Anti-oxidation coating and preparation method thereof, high-temperature component and aviation equipment

Abstract

The invention provides an anti-oxidation coating, a preparation method thereof, a high-temperature component and aviation equipment, and relates to the technical field of coatings. The anti-oxidation coating comprises a first coating and a second coating which are sequentially stacked; the first coating comprises one or more of an MCrAlY layer, an Ni-Al layer and a Pt-Al layer, and M comprises Co or / and Ni; and the second coating comprises a nano Al-Al2O3 layer. The anti-oxidation coating provided by the invention has excellent anti-oxidation performance and short oxidation desorption time, so that the service life of the anti-oxidation coating can be effectively prolonged, and the risk of failure of the anti-oxidation coating is reduced.

Description

Technical Field

[0001] The present application relates to the field of coating technology, and in particular to an anti-oxidation coating and a preparation method thereof, high-temperature components and aviation equipment. Background Art

[0002] With the development of aviation equipment such as aircraft engines and gas turbines, high-temperature components face serious oxidation problems during production and operation.

[0003] In order to solve this problem, researchers have improved the oxidation resistance of the substrate by setting aluminide coatings such as MCrAlY coating, Ni-Al coating or Pt-Al coating. The anti-oxidation principle of these coatings is to form dense Al at high temperature. 2 O 3 However, when these coatings are in service at temperatures above 1100°C, they are prone to peeling due to wrinkles and thermal stress mismatch caused by excessive growth of TGO, and their oxidation resistance is greatly weakened.

[0004] In recent years, magnetron sputtering technology has made significant progress in the field of material preparation, especially in the preparation of coatings. Magnetron sputtering is a process that uses a magnetic field to control the movement of sputtered particles. It has the characteristics of high sputtering rate, good deposition uniformity and low energy consumption. However, the traditional magnetron sputtering process is usually carried out in a high vacuum environment to reduce the influence of oxygen on the deposited coating.

[0005] Therefore, it is of great significance to develop a new type of anti-oxidation coating. Summary of the invention

[0006] The purpose of the present application is to provide an anti-oxidation coating and a preparation method thereof, a high-temperature component and aviation equipment to solve the above-mentioned problems.

[0007] To achieve the above objectives, the present application provides, in a first aspect, an anti-oxidation coating, comprising a first coating and a second coating stacked in sequence; The first coating layer comprises one or more of an MCrAlY layer, a Ni-Al layer, and a Pt-Al layer, wherein M comprises Co and / or Ni; The second coating includes nano Al-Al 2 O 3 layer.

[0008] Optionally, the anti-oxidation coating satisfies at least one of the following conditions: A. The thickness of the first coating is 30 μm-200 μm; B. The thickness of the second coating layer is 200nm-1000nm.

[0009] Optionally, the nano Al-Al 2 O 3 Al and Al in the layer 2 O 3 The molar ratio is 1:0.9-1.5.

[0010] The second aspect of the present application provides a method for preparing the anti-oxidation coating, comprising: A first coating is provided on the surface of the substrate by using a thermal spraying method or / and an aluminizing method; Under a vacuum environment, magnetron sputtering is performed on the surface of the first coating to form a second coating to obtain an anti-oxidation coating.

[0011] Optionally, the vacuum degree of the vacuum environment is 2×10 -1 Pa-9.3×10 -2 Pa.

[0012] Optionally, the method for preparing the anti-oxidation coating satisfies at least one of the following conditions: A. the temperature of the substrate and the first coating during the magnetron sputtering is 350° C.-550° C.; B. The carrier gas flow rates of argon and nitrogen during the magnetron sputtering process are independently 150 mL / min-600 mL / min; C. The bias voltage during the magnetron sputtering process is 200V-800V; D. The duty cycle during the magnetron sputtering process is 15%-45%.

[0013] Optionally, the method further includes cooling the substrate, the first coating and the second coating after the magnetron sputtering, and performing a pre-oxidation treatment in an atmospheric environment.

[0014] Optionally, the pre-oxidation treatment is carried out at a temperature of 750°C-900°C and for a time of 2h-8h.

[0015] A third aspect of the present application provides a high-temperature component, comprising a substrate and an anti-oxidation coating disposed on the surface of the substrate; The anti-oxidation coating includes the anti-oxidation coating or the anti-oxidation coating prepared by the preparation method of the anti-oxidation coating; The substrate includes a nickel-based high-temperature alloy and / or a single crystal high-temperature alloy.

[0016] A fourth aspect of the present application provides an aviation equipment, comprising the above-mentioned high-temperature component.

[0017] Compared with the prior art, the beneficial effects of this application include: The anti-oxidation coating provided in the present application is provided with a layer of Al / Al on the surface of the first coating such as the MCrAlY anti-oxidation layer and / or the aluminide anti-oxidation layer. 2 O 3 Nanolayer, Al / Al 2 O 3 The nanolayer can quickly break away from the competitive oxidation stage at the initial stage of high temperature (above 900°C), reduce the accumulation of oxides, thus shortening the oxidation desorption time, and finally form an ordered crystal of aluminum oxide. This ordered aluminum oxide layer can effectively inhibit further oxidation, thereby improving the antioxidant performance of the coating; the formation of aluminum oxide crystals is divided into the nucleation stage and the growth stage, Al / Al 2 O 3 The second nano-coating is a dense and ordered α-Al 2 O 3 Provide nucleation, so that it skips the nucleation stage during formation and directly enters the growth stage, so that the crystal can be quickly ordered; and, due to the deposition of the second coating, it is α-Al 2 O 3 Provides nucleation, thus directly entering into the α-Al 2 O 3 During the growth stage, other oxides hardly appear; the antioxidant coating provided by the present application has excellent antioxidant properties and fast oxide film densification time, which can effectively extend the service life of the antioxidant coating and reduce the risk of failure of the antioxidant coating.

[0018] The preparation method of the anti-oxidation coating provided in the present application realizes the surface activation of the anti-oxidation coating through magnetron sputtering treatment. This method can not only improve the anti-oxidation performance of the coating, but also has the advantages of lower energy consumption and better deposition uniformity, thus providing a new solution for the anti-oxidation treatment of high-temperature components.

[0019] The high-temperature components provided in the present application have strong anti-oxidation ability and can extend the service life in a high-temperature environment.

[0020] The aviation equipment provided by the present application has a long service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope of the present application.

[0022] Figure 1 It is a comparison diagram of the initial oxidation stage and the later oxidation stage of the TGO protective film formed by the aluminide coating in the prior art; Figure 2A comparison diagram of the initial oxidation stage and the later oxidation stage of the TGO protective film formed by the anti-oxidation coating provided in the present application; Figure 3 This is a scanning electron microscope image of the unoxidized second coating prepared in Example 1; Figure 4 This is a scanning electron microscope image of the second coating after oxidation prepared in Example 2; Figure 5 This is a scanning electron microscope image of the coating after oxidation prepared in Comparative Example 1; Figure 6 It is a schematic diagram of the oxidation weight gain curves of the anti-oxidation coating of Example 1 and the coating of Comparative Example 1; Figure 7 This is a test graph of oxidation weight gain curves of the anti-oxidation coatings of Example 1 and Example 2 and the coatings of Comparative Example 1 and Comparative Example 2. DETAILED DESCRIPTION

[0023] As used herein: "Prepared from" is synonymous with "comprising." As used herein, the terms "comprising," "including," "having," "containing," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises the listed elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

[0024] The conjunction "consisting of excludes any unspecified element, step, or component. If used in a claim, this phrase renders the claim closed-ended so that it does not include materials other than those described, except for conventional impurities associated therewith. When the phrase "consisting of" appears in a clause of the body of a claim rather than immediately following the subject matter, it limits only the elements described in that clause; other elements are not excluded from the claim as a whole.

[0025] When an amount, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper preferred values ​​and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pairing of any range upper limit or preferred value with any range lower limit or preferred value, regardless of whether the range is disclosed separately. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted as including ranges "1 to 4", "1 to 3", "1 to 2", "1 to 2 and 4 to 5", "1 to 3 and 5", etc. When a numerical range is described in this article, unless otherwise stated, the range is intended to include its end values ​​and all integers and fractions within the range.

[0026] In these examples, parts and percentages are by mass unless otherwise indicated.

[0027] "Mass parts" refers to the basic unit of measurement for expressing the mass ratio of multiple components. 1 part can represent any unit mass, such as 1g or 2.689g. If we say that the mass parts of component A are a parts and the mass parts of component B are b parts, it means the ratio of the mass of component A to the mass of component B is a:b. Alternatively, it means that the mass of component A is aK and the mass of component B is bK (K is an arbitrary number, indicating a multiple factor). It should not be misunderstood that, unlike the mass parts, the sum of the mass parts of all components is not limited to 100 parts.

[0028] "And / or" is used to indicate that one or both of the stated situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0029] In a first aspect, the present application provides an anti-oxidation coating, comprising a first coating and a second coating stacked in sequence; The first coating layer comprises one or more of an MCrAlY layer, a Ni-Al layer, and a Pt-Al layer, wherein M comprises Co and / or Ni; The second coating includes nano Al-Al 2 O 3 layer.

[0030] It should be noted that the aluminide coatings such as MCrAlY coating, Ni-Al coating or Pt-Al coating in the prior art can form a dense TGO protective film at high temperature. The main component of the TGO protective film is Al 2 O 3 , and some components are oxides formed by other metals in the aluminide coating. The whole process of forming the TGO protective film includes the initial oxidation (left picture) and the late oxidation (right picture), such as Figure 1 As shown, in the initial stage of oxidation, some spinel particles are distributed on the surface of the aluminide coating, and then a TGO protective film is gradually generated. The TGO protective film is relatively thick. Generally, if the TGO thickness is greater than 8μm, there is a risk of peeling off. When TGO peels off, the inward diffusion of oxygen will be accelerated, thereby reducing the oxidation resistance.

[0031] The anti-oxidation coating provided in this application can also form a dense TGO protective film at high temperature, but the composition of the TGO protective film is only Al 2 O 3 ,like Figure 2 As shown, there are no spinel particles distributed in the early stage of oxidation (left picture) and the late stage of oxidation (right picture). The thickness of the TGO protective film is thin, there is no risk of peeling, and it can continue to provide protection.

[0032] The reason why the TGO protective film in the prior art is thick and has some spinel particles is that the Al element is oxidized and nucleated at the same time as the Ni, Co, Cr and other elements, and they are in a competitive relationship, generating disordered θ-Al 2 O 3 , chromium oxide and Ni, Co spinel (or oxide), as the oxidation proceeds, Al 2 O 3 The growth stage of Al 2 O 3 TGO layer, during this process, Al 2 O 3 Also from the loose and disordered θ-Al 2 O 3 Transformed into dense and ordered α-Al 2 O 3 However, other oxides formed in the early stage of oxidation still exist in TGO. At the same time, the competitive oxidation in the early stage of oxidation is disordered and its volume is large, resulting in a thicker TGO film layer as a whole. However, the present invention directly enters into α-Al in the early stage of oxidation. 2 O 3 During the growth phase, other oxides hardly appear, so the TGO film is thin.

[0033] It should be noted that Al 2 O 3 Dense and ordered α-Al 2 O 3 It is the key to the antioxidant effect. Due to its density, it hinders the inward diffusion of oxygen elements, thereby improving the antioxidant effect.

[0034] In some embodiments, the anti-oxidation coating satisfies at least one of the following conditions: A. The thickness of the first coating is 30 μm-200 μm; Optionally, the thickness of the first coating layer may be 30 μm, 60 μm, 90 μm, 120 μm, 150 μm, 180 μm, 200 μm or any value between 30 μm and 200 μm; B. The thickness of the second coating layer is 200nm-1000nm.

[0035] Optionally, the thickness of the second coating layer may be 200 nm, 600 nm, 800 nm, 1000 nm or any value between 200 nm and 1000 nm.

[0036] It should be noted that when the thickness of the second coating is higher than 1000 nm, the second coating is easy to peel off, and when the thickness is lower than 200 nm, the nucleation effect of the second coating is not obvious.

[0037] In some embodiments, the nano Al-Al 2 O 3 Al and Al in the layer 2 O 3 The molar ratio is 1:0.9-1.5.

[0038] Optional, nano Al-Al 2 O 3 Al and Al in the layer 2 O 3 The molar ratio can be 1:0.9, 1:1.0, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5 or any value between 1:0.9 and 1.5.

[0039] It should be noted that when nano Al-Al 2 O 3 Al and Al in the layer 2 O 3 When the molar ratio is 1:0.9-1.5, the Al content is too high, and the subsequent oxidation process needs to generate unstable needle-shaped θ-Al 2 O 3 , and then transformed into dense α-Al 2 O 3 The film structure is not good, the oxidation resistance is not improved significantly, Al 2 O 3 If the content is too high, the thermal stress difference with the substrate will be too large, and it is easy to peel off.

[0040] The second aspect of the present application provides a method for preparing the anti-oxidation coating, comprising: A first coating is provided on the surface of the substrate by using a thermal spraying method or / and an aluminizing method; In some embodiments, the MCrAlY layer is provided by a thermal spraying method, and the Ni-Al layer and / or the Pt-Al layer is provided by an aluminizing method. Exemplarily, the thermal spraying method includes a flame spraying method and / or a plasma spraying method, and the aluminizing method includes a vacuum aluminizing method and / or a gas aluminizing method. The first coating is a general anti-oxidation coating; Under a vacuum environment, magnetron sputtering is performed on the surface of the first coating to form a second coating to obtain an anti-oxidation coating.

[0041] In some embodiments, the vacuum degree of the vacuum environment is 2×10 -1 Pa-9.3×10 -2 Pa.

[0042] Optionally, the vacuum degree of the vacuum environment can be 2×10 -1 Pa, 1×10 -1 Pa, 9.5×10-2 Pa, 9.3×10 -2 Pa or 2×10 -1 Pa-9.3×10 -2 Any value between Pa.

[0043] It should be noted that the conventional vacuum requirement is 5×10 -3 Pa, and this application controls the vacuum degree to 2×10 - 1 Pa-9.3×10 -2 Pa, in order to leave a small amount of air, in which oxygen can generate Al during magnetron sputtering. 2 O 3 , vacuum degree greater than 2×10 -1 Pa, then the Al of the second coating 2 O 3 Too high, vacuum degree is less than 9.3×10 -2 Pa means the Al content is too high.

[0044] C. The bias voltage during the magnetron sputtering process is 200V-800V; Optionally, the bias voltage during magnetron sputtering is 200 V, 400 V, 600 V, 800 V or any value between 200 V and 800 V; D. The duty cycle during the magnetron sputtering process is 15%-45%.

[0045] Optionally, the duty cycle during magnetron sputtering may be 15%, 25%, 35%, 45% or any value between 15% and 45%.

[0046] It should be noted that when the bias voltage is 200V-800V and the duty cycle is in the range of 15%-45%, it helps to quickly form a thin film and improve the density of the film layer. When the bias voltage is too high and the duty cycle is too large, the gas ions will gather on the substrate, which will reduce the deposition efficiency of the Al element. When the bias voltage is too low and the duty cycle is too low, no obvious effect will be achieved.

[0047] In some embodiments, the voltage during magnetron sputtering is 200V-550V, and the current is 0.2A-0.5A.

[0048] Within this range, stable ignition and deposition in the magnetron sputtering process can be guaranteed.

[0049] In some embodiments, the method for preparing the anti-oxidation coating satisfies at least one of the following conditions: A. the temperature of the substrate and the first coating during the magnetron sputtering is 350° C.-550° C.; Optionally, the temperature of the substrate and the first coating during magnetron sputtering can be 350°C, 400°C, 450°C, 500°C, 550°C or any value between 350°C and 550°C.

[0050] B. The carrier gas flow rate of argon or nitrogen during the magnetron sputtering process is 150 mL / min-600 mL / min.

[0051] Optionally, the carrier gas flow rate of argon or nitrogen during magnetron sputtering can independently be 150 mL / min, 200 mL / min, 300 mL / min, 400 mL / min, 500 mL / min, 600 mL / min or any value between 150 mL / min and 600 mL / min.

[0052] In some embodiments, the method further includes cooling the substrate, the first coating and the second coating after the magnetron sputtering, and performing a pre-oxidation treatment in an atmospheric environment.

[0053] It should be noted that the pre-oxidation process converts the second coating into α-Al 2 O 3 Nano-level TGO can improve the oxidation resistance slightly. The pre-oxidation process is carried out at above 750°C. The Al in the second coating diffuses and transforms with the Al in the first coating, so the bonding is better and will not peel off.

[0054] In some embodiments, the pre-oxidation treatment is performed at a temperature of 750° C. to 900° C. for a time of 2 h to 8 h.

[0055] Optionally, the temperature of the pre-oxidation treatment can be 750°C, 800°C, 850°C, 900°C or any value between 750°C and 900°C, and the time can be 2h, 4h, 6h, 8h or any value between 2h and 8h.

[0056] A third aspect of the present application provides a high-temperature component, comprising a substrate and an anti-oxidation coating disposed on the surface of the substrate; The anti-oxidation coating includes the anti-oxidation coating or the anti-oxidation coating prepared by the preparation method of the anti-oxidation coating; The substrate includes a nickel-based high-temperature alloy and / or a single crystal high-temperature alloy.

[0057] It should be noted that the high-temperature components include but are not limited to one or more of turbine blades, combustion chambers, and working blades.

[0058] A fourth aspect of the present application provides an aviation equipment, comprising the above-mentioned high-temperature component.

[0059] It should be noted that aviation equipment includes but is not limited to aircraft engines and gas turbines.

[0060] The embodiments of the present application will be described in detail below in conjunction with specific examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present application and should not be considered as limiting the scope of the present application. If specific conditions are not specified in the examples, they are carried out according to normal conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0061] Example 1 The first aspect of the present embodiment provides an anti-oxidation coating, comprising a first coating and a second coating stacked in sequence; the first coating is an MCrAlY layer, wherein M is Co and Ni, and the second coating is a nano-Al-Al 2 O 3 layer; The thickness of the first coating is 60 μm, the thickness of the second coating is 826 nm, and the nano-Al-Al 2 O 3 Al and Al in the layer 2 O 3 The molar ratio is 1:1.2.

[0062] A second aspect of the present embodiment provides a method for preparing an anti-oxidation coating, comprising: S1: spraying an MCrAlY layer on the surface of a substrate by supersonic flame spraying, wherein the substrate is a GH4169 nickel-based high-temperature alloy; S2: At a vacuum degree of 1.0×10 -1 Pa environment, the substrate treated in step S1 was magnetron sputtered to set nano Al-Al 2 O 3 layer to obtain an anti-oxidation coating, wherein the temperature of the substrate during magnetron sputtering is 450°C, the carrier gas flow rate of argon is 300mL / min, the voltage is 300V, the bias voltage is 550V, the duty cycle is 30%, and the current is 0.3A.

[0063] The scanning electron microscopy of the second coating in the anti-oxidation coating is as follows Figure 3 shown.

[0064] A third aspect of the present embodiment provides a high-temperature component, comprising the above-mentioned substrate and an anti-oxidation coating arranged on the surface of the substrate.

[0065] Example 2 The difference from Example 1 is that in this example, the substrate after magnetron sputtering is further cooled to room temperature and then subjected to pre-oxidation treatment in an atmospheric environment. The pre-oxidation treatment temperature is 850°C and the time is 4 hours. The scanning electron microscopy of the second coating is as follows: Figure 4 shown.

[0066] Example 3 The difference from Example 1 is that a Ni—Al layer is provided on the surface of the substrate by an aluminizing method.

[0067] Example 4 The difference from Example 1 is that a Pt—Al layer is provided on the surface of the substrate by using the CVD method.

[0068] Comparative Example 1 The difference from Example 1 is that no nano Al-Al 2 O 3 layer.

[0069] The SEM of the coating prepared in this comparative example after oxidation (same as the conditions in Example 1) is as follows Figure 5 shown.

[0070] The schematic diagram of the oxidation weight gain curve of the anti-oxidation coating of Example 1 and the coating of this comparative example is as follows: Figure 6 As shown, the left picture is the coating of this comparative example, and the right picture is the anti-oxidation coating of Example 1. Figure 6 It can be seen from the slope of the curve of oxidation weight gain and oxidation time in the initial stage of oxidation that compared with the non-nano Al-Al 2 O 3 Comparative Example 1 of the layer, Example 1 Due to the nano Al-Al 2 O 3 The presence of the layer significantly reduces the weight gain in the initial oxidation stage, and the oxidation rate (curve slope) in the initial oxidation stage is also significantly reduced. This is because the competitive oxidation stage is skipped in the initial oxidation stage of Example 1, and Al is rapidly oxidized to dense and ordered α-Al 2 O 3 .

[0071] Comparative Example 2 The difference from Example 1 is that the nano Al-Al 2 O 3 The layer is replaced by a pure aluminum layer.

[0072] The oxidation weight gain curves of the coatings provided in Example 1, Example 2, Comparative Example 1 and Comparative Example 2 are tested as follows: Figure 7 shown.

[0073] Comparative Example 3 The difference from Example 1 is that the nano Al-Al 2 O 3 Layer replaced with pure Al 2 O 3 layer.

[0074] Comparative Example 4 The difference from Example 1 is that the first coating layer is not provided.

[0075] Comparative Example 5 The difference from Example 1 is that the thickness of the second coating layer is 100 nm.

[0076] Comparative Example 6 The difference from Example 1 is that the nano Al-Al 2 O 3 Al and Al in the layer 2 O 3 The molar ratio is 1:3.

[0077] Comparative Example 7 The difference from Example 1 is that when providing the second coating, the magnetron sputtering is replaced by electroplating.

[0078] Comparative Example 8 The difference from Example 1 is that the vacuum degree is 8.0×10 -1 Pa.

[0079] The above examples and comparative examples were subjected to oxidation weight gain test (1100° C., 100 h). The specific test results are shown in Table 1.

[0080] Table 1 High temperature oxidation resistance test

[0081] Among them, Example 2 is pre-oxidized to directly generate α-Al in the second coating 2 O 3 , while in Examples 1, 3, and 4, α-Al is rapidly generated after anti-oxidation. 2 O 3 .

[0082] The coatings formed from the above-mentioned embodiments and comparative examples were subjected to oxidation tests. The oxidation tests were divided into three stages: initial oxidation, middle oxidation and late oxidation. The specific data are shown in Table 2.

[0083] Table 2 Oxidation test

[0084] Among them, the TGO thickness increases in the competitive oxidation stage during the initial oxidation process, but the θ-Al 2 O 3 It and other oxides are not dense and ordered structures and have no antioxidant effect; α-Al in the initial oxidation process 2 O 3 TGO in the production stage has high density and is resistant to oxidation; α-Al in the initial oxidation process 2 O3 α-Al in the formation stage and mid-oxidation process 2 O 3 The growth stage is the main stage of anti-oxidation; In the late stage of oxidation, the service life of the coating has expired and it has no anti-oxidation effect.

[0085] It should be noted that the service life in the later stage of oxidation can generally reach thousands of times.

[0086] analyze: From the results in Table 1, it can be seen that in terms of the anti-oxidation effect, the oxidation resistance of the four embodiments is significantly improved, among which the oxidation resistance of embodiment 2 is better. The reason is that the second coating does not need to go through the competitive oxidation stage in the early stage of oxidation, and directly generates an ordered and dense α-Al 2 O 3 The second coating of Comparative Example 2 is pure Al. Although there are no other elements to compete for oxidation, due to the absence of Al 2 O 3 Nucleation will first generate loose and unstable θ-Al 2 O 3 , and then converted into α-Al 2 O 3 Comparative Example 1 is the conventional technology at present. The process control of Comparative Examples 3, 6, 7, and 8 causes the second coating to peel off after deposition or at the beginning of the anti-oxidation test. The second coating of Comparative Example 5 is too thin to have a significant effect. Therefore, the oxidation process of Comparative Examples 1, 3, 5, 6, 7, and 8 is consistent with the oxidation mechanism of the conventional technology. θ-Al 2 O 3 Compared with other oxides, the structure of these products is not dense, not protective, and has a large volume, which makes the generated TGO film relatively thick; Comparative Example 4 does not have the first coating, and the Al content in the second coating and the substrate is insufficient to complete the 100h anti-oxidation test, and there is a significant increase in weight gain in the later stage of oxidation.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0088] In addition, those skilled in the art will appreciate that, although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the above claims, any one of the claimed embodiments may be used in any combination. The information disclosed in this background technology section is intended only to deepen the understanding of the overall background technology of the present application and should not be regarded as an admission or in any form of implication that the information constitutes prior art known to those skilled in the art.

Claims

1. An anti-oxidation coating, characterized in that: It includes a first coating layer and a second coating layer which are stacked in sequence; The first coating layer comprises one or more of an MCrAlY layer, a Ni-Al layer, and a Pt-Al layer, wherein M comprises Co and / or Ni; The second coating layer includes a nano-Al-Al2O3 layer.

2. The anti-oxidation coating according to claim 1, characterized in that: At least one of the following conditions is met: A. The thickness of the first coating is 30 μm-200 μm; B. The thickness of the second coating layer is 200nm-1000nm.

3. The anti-oxidation coating according to claim 1 or 2, characterized in that: The molar ratio of Al to Al2O3 in the nano Al-Al2O3 layer is 1:0.9-1.

5.

4. A method for preparing the anti-oxidation coating according to any one of claims 1 to 3, characterized in that: include: A first coating is provided on the surface of the substrate by using a thermal spraying method or / and an aluminizing method; Under a vacuum environment, magnetron sputtering is performed on the surface of the first coating to form a second coating to obtain an anti-oxidation coating.

5. The method for preparing the anti-oxidation coating according to claim 4, characterized in that: The vacuum degree of the vacuum environment is 2×10 -1 Pa-9.3×10 -2 Pa.

6. The method for preparing the anti-oxidation coating according to claim 4, characterized in that: At least one of the following conditions is met: A. the temperature of the substrate and the first coating during the magnetron sputtering is 350° C.-550° C.; B. The carrier gas flow rate of argon or nitrogen during the magnetron sputtering process is 150mL / min-600mL / min; C. The bias voltage during the magnetron sputtering process is 200V-800V; D. The duty cycle during the magnetron sputtering process is 15%-45%.

7. The method for preparing the anti-oxidation coating according to any one of claims 4 to 6, characterized in that: Also includes: The substrate, the first coating and the second coating after the magnetron sputtering are cooled and pre-oxidized in an atmospheric environment.

8. The method for preparing the anti-oxidation coating according to claim 7, characterized in that: The pre-oxidation treatment is carried out at a temperature of 750° C. to 900° C. and for a time of 2 h to 8 h.

9. A high temperature component, characterized in that: It comprises a substrate and an anti-oxidation coating arranged on the surface of the substrate; The anti-oxidation coating comprises the anti-oxidation coating according to any one of claims 1 to 3 or the anti-oxidation coating prepared by the method for preparing the anti-oxidation coating according to any one of claims 4 to 8; The substrate includes a nickel-based high-temperature alloy and / or a single crystal high-temperature alloy.

10. An aviation device, characterized in that: Comprising the high-temperature component as claimed in claim 9.

Images