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:
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:
A coating system on a CMC substrate is provided, along with methods of its tape deposition onto a substrate. The coating system can include a bond coat on a surface of the CMC substrate; a first rare earth silicate coating on the bond coat; a first sacrificial coating of a first reinforced rare earth silicate matrix on the at least one rare earth silicate layer; a second rare earth silicate coating on the sacrificial coating; a second sacrificial coating of a second reinforced rare earth silicate matrix on the second rare earth silicate coating; a third rare earth silicate coating on the second sacrificial coating; and an outer layer on the third rare earth silicate coating. The first sacrificial coating and the second sacrificial coating have, independently, a thickness of about 4 mils to about 40 mils.
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:
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.