Abstract: Provided is a nickel-based coating composition containing cobalt, chromium, aluminum, tantalum, and nickel. The coating composition has a three phase ?, ??, ? microstructure wherein at least 5 volume % of the coating composition is present in the ? phase. Also provided are coating systems containing the coating composition, articles having the coating composition or coating system, and methods for protecting nickel-based superalloy substrates using the coating composition or coating system.

Abstract: Methods of forming an environmental barrier coating are disclosed. A method includes disposing a powder-based coating on a substrate, heat-treating the powder-based coating at a temperature greater than 800° C. and less than 1200° C. to form a porous coating that includes surface-connected pores, infiltrating at least some of the surface-connected pores of the porous coating with an infiltrant material to form an infiltrated coating, and sintering the infiltrated coating at a temperature greater than 1200° C. and less than 1500° C. to form the environmental barrier coating on the substrate.

Abstract: The disclosure provides for an article including a substrate, an environmental barrier coating (EBC), a bondcoat and a boron source. The substrate may include a silicon-including ceramic material. The EBC may be disposed over the substrate, and the bondcoat may disposed between the substrate and the EBC. The bondcoat may include silicon. The boron source may be disposed within the article to provide an effective amount of boron to form an oxide including silicon and at least 0.1 weight percent boron during exposure of the bondcoat to an oxidizing environment at a temperature greater than 900 degrees Celsius. The oxide may be a borosilicate glass that is substantially devitrification resistant to prevent spallation of the EBC and thereby enhance the temperature capability of the article.

Abstract: An article includes a silicon-containing region; at least one outer layer overlying a surface of the silicon-containing region; and a constituent layer on the surface of the silicon-containing region and between and contacting the silicon-containing region and the at least one outer layer, the constituent layer being formed by constituents of the silicon-containing region and being susceptible to creep within an operating environment of the article, wherein the silicon-containing region defines a plurality of channels and a plurality of ridges that interlock within the plurality of channels are formed in the silicon-containing region to physically interlock the at least one outer layer with the silicon-containing region through the constituent layer.

Abstract: There is set forth herein a silicon-based patch formulation comprising about 25 to 66 percent by volume of a solvent; about 4 to 10 percent by volume of a silicon-comprising binding material; and about 30 to 65 percent by volume of a patching material, the patching material comprising particles having one or more non-actinide Group IIIA elements, wherein a molar ratio of the one or more non-actinide Group IIIA elements to silicon within the patch formulation is about 0.95 to 1.25.

Abstract: A bond layer may be applied to the substrate of an article and a first layer may be applied to the bond layer by thermal spray. A second layer may be applied above the first layer by slurry coating.

Abstract: An article includes a silicon-containing region including surface features on a surface thereof. The surface features include depressions, protuberances, or combinations thereof. At least one outer layer overlies the surface of the silicon-containing region. A constituent layer is provided on the surface of the silicon-containing region and between and contacting the silicon-containing region and the at least one outer layer. The constituent layer is formed by constituents of the silicon-containing region and is susceptible to creep within an operating environment of the article. The surface features physically interlock the at least one outer layer with the silicon-containing region through the constituent layer.

Abstract: Systems and methods for recovery of rare-earth constituents from environmental barrier coatings (EBCs) are provided. One method includes for separating rare-earth (RE) containing constituents from a particulate feedstock containing a mixture of RE silicates and non-magnetic constituents includes disposing a collection member in a vicinity of the feedstock and magnetizing the collection member to generate a magnetic field sufficient to selectively attract the RE silicates to the collection member. The method further includes removing the RE silicates from the collection member.

Abstract: There is set forth herein a silicon-based patch formulation comprising about 25 to 66 percent by volume of a solvent; about 4 to 10 percent by volume of a silicon-comprising binding material; and about 30 to 65 percent by volume of a patching material, the patching material comprising particles having one or more non-actinide Group IIIA elements, wherein a molar ratio of the one or more non-actinide Group IIIA elements to silicon within the patch formulation is about 0.95 to 1.25.

Abstract: In one example of the present technology, a method for forming an article includes disposing an electrically conductive coating on a substrate. The method further includes disposing a layer stack on the electrically conductive coating by (i) disposing a first barrier coating by electrophoretic deposition; (ii) heat treating the first barrier coating; (iii) disposing an electrically conductive layer on the first barrier coating; and (iv) optionally repeating steps (i) to (iii). The method further includes disposing a second barrier coating on an outermost electrically conductive layer in the layer stack by electrophoretic deposition; and heat treating the second barrier coating.

Abstract: Systems and methods for recovery of rare-earth constituents from environmental barrier coatings are provided. One method includes extracting rare-earth (RE) oxide constituents from a feedstock containing RE silicates and non-RE contaminants. The method includes leaching the REs from the feedstock into an acid to form an acid solution, performing an oxalate precipitation on the acid solution to form an RE oxalate hydrate, and separating the RE oxalate hydrate from the acid solution. The method also includes heat treating the RE oxalate hydrate to form an RE oxide containing the RE elements extracted from the feedstock.

Abstract: A manufacturing method includes forming one or more grooves in a component that comprises a substrate with an outer surface. The substrate has at least one interior space. Each groove extends at least partially along the substrate and has a base and a top. The manufacturing method further includes applying a structural coating on at least a portion of the substrate and processing at least a portion of the surface of the structural coating so as to plastically deform the structural coating at least in the vicinity of the top of a respective groove, such that a gap across the top of the groove is reduced. A component is also disclosed and includes a structural coating disposed on at least a portion of a substrate, where the surface of the structural coating is faceted in the vicinity of the respective groove.

Abstract: A manufacturing method includes forming one or more grooves in a component that comprises a substrate with an outer surface. The substrate has at least one interior space. Each groove extends at least partially along the substrate and has a base and a top. The manufacturing method further includes applying a structural coating on at least a portion of the substrate and processing at least a portion of the surface of the structural coating so as to plastically deform the structural coating at least in the vicinity of the top of a respective groove, such that a gap across the top of the groove is reduced. A component is also disclosed and includes a structural coating disposed on at least a portion of a substrate, where the surface of the structural coating is faceted in the vicinity of the respective groove.

Abstract: Methods of manufacturing turbine shrouds with an abradable coating that balance the apparently contradictory requirements of high flowpath solidity, low blade tip wear, and good durability in service. The methods include obtaining a shroud substrate. The methods may include obtaining a coating system on the shroud substrate. The methods include forming an abradable coating on a surface of the coating system so as to form a substantially smooth flowpath surface. Forming the abradable coating includes forming a relatively dense scaffold and relatively porous filler regions in-between the relatively dense abradable scaffold. The methods may also include machining the abradable so as to achieve a substantially smooth flowpath surface comprising a relatively porous abradable phase surrounded by a relatively dense, high-durability corrale phase.

Abstract: Turbine shroud abradable coatings that balance the apparently contradictory requirements of high flowpath solidity, low blade tip wear, and good durability in service. The shrouds include a shroud substrate, a coating system, and an abradable coating. The coating system overlies at least a portion of an outer surface of the shroud substrate. The coating system includes a bond coat, a thermal barrier coating (TBC), and/or an environmental barrier coating (EBC). The abradable coating overlies at least a portion of the barrier coating. The abradable coating defines a substantially smooth continuous flowpath surface. The abradable coating includes a hybrid microstructure including a relatively dense, high-durability phase corralling relatively porous abradable phases. The second phases are relatively more abradable by the blades of a turbine than the second regions.

Abstract: Systems and methods for recovery of rare-earth constituents from environmental barrier coatings (EBCs) are provided. One method includes for separating rare-earth (RE) containing constituents from a particulate feedstock containing a mixture of RE silicates and non-magnetic constituents includes disposing a collection member in a vicinity of the feedstock and magnetizing the collection member to generate a magnetic field sufficient to selectively attract the RE silicates to the collection member. The method further includes removing the RE silicates from the collection member.

Abstract: An environmentally resistant patch includes one or more rare earth silicates, wherein an inorganic composition of the environmentally resistant patch includes, once cured, from about 80 mole percent to about 100 mole percent of a rare earth monosilicate and/or rare earth disilicate composition and from about 0 mole percent to about 20 mole percent of an inorganic additive, and, wherein the environmentally resistant patch has, once cured, an adhesive strength of at least about 3 MPa and a coefficient of thermal expansion of from about 3.5×10?6/° C. to about 7.5×10?6/° C.

Abstract: A turbine component patch delivery system can include a support arm and a deposition tool supported by the support arm. The deposition tool can include a reservoir configured to house a turbine component patch material and a dispenser configured to dispense the turbine component patch material from the reservoir onto a surface of a turbine component.

Abstract: Systems and methods for recovery of rare-earth constituents from environmental barrier coatings are provided. One method includes extracting rare-earth (RE) oxide constituents from a feedstock containing RE silicates and non-RE contaminants. The method includes leaching the REs from the feedstock into an acid to form an acid solution, performing an oxalate precipitation on the acid solution to form an RE oxalate hydrate, and separating the RE oxalate hydrate from the acid solution. The method also includes heat treating the RE oxalate hydrate to form an RE oxide containing the RE elements extracted from the feedstock.

Abstract: A turbine component patch delivery system can include a compressed gas source fluidly connected to a delivery line comprising a dispensing end. The turbine component patch delivery system can further include one or more turbine component patch carriers that can be projected out of the dispensing end of the delivery line by the compressed gas source, wherein each of the one or more turbine component patch carriers comprise a turbine component patch material housed within a breakaway shell.