Antifouling coating, raw antifouling slurry coating, antifouling coating system and method for applying the antifouling coating system

Abstract

Antifouling coating for a turbine component, the antifouling coating comprising: between 0.25 vol.% and 35 vol.% filler particles embedded in a chromium phosphate binder matrix, wherein the chromium phosphate binder matrix has a residue of the coating by volume, wherein the filler particles have a size in the range of nanosize to 6 micrometers with an aspect ratio of 1:1 to 3:1, wherein the filler particles contain: between 10 wt% and 90 wt% lubricating particles, wherein the lubricating particles are selected from the group consisting of boron nitride (BN), zinc (Zn), tin (Sn), zinc and tin oxides, and combinations thereof; and a remainder of hard particles, wherein the hard particles are selected from the group consisting of tungsten carbide (WC), silicon (Si), oxides or nitrides of silicon, and combinations thereof.

Description

FIELD OF THE INVENTION

[0001] The present invention is directed to a coating, a coating system, and a coating method. More specifically, the present invention is directed to an antifouling coating, an antifouling coating system, and a method for applying an antifouling coating. BACKGROUND TO THE INVENTION

[0002] During turbine operation, many components are exposed to high-temperature and high-pressure conditions. Furthermore, various airflow particles come into contact with the components as they flow through the turbine. Under these high-temperature and high-pressure conditions, the airflow particles can deposit on the surface of the components, particularly the compressor blades of an aft stage.

[0003] One method for reducing particulate deposition involves coating compressor blades with an inner layer of aluminum particles and an outer coating of ceramic alumina flakes. The outer coating of ceramic alumina flakes forms the outer surface of the component and provides some erosion protection. However, the airflow in a turbine often contains iron oxide particles, which can adhere to the ceramic alumina flakes on the surface of the compressor blades.

[0004] Another method for reducing particulate deposition involves the use of anti-stick compounds. Most currently used anti-stick compounds are limited to polytetrafluoroethylene (PTFE)-type materials, which have a temperature limit of 121°C (250°F). These anti-stick compounds are not suitable for use on aft stage compressor blades exposed to temperatures of 538°C (1000°F) or higher.

[0005] US 2003 / 0017355 A1 describes a coating for a gas turbine component comprising a mixture of a first type of particles in an amount of 60-90 vol.% and a second type of particles in an amount of 10-40 vol.% of the total, wherein the particles are dispersed in a liquid aqueous medium and have a nearly spherical geometry. The aqueous medium may contain chromium phosphate as a binder. The materials of the two particle types are selected from the group consisting of aluminum, chromium, zirconium, cobalt, nickel, iron, titanium, yttrium, gadolinium, their oxides, carbides, borides, or nitrides, as well as combinations thereof and alloys thereof.

[0006] An antifouling coating, a raw antifouling slurry coating and a coating system for a turbine component, and a coating method with improvements in the process and / or properties of the formed components would be desirable in the art. BRIEF DESCRIPTION OF THE INVENTION

[0007] The antifouling coating for a turbine component according to the invention contains between 0.25 vol.% and 35 vol.% filler particles embedded in a chromium phosphate binder matrix having a residue of the coating by volume. The filler particles range in size from nanosize to 6 micrometers with an aspect ratio of 1:1 to 3:1 and contain between 10 wt.% and 90 wt.% lubricating particles and a residue of hard particles. The lubricating particles are selected from the group consisting of boron nitride (BN), zinc (Zn), tin (Sn), zinc and tin oxides, and combinations thereof. The hard particles are selected from the group consisting of tungsten carbide (WC), silicon (Si), silicon oxides or nitrides, and combinations thereof.

[0008] In the antifouling coating mentioned above, the coating can have a thickness of about 15-75 micrometers.

[0009] Preferably, the coating may have a thickness of about 25-50 micrometers.

[0010] In the antifouling coating of any type mentioned above, the lubricious particles and the hard particles may have the same size range distribution.

[0011] Additionally or as an alternative, the coating may have a maximum service temperature of approximately 861°C (1582°F).

[0012] In any of the antifouling coatings mentioned above, the lubricating particles may contain boron nitride.

[0013] The raw ("green") antifouling slurry coating of the invention for producing the antifouling coating described above comprises an electroplated protective chromium phosphate binder, between 0.25% and 35% by volume of a powder mixture mixed with the binder, and a vaporizable solvent mixed with the powder mixture and the binder in a sufficient proportion so that the slurry has a viscosity that resists gravitational flow upon drying, wherein the vaporizable solvent and the binder comprise a residue of the raw antifouling slurry coating. The powder mixture contains filler particles ranging in size from nanometers to 6 micrometers with an aspect ratio of 1:1 to 3:1, wherein the filler particles contain between 10% and 90% by weight of lubricious particles and a residue of hard particles.The lubricating particles are selected from the group consisting of boron nitride (BN), zinc (Zn), tin (Sn), zinc and tin oxides, and combinations thereof. The hard particles are selected from the group consisting of tungsten carbide (WC), silicon (Si), silicon oxides or nitrides, and combinations thereof.

[0014] In the aforementioned raw antifouling slurry coating, the evaporable solvent may be an alcohol selected from the group of alcohols including CH3OH to C4H7OH.

[0015] The antifouling coating system for a turbine component according to the invention includes a turbine component, a turbine component, an alumina basecoat overlying the turbine component, the basecoat having a first predetermined thickness, and a topcoat comprising the antifouling coating described above.

[0016] In the antifouling coating system mentioned above, the topcoat may have a thickness of approximately 15-75 micrometers.

[0017] Preferably, the topcoat may have a thickness of about 25-50 micrometers.

[0018] In the antifouling coating system of any type mentioned above, the topcoat may have a maximum service temperature of about 861°C (1582°F).

[0019] Additionally or as an alternative, the turbine component may include compressor blades that experience a temperature of at least 482°C (900°F) during turbine operation.

[0020] In any antifouling coating system mentioned above, the base coating may further comprise aluminum-based particles in a phosphate matrix having a thickness of about 35-85 micrometers.

[0021] Additionally, or as an alternative, the final surface of the antifouling topcoat may have a centerline roughness (RA) of about 1.27 micrometers (50 microinches) or smoother.

[0022] The inventive method for applying the above-described antifouling coating system to a turbine component includes the steps of: providing a turbine component having an operating temperature below 861°C (1582°F); blast-cleaning a surface of the turbine component to create a surface finish sufficiently rough to support mechanical bonding of a coating layer; coating the blasted surface with a basecoat of aluminum particles in a phosphate matrix to a first preselected thickness; heat-treating the coated turbine component at a first preselected temperature for a first preselected period of time; curing the basecoat to the turbine component;Applying the above-described raw antifouling slurry coating over the basecoat to a second preselected thickness to produce the above-described antifouling coating; drying the raw antifouling slurry coating; heat-treating the antifouling coating applied over the coated turbine component at a second preselected temperature for a second preselected period of time; curing the antifouling coating to the basecoat; and optionally polishing the coated turbine component, thereby removing any high areas resulting from the application of the antifouling coating.

[0023] In one configuration of the aforementioned method, a composition of the raw antifouling slurry coating can be adjusted by adjusting the volume content of evaporable solvent such that the raw antifouling slurry coating is sufficiently fluid so that the raw antifouling slurry coating can be applied by spraying the turbine component with the raw antifouling slurry coating over the base coating.

[0024] Furthermore, the lubricious particles and the hard particles of the raw antifouling slurry coating may have the same size range distribution when the raw antifouling slurry coating is applied by spraying.

[0025] In a further configuration of the method, a composition of the raw antifouling slurry coating can be adjusted by adjusting the volume content of the evaporable solvent such that the raw antifouling slurry coating is sufficiently viscous so that the raw antifouling slurry coating can be applied over the base coating by immersing the turbine component in the raw antifouling slurry coating.

[0026] In any of the aforementioned methods, the step of heat treating the antifouling coating applied over the coated turbine component at a second preselected temperature for a second preselected time period may include heat treating the turbine component at a temperature of about 288-399°C (550-750°F) for a time period in the range of about 0.5-2 hours.

[0027] Further features and advantages of the present invention will become 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. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a cross-sectional view of an antifouling coating system according to an embodiment of the disclosure. Fig. 2 shows a flow diagram of a method for applying an antifouling coating according to an embodiment of the disclosure.

[0028] Wherever possible, the same reference numerals are used throughout the drawings to represent the same parts. DETAILED DESCRIPTION OF THE INVENTION

[0029] A coating, a coating system, and a coating method are provided. Compared to coatings, systems, and methods that do not employ one or more of the features disclosed herein, embodiments of the present disclosure reduce component fouling, increase efficiency, extend component life, reduce component downtime, reduce maintenance costs, provide a coating without compromising component performance, or provide a combination thereof.

[0030] In one embodiment, an antifouling coating contains, by volume, between about 0.25% and about 35% filler particles and a balance of ceramic matrix. In another embodiment, the antifouling coating contains, by volume, between 0.25% and 10% filler particles, between 0.25% and about 5% filler particles, between 0.25% and less than about 5% filler particles, or any combination, subcombination, range, or subrange thereof, with a balance of ceramic matrix. The filler particles include one or more lubricious particles and / or hard particles.For example, in another embodiment, the filler particles contain, by weight, between 10% and 90% lubricious particles, between 20% and 80% lubricious particles, between 30% and 70% lubricious particles, between 40% and 60% lubricious particles, 50% lubricious particles, or any combination, subcombination, range, or subrange thereof, with a remainder of hard particles. In another embodiment, the antifouling coating contains, in addition to the filler particles, binder additives such as, but not limited to, C, Ca, K, F, oxides or nitrides of C, Ca, K, F, or a combination of these. The ceramic matrix contains any suitable matrix for holding or embedding the filler particles, such as, but not limited to, a chromium phosphate binder matrix.

[0031] The lubricious and / or hard particles include, but are not limited to, metallic particles, ceramic particles, or a combination of these. Suitable lubricious particles include, but are not limited to, boron (B), titanium (Ti), zinc (Zn), tin (Sn), oxides and / or nitrides of B, Ti, Zn, and / or Sn, or a combination of these. For example, suitable lubricious particles may include boron nitride (BN), zinc oxide (ZnO), tin oxide (SnO), or a combination of these. Suitable hard particles include, but are not limited to, tungsten (W), silicon (Si), carbides, oxides and / or nitrides of W or Si, or a combination of these. For example, suitable hard particles may include tungsten carbide (WC), silicon oxide (SiO2), or a combination of these. Additional filler particles may include nickel oxide (NiO).

[0032] In one embodiment, the filler particles contain a particle shape and / or particle orientation that reduces porosity of the antifouling coating (i.e., increases density), reduces or eliminates gas and / or vapor permeability through the coating. Reducing or eliminating the permeability of the coating reduces or eliminates gas or vapor diffusion through the coating, reducing or eliminating any amount of gas and / or vapor reaching a substrate, particularly at elevated temperatures and / or pressures that might otherwise increase permeability. In another embodiment, the filler particles and / or binder additives increase the corrosion resistance of the coating, increase the oxidation resistance of the coating, increase the density of the coating, or provide a combination of these.

[0033] In a modified embodiment, the antifouling coating comprises a "green" (raw, unfinished) slurry coating. The raw slurry coating contains, by volume, between about 0.25% and about 35% of a powder mixture and a balance of a binder and a vaporizable solvent. The binder contains any suitable binder for holding the powder mixture, in any case a chromium phosphate electroplating protective binder. The powder mixture contains a mixture of the filler particles. In one embodiment, the powder mixture contains, by weight, 10-90% lubricious particles and a balance of the hard particles. The vaporizable solvent is mixed with the powder mixture and the binder in any proportion to provide a viscosity that resists gravitational flow of the coating upon drying.For example, in another embodiment, the evaporable solvent is blended into the antifouling coating to form a thixotropic mixture. Suitable evaporable solvents include, but are not limited to, alcohols, such as alcohols with between one and four carbon atoms (CH3OH to C4H7OH).

[0034] The lubricious particles and / or the hard particles in the antifouling coating have the same, similar, or dissimilar size range distributions. In one embodiment, the lubricious particles and / or the hard particles have a size in the range of nanosize to 6 micrometers with an aspect ratio of 1:1 to 3:1. Nanosize particles include particles having a size in the range between 1 and 100 nanometers. In another embodiment, the lubricious particles and / or the hard particles have a size in the range of nanosize to less than 3 micrometers, an average size of about 1 micrometer, an average size of less than about 1 micrometer, or any combination, subcombination, range, or subrange thereof.In another embodiment, the lubricating particles and / or the hard particles comprise any size smaller than that of larger foreign particles that come into contact with the coating, such as airflow particles (e.g., oxide particles) in a turbine. The smaller size of the lubricating particles and / or the hard particles reduces or eliminates the adhesion of the larger foreign particles to the coating.

[0035] Referring to Fig. 1, an antifouling coating system 100 includes a component 101, a basecoat 103, and a topcoat 105. In one embodiment, component 101 includes a turbine component, such as, but not limited to, a compressor blade, an aft stage compressor blade, another turbine component, or a combination thereof. In another embodiment, basecoat 103 includes an aluminum oxide layer overlying component 101, wherein basecoat 103 has a basecoat thickness 113. Basecoat thickness 113 is at least about 50 micrometers, between about 20 and about 100 micrometers, between about 35 and about 85 micrometers, between about 50 and about 75 micrometers, or any combination, subcombination, range, or subrange thereof.For example, a basecoat includes a 50 to 75 micrometer thick layer of aluminum-based particles in a phosphate matrix. In another embodiment, the topcoat 105 includes the antifouling coating overlying the basecoat 103, wherein the antifouling coating has an antifouling coating thickness 115. The antifouling coating thickness 115 is at least 15 micrometers, between about 15 and about 75 micrometers, between about 20 and about 60 micrometers, between about 25 and about 50 micrometers, or any combination, subcombination, range, or subrange thereof.

[0036] When applied as the topcoat 105, the antifouling coating provides a non-stick surface on an exterior surface of the component 101. The non-stick surface reduces or eliminates the adhesion of foreign particles, which reduces or eliminates fouling of the component 101 to which the coating is applied. Additionally, the antifouling coating and / or the basecoat 103 provide an oxidation protection barrier that reduces or eliminates oxidation of the component 101, such as during turbine operation, hot-pressing operations, or a combination thereof. The oxidation protection barrier is provided by the thickness and / or filler particles of the antifouling coating.In one embodiment, the antifouling coating is lubricated, provides a non-stick surface, and / or provides an anti-oxidation barrier at temperatures of up to about 861°C (1582°F), up to about 850°C (1562°F), between about 121°C (250°F) and about 871°C (1600°F), between about 121°C (250°F) and about 861°C (1582°F), between about 149°C (300°F) and about 850°C (1562°F), between about 149°C (300°F) and about 538°C (1000°F), or in any combination, subcombination, range, or subrange thereof. For example, in another embodiment, the antifouling coating is applied to compressor blades that experience a temperature of at least about 482°C (900°F) to provide the anti-stick surface and / or the oxidation protection barrier during turbine operation.In a further embodiment, the antifouling coating is inert to organic and / or corrosive agents, is not wetted by molten metal, molten glass and / or slag, or offers a combination of these.

[0037] Referring to the Fig. 1 and Fig.2, a method for applying the antifouling coating includes providing the component 101 (step 201), applying the basecoat 103 over the component 101 (step 203), and applying the topcoat 105 over the basecoat 103 (step 205). The antifouling coating is applied in-place, in the field to in-service components, to new components, or a combination thereof. As used herein, an in-service component refers to any component that has previously been manufactured and / or placed into service. In one embodiment, the component 101 includes a turbine component having an operating temperature of up to 850°C (1562°F). In another embodiment, the method includes preparing the component 101, such as by blasting a surface of the turbine component (step 202), prior to applying the basecoat 103 over the component 101.Blasting the surface creates a surface finish having a roughness that supports mechanical bonding of a coating (e.g., basecoat 103) to the surface. For example, blasting creates an average roughness (RA) of up to about 1.27 micrometers (50 microinches), up to about 0.762 micrometers (30 microinches), up to about 0.635 micrometers (25 microinches), up to about 0.508 micrometers (20 microinches), or any combination, subcombination, range, or subrange thereof. After blasting the surface (step 202), basecoat (103) is applied over component (101) (step 203), with basecoat 103 being applied to basecoat thickness 113.In another embodiment, the base coating 103 and the component 101 are subsequently heat-treated at a first preselected temperature for a first preselected time period (step 204). The heat treatment of the base coating 103 and the component 101 cures the base coating 103 to the component 101.

[0038] Next, the topcoat 105 is applied over the basecoat 103 (step 205), with the topcoat 105 including the antifouling coating applied to the antifouling coating thickness 115. In one embodiment, the antifouling coating includes the raw slurry coating. The raw slurry coating is applied over the basecoat 103 by any method, such as, but not limited to, spraying, dipping, or soaking the component in the raw slurry coating, polishing, dipping, and spinning, physical vapor deposition, or a combination thereof.The application of the raw slurry coating reduces or eliminates the use of high finishing technology, such as, but not limited to, vacuum application, expensive materials, elevated temperatures, or a combination of these, thereby reducing application costs.

[0039] Prior to applying the topcoat 105, the viscosity of the antifouling coating can be increased or decreased by decreasing or increasing the volume content of the evaporable solvent, respectively. In one example, the volume content of the evaporable solvent is adjusted to facilitate application of the raw slurry coating over the basecoat by immersing the component 101 into the raw slurry coating. In another example, the volume content of the evaporable solvent is increased to achieve a reduced viscosity that enables spraying of the raw slurry coating without gravitational flow of the topcoat 105 after application. In one embodiment, when the raw slurry coating is applied by spraying, the filler particles and the lubricious particles have the same or substantially the same size range distribution.

[0040] The antifouling coating is then dried and subsequently heat-treated at a second preselected temperature for a second preselected time period (step 206). Alternatively, the antifouling coating may be dried and heat-treated simultaneously. The heat treatment cures the antifouling coating to the base coating 103 to form a coated component. In another embodiment, the coated component is polished after the antifouling coating has cured. Polishing the coated component reduces or eliminates high areas created during application of the antifouling coating, reduces the surface roughness of the antifouling coating, or provides a combination of these.For example, polishing results in an antifouling coating centerline roughness (RA) of up to about 1.27 micrometers (50 microinches), up to about 0.635 micrometers (25 microinches), up to about 0.508 micrometers (20 microinches), up to about 0.382 micrometers (15 microinches), up to about 0.254 micrometers (10 microinches), or any combination, subcombination, range, or subrange of these.

[0041] The first preselected temperature and the second preselected temperature are the same, substantially the same, or different from each other. Suitable temperatures include, but are not limited to, up to about 399°C (750°F), between about 288°C (550°F) and about 399°C (750°F), between about 316°C (600°F) and 371°C (700°F), about 343°C (650°F), or any combination, subcombination, range, or subrange thereof. The first preselected time period and the second preselected time period are the same, substantially the same, or different from each other. Suitable time periods include, but are not limited to, up to about 3 hours, between about 0.5 and 3 hours, between about 0.5 and about 2 hours, or any combination, subcombination, range, or subrange thereof.

[0042] In one embodiment, when the antifouling coating is applied to the in-service component, the method includes removing an existing outer coating or the existing outer coating and at least a portion of an existing inner coating layer. For example, in another embodiment, the method of applying the antifouling coating includes removing an existing outer coating of ceramic alumina flakes and at least a portion of an inner layer of aluminum particles from the in-service component. The basecoat 103 and / or the antifouling coating are then applied over the in-service component according to the embodiments disclosed herein.

[0043] 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. Accordingly, 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.

[0044] A coating, coating system, and coating method are provided. The coating contains between about 0.25-35% filler particles embedded in a chromium phosphate binder matrix having a residue of the coating by volume. The filler particles range in size from nanosize to 6 micrometers with an aspect ratio of 1:1 to 3:1 and contain 10-90 wt.% lubricious particles with a residue of hard particles. The lubricious particles are selected from the group consisting of boron nitride (BN), zinc (Zn), tin (Sn), zinc and tin oxides, and combinations thereof. The hard particles are selected from the group consisting of tungsten carbide (WC), silicon (Si), silicon oxides or nitrides, and combinations thereof. A raw slurry coating contains a vaporizable solvent mixed with the filler particles and the chromium phosphate binder matrix.

Claims

[1] Antifouling coating for a turbine component, the antifouling coating comprising: between 0.25 vol.% and 35 vol.% filler particles embedded in a chromium phosphate binder matrix, wherein the chromium phosphate binder matrix has a residue of the coating by volume, wherein the filler particles have a size in the range of nanosize to 6 micrometers with an aspect ratio of 1:1 to 3:1, wherein the filler particles contain: between 10 wt% and 90 wt% lubricating particles, wherein the lubricating particles are selected from the group consisting of boron nitride (BN), zinc (Zn), tin (Sn), zinc and tin oxides, and combinations thereof; and a remainder of hard particles, wherein the hard particles are selected from the group consisting of tungsten carbide (WC), silicon (Si), oxides or nitrides of silicon, and combinations thereof. [2] The antifouling coating of claim 1, wherein the coating has a thickness of 15-75 micrometers; preferably, the coating has a thickness of 25-50 micrometers. [3] An antifouling coating according to claim 1 or 2, wherein the lubricating particles and the hard particles have the same size range distribution; and / or wherein the lubricating particles contain boron nitride. [4] An antifouling coating according to any one of the preceding claims, wherein the coating has a maximum service temperature of 861°C. [5] A raw antifouling slurry coating for producing the antifouling coating according to claim 1, comprising: a galvanic protective chromium phosphate binder; between 0.25 vol.% and 35 vol.% powder mixture, wherein the powder mixture is mixed with the binder and has filler particles with a size in the range from nanosize to 6 micrometers with an aspect ratio of 1:1 to 3:1, wherein the filler particles contain: between 10 wt% and 90 wt% lubricating particles, wherein the lubricating particles are selected from the group consisting of boron nitride (BN), zinc (Zn), tin (Sn), zinc and tin oxides, and combinations thereof; and a remainder of hard particles, wherein the hard particles are selected from the group consisting of tungsten carbide (WC), silicon (Si), oxides or nitrides of silicon, and combinations thereof; and a vaporizable solvent mixed with the powder mixture and the binder in a proportion sufficient for the slurry to have a viscosity that resists gravitational flow upon drying, the vaporizable solvent and the binder comprising a residue of the raw antifouling slurry coating. [6] The crude antifouling slurry coating according to claim 5, wherein the evaporable solvent is an alcohol selected from the group of alcohols including CH3OH to C4H7OH. [7] An antifouling coating system (100) for a turbine component, comprising: a turbine component (101); a base coating (103) of aluminum oxide covering the turbine component and having a first predetermined thickness (113); and a topcoat (105) comprising the antifouling coating (105) according to claim 1. [8] The antifouling coating system (100) of claim 7, wherein the topcoat (105) has a thickness of 15-75 micrometers; preferably, the topcoat (105) has a thickness of 25-50 micrometers. [9] The antifouling coating system (100) of claim 7 or 8, wherein the topcoat (105) has a maximum service temperature of 861°C; and / or wherein the turbine component (101) includes compressor blades that experience a temperature of at least 482°C during turbine operation. [10] The antifouling coating system (100) of any of claims 7-9, wherein the base coating (103) further comprises aluminum-based particles in a phosphate matrix having a thickness of 35-85 micrometers. [11] The antifouling coating system (100) of any of claims 7-10, wherein the surface finish of the antifouling topcoat (105) has a centerline roughness (RA) of 50 micrometers or smoother. [12] A method of applying the antifouling coating system according to claim 7 to a turbine component, comprising the steps of: Providing a turbine component (101) having an operating temperature below 861°C; blasting a surface of the turbine component (101) to produce a surface finish sufficiently rough to support mechanical bonding of a coating layer; Coating the blasted surface to a first preselected thickness (113) with a base coating (103) of aluminum particles in a phosphate matrix; Heat treating the coated turbine component (101) at a first preselected temperature for a first preselected period of time, whereby the base coating (103) is cured on the turbine component (101); applying the raw antifouling slurry coating of claim 5 over the base coating (103) to a second preselected thickness (115) to produce the antifouling coating of claim 1; Drying the raw antifouling slurry coating; heat treating the antifouling coating applied over the coated turbine component (101) at a second preselected temperature for a second preselected period of time, whereby the antifouling coating is cured to the base coating (103); and optionally polishing the coated turbine component (101) to remove any high areas resulting from the application of the antifouling coating. [13] The method of claim 12, wherein a composition of the raw antifouling slurry coating is adjusted by adjusting the volume content of the evaporable solvent such that the raw antifouling slurry coating is sufficiently fluid so that the raw antifouling slurry coating is applied over the base coating (103) by spraying the turbine component (101) with the raw antifouling slurry coating; wherein the lubricious particles and the hard particles of the raw antifouling slurry coating may have the same size range distribution when the raw antifouling slurry coating is applied by spraying. [14] The method of claim 12 or 13, wherein a composition of the raw antifouling slurry coating is adjusted by adjusting the volume content of the evaporable solvent such that the raw antifouling slurry coating is sufficiently viscous so that the raw antifouling slurry coating can be applied over the base coating (103) by immersing the turbine component (101) into the raw antifouling slurry coating. [15] The method of any of claims 12-14, wherein the step of heat treating the antifouling coating applied over the coated turbine component (101) at a second preselected temperature for a second preselected time period includes heat treating the turbine component (101) at a temperature of 288-399°C for a time period in the range of 0.5-2 hours.

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