The present invention is generally directed to a coated ceramic matrix composite or metallic component for a gas turbine and a method of forming a coated ceramic matrix composite or metallic component for a gas turbine. More specifically, the present invention is directed to a coated ceramic matrix composite or metallic component comprising an angled or rounded feature and a method of forming a coated ceramic matrix composite or metallic component comprising an angled or rounded feature.
Certain components, such as components for a gas turbine, operate at high temperatures and pressures. In particular, hot gas flow travels across turbine components at an angle. The surface of turbine components experiencing direct or indirect impingement of hot gas flow may be subject to erosion of the coating from the flow. Known hot gas path components have sharp edged features that result in undesirable hot gas flow impingement. In addition, the sharp edged features result in difficulties forming suitable coatings.
In an exemplary embodiment, a coated ceramic matrix composite or metallic component for a gas turbine is provided. The component comprises a substrate comprising a first surface and a hot gas path surface. The hot gas path surface is arranged and disposed to contact a hot gas flow when the component is installed in the gas turbine. The first surface is disposed at an angle to the hot gas path surface and opposes at least one adjacent component when the component is installed in the gas turbine. The component further comprises an angled or rounded feature extending from the first surface to the hot gas path surface. The component further comprises an environmental barrier coating or thermal barrier coating on at least a portion of the hot gas path surface. The angled or rounded feature reduces an incidence angle of the hot gas flow onto the first surface.
In another exemplary embodiment, a gas turbine assembly comprising a plurality of a coated ceramic matrix composite component is provided. The component comprises a substrate comprising a first surface and a hot gas path surface. The hot gas path surface is arranged and disposed to contact a hot gas flow when the component is installed in the gas turbine. The first surface is disposed at an angle to the hot gas path surface and opposes at least one adjacent component when the component is installed in the gas turbine. The component further comprises an angled or rounded feature extending from the first surface to the hot gas path surface. The component further comprises an environmental barrier coating or thermal barrier coating on at least a portion of the hot gas path surface. The angled or rounded feature reduces an incidence angle of the hot gas flow onto the first surface.
In another exemplary embodiment, a method for forming a coated ceramic matrix composite or metallic component is provided. The method comprises a step of providing a component having a substrate comprising a first surface and a hot gas path surface. The method further comprises a step of forming an angled or rounded feature extending from the first surface to the hot gas path surface. The method further comprises a step of forming an environmental barrier coating or thermal barrier coating on at least a portion of the hot gas path surface. The hot gas path surface is arranged and disposed to contact a hot gas flow when the component is installed in the gas turbine. The first surface is disposed at an angle to the hot gas path surface and opposes at least one adjacent component when the component is installed in the gas turbine. The angled or rounded feature reduces an incidence angle of the hot gas flow onto the first surface.
Other features and advantages of the present invention will be apparent from the following more detailed description of the preferred embodiment, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.
Wherever possible, the same reference numbers will be used throughout the drawings to represent the same parts.
Provided are exemplary methods and coated ceramic matrix composite or metallic components. Embodiments of the present disclosure, in comparison to methods and coated ceramic matrix composite or metallic components not utilizing one or more features disclosed herein, provide an environmental barrier coating or thermal barrier coating to the first side of the components and prevent erosion of the coating, thereby prolong the part life.
With reference to
In one embodiment, substrate 201 comprises a ceramic matrix composite material selected from the group consisting of carbon-fiber-reinforced silicon carbide (C/SiC), silicon-carbide-fiber-reinforced silicon carbide (SiC/SiC), carbon-fiber-reinforced silicon nitride (C/Si3N4), silicon nitride-silicon carbide composite (Si3N4/SiC), alumina-fiber-reinforced alumina (Al2O3/Al2O3), and combinations thereof.
In one embodiment, substrate 201 comprises a metallic component. The metallic component may include, but not be limited to, stainless steels, titanium superalloy, cobalt superalloy and nickel superalloy.
In one embodiment, coating 202 comprises a bond coat and a top coat. In another embodiment, coating 202 consists of a bond coat and a top coat. In another embodiment, coating 202 comprises a bond coat and multiple top coats. In another embodiment, coating 202 consists of a bond coat and multiple top coats. In another embodiment, coating 202 comprises multiple bond coats and a top coat. In another embodiment, coating 202 consists of multiple bond coats and a top coat. In another embodiment, coating 202 comprises multiple bond coats and multiple top coats. In another embodiment, coating 202 consists of multiple bond coats and multiple top coats. In another embodiment, coating 202 comprises at least one bond coat, at least one thermally grown oxide layer and at least one top coat. In another embodiment, coating 202 consists of at least one bond coat, at least one thermally grown oxide layer and at least one top coat.
In one embodiment, suitable bond coat comprises a material selected from the group consisting of silicon, silicon-based alloy, silicon-based composite, silicon dioxide, MCrAlY and combinations thereof wherein M is Ni, Co, Fe, or mixtures thereof. A person skilled in the art will appreciate that any suitable bond coat materials are envisaged.
In one embodiment, coating 202 further comprises a transition layer comprising a material selected from the group consisting of barium strontium alumino silicate (BSAS), mullite, yttria-stabilized zirconia, (Yb,Y)2Si2O7, rare earth monosilicates and disilicates and combinations thereof. A person skilled in the art will appreciate that any suitable TBC or EBC materials are envisaged.
In one embodiment, suitable top coat comprises a material selected from the group consisting of Y2SiO5, barium strontium alumino silicate (BSAS), yttria-stabilized zirconia, yttria-stabilized hafnia, yttria-stabilized zirconia with additions of one or more rare earth oxides, yttria-stabilized hafnia with additions of one or more rare earth oxides and combinations thereof. A person skilled in the art will appreciate that any suitable top coat materials are envisaged.
In one embodiment, coated ceramic matrix composite or metallic component 100 may include shrouds, nozzles, blades, combustors, combustor transition pieces, combustor liners, combustor tiles and combinations thereof. A person skilled in the art will appreciate that any suitable coated ceramic matrix composite or metallic components are envisaged.
With reference to
With reference to
In one embodiment, intersegment gap 504 is between about 0.05 and about 0.1 inches, between about 0.06 and about 0.09 inches, or between about 0.07 and about 0.08 inches, including increments, intervals, and sub-range therein, in the hot operating condition or at steady state operation.
In one embodiment, hot gas flow 103 is naturally directed at a deflection angle 505 in a downward direction and directed toward angled or rounded feature 104 as it passes intersegment gap 504 due to gas density, gas speed and gas pressure. In one embodiment, hot gas flow 103 is directed 7-9° in a downward direction and directed toward angled or rounded feature 104 as it passes intersegment gap 504. In another embodiment, hot gas flow 103 is directed 5°-15°, 6°-14°, 7°-13°, 8°-12°, or 9°-11°, including increments, intervals, and sub-range therein, in a downward direction and directed toward angled or rounded feature 104 as it passes an intersegment gap 504.
In one embodiment, second surface 501 of an opposing or adjacent component is defined to be a surface opposing to first surface 101, wherein first surface 101 and second surface 501 face each other.
In one embodiment, second surface 501 does not include an angled or rounded feature. In another embodiment, second surface 501 includes an angled or rounded feature.
With reference to
With reference to
In one embodiment, the step of forming the angled or rounded feature (step 802) may include a process selected from casting, layup, machining, grinding, laser ablation, waterjet, and combinations thereof. In one embodiment, the step of forming coating 202 (step 803) comprises at least one of physical vapor deposition, chemical vapor deposition, plasma-enhanced chemical vapor deposition, air plasma spray, vacuum plasma spray, combustion spraying with powder or rod, slurry coating, sol gel, dip coating, electrophoretic deposition, tape casting, and additive manufacturing techniques.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.