A diffusion barrier coating on a nickel-based alloy substrate comprising the diffusion barrier being coupled to the substrate between the substrate and a composite material opposite the substrate, wherein the diffusion barrier comprises a nickel phosphorus alloy material.

A method of fabricating an abradable coating of varying density, and an abradable coating of varying density. The method comprises the following steps: providing a substrate having a first portion and a second portion; depositing a first precursor material on the first portion of the substrate; compressing the first precursor material between the substrate and a first bearing surface; sintering the first precursor material as compressed in this way in order to obtain a first abradable coating portion on the first portion of the substrate, and possessing a first density; depositing a second precursor material on the second portion of the substrate; and compressing the second precursor material between the substrate and a second bearing surface.

Disclosed herein is an article comprising a substrate; an abrasive coating disposed on the substrate; where the abrasive coating comprises a matrix having abrasive grit particles dispersed therein; and a layer of material disposed on the abrasive coating; where the layer of material is a titanium nitride (TiN), boron nitride (BN), titanium-aluminum-nitrides [(TiAl)N], titanium-aluminum-silicon-nitrides [(TiAlSi)N], chromium nitrides (CrN), aluminum oxide (Al.sub.2O.sub.3), titanium oxide (TiO.sub.2), silicon carbo-nitride (SiCN), titanium carbo-nitride (TiCN), or a combination thereof.

Provided are a coating structure, a turbine part having the same, and a method for manufacturing the coating structure. The coating structure is provided on a surface of a base portion including a ceramic matrix composite. The coating structure is layered on the surface of the base portion, and includes a bond coat layer formed of a rare-earth silicate and a top coat layer layered on the bond coat layer. The residual stress present in the bond coat layer is compressive residual stress. The oxygen permeability coefficient of the bond coat layer is no greater than 10.sup.−9 kg.Math.m.sup.−1.Math.s.sup.−1 at a temperature of not lower than 1200° C. and a higher oxygen partial pressure of not less than 0.02 MPa. The bond coat layer may contain carbonitride particles or carbonitride whiskers.

A turbomachine includes a shroud and a rotor, which includes first and second blades. A first blade tip and a second blade tip respectively include a base and a first layer. The second blade tip also includes an abrasive second layer layered over the respective first layer. The first layer has a lower material hardness than the shroud. The second layer has a lower thermal stability than the shroud and the first layer. The rotor performs a grind operation and, subsequently, a post-grind operation. The second layer, in the grind operation, contacts and removes material from the shroud, and wears away, thereby revealing the first layer of the second blade tip for the post-grind operation. The first layer of the first blade tip is spaced apart with at least some radial clearance from the shroud in the grind and post-grind operations.

An article includes a ceramic-based substrate and a barrier layer on the ceramic-based substrate. The barrier layer includes a matrix phase and a network of gettering particles in the matrix phase. The gettering particles have an average maximum dimension between about 30 and 70 microns. The gettering particles have maximum dimensions that range from about 1 to 100 microns, and a dispersion of barium-magnesium alumino-silicate particles in the matrix phase. A composite material and a method of applying a barrier layer to a substrate are also disclosed.

In a non-limiting example, an article having a body including a nickel-based superalloy is provided. The nickel-based superalloy has a microstructure that includes a gamma phase matrix and a gamma prime phase including a plurality of rafting-resistant gamma prime particles dispersed in the gamma phase matrix. The plurality of the rafting-resistant gamma prime particles has an average particle perimeter of about 3 microns to about 15 microns, an average aspect ratio of about 1.2 to about 3, and where the microstructure of the nickel-based superalloy is substantially uniform throughout the body.

There is provided a method of treating a nickel base super alloy (NiSa) article. First, the NiSa article having fine grains is obtained. The NiSa article has a uniform distribution of the fine grains and substantially uniform mechanical properties throughout. One or more regions within the NiSa article are mechanically deformed. Then, the NiSa article is heat treated to obtain coarse grains in the one or more regions, the coarse grains having a size that is larger than that of the fine grains of the NiSa article outside of the one or more regions.

In a non-limiting example, an article having a body including a nickel-based superalloy is provided. The nickel-based superalloy has a microstructure that includes a gamma phase matrix and a gamma prime phase including a plurality of rafting-resistant gamma prime particles dispersed in the gamma phase matrix. The plurality of the rafting-resistant gamma prime particles has an average particle perimeter of about 3 microns to about 15 microns, an average aspect ratio of about 1.2 to about 3, and where the microstructure of the nickel-based superalloy is substantially uniform throughout the body.

A diffusion barrier coating on a nickel-based alloy substrate comprising the diffusion barrier being coupled to the substrate between the substrate and a composite material opposite the substrate, wherein the diffusion barrier comprises a nickel phosphorus alloy material.