activity.