Abstract:
A coated seal slot system for turbomachinery includes a first turbine component comprising a first groove having at least one first coating attached to at least a portion of the first groove of the first turbine component, a second turbine component comprising a second groove having at least one second coating attached to at least a portion of the second groove of the second turbine component. The first and the second turbine components are disposable adjacent to each other with the first groove having the first coating and the second groove having the second coating together forming a coated seal slot extending across a gap between the first turbine component and the second turbine component. A seal is disposable in the coated seal slot and extendable across the gap between the first and the second turbine components and engageable with the first coating and the second coating to inhibit leakage of gas through the gap.
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:
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:
A stacked up structure can include a first environmental barrier coating (EBC) layer and a second EBC layer. A first process can be used to form the first layer and a second process can be used to form the second layer. In one embodiment interfacial material can be formed for improved bonding of the second layer to the first layer. The interfacial material can define a continuous or discontinuous layer of nonuniform thickness.
Abstract:
A rare earth silicate-based hermetic layer includes a thermal sprayed coating including a rare earth silicate having a hermetic microstructure. An environmental barrier coating includes a bond coat layer including silicon; and at least one rare earth silicate-based hermetic layer deposited on the bond coat layer by thermal spraying. The rare earth silicate-based hermetic layer includes a thermal sprayed coating including a rare earth silicate having a hermetic microstructure. An article for service in extreme environments may be provided with such an environmental barrier coating. A thermal spray feedstock for producing a rare earth silicate-based hermetic layer.
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.