A method for evaluating the thickness of the oxide layer around high-temperature gas-film holes in nickel-based single crystal alloys

Abstract

The present invention belongs to the field of oxide layer thickness analysis, and relates to a method for evaluating the oxide layer thickness around high-temperature holes of film holes in nickel-based single crystal alloys. The angle value of the film holes of the initial sample of the nickel-based single crystal alloy is obtained; the initial sample containing the film holes is subjected to aging tests of different times to obtain metallographic samples, and the microstructure morphology and aging test time of the metallographic samples are obtained; the average thickness of the oxide layer of the metallographic samples is obtained according to the microstructure morphology; and a new oxidation kinetic equation is established by fitting the existing oxidation kinetic equation according to the angle value of the film holes, the aging test time, and the average thickness of the oxide layer. By introducing the angle influencing factor, the present invention can more accurately predict the oxide layer thickness at different angles, more accurately describe the growth law of the oxide layer thickness of nickel-based single crystal alloys under high-temperature aging conditions, and improve the accuracy and reliability of the prediction.

Description

Technical Field

[0001] The invention belongs to the field of oxide layer thickness analysis and relates to a method for evaluating the thickness of an oxide layer around a high-temperature hole of a nickel-based single crystal alloy gas film hole. Background Art

[0002] Nickel-based single-crystal superalloys have attracted considerable attention for their exceptional high-temperature performance and have become the material of choice for the manufacture of advanced aeroengine and gas turbine blades. These alloys offer advantages such as high high-temperature strength, stable microstructure, and excellent casting processability. Thrust-to-weight ratio is a key performance indicator for aeroengines, and increasing turbine inlet temperature is one of the primary approaches to improving this ratio. However, current developments in nickel-based single-crystal superalloys are insufficient to meet these high turbine inlet temperatures. Therefore, the key to improvement lies in efficient turbine blade cooling technology, with film cooling, a key cooling method, ensuring reliable engine operation. Nickel-based single-crystal superalloys undergo certain microstructural changes at high temperatures, impacting blade performance. Furthermore, the introduction of film pores disrupts the geometric continuity of the blade structure. In actual operation, turbine blades face complex high-temperature environments, and the presence of film pores significantly shortens blade service life.

[0003] Aeroengine blades are complex structures, with film holes at different angles at different locations, resulting in varying performance. Due to their complex service environments, prolonged exposure to high temperatures can lead to severe oxidative corrosion, which significantly shortens blade life. The impact of high-temperature oxidation on mechanical properties cannot be ignored. Therefore, evaluating the thickness of the high-temperature oxide layer surrounding nickel-based single crystal alloy film holes at different angles is crucial.

[0004] The existing oxidation kinetic equation provides a method for evaluating the thickness of the oxide layer, as shown in the following formula.

[0005] (Δh) n =K p t

[0006] Where Δh is the increase in the oxide layer or γ′ during the oxidation process; t is the oxidation time; K p is the isothermal parabolic oxidation thickening rate constant, and n is the oxidation thickening rate exponent. However, the existing oxidation kinetics equation does not consider the influence of the film pore angle, resulting in large evaluation errors. Summary of the Invention

[0007] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a method for evaluating the thickness of the oxide layer around the high-temperature hole of the nickel-based single crystal alloy film hole. By introducing the angle influencing factor, the present invention can more accurately predict the oxide layer thickness at different angles, more accurately describe the growth law of the oxide layer thickness of the nickel-based single crystal alloy under high-temperature aging conditions, and improve the accuracy and reliability of the prediction.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] The present invention discloses a method for evaluating the thickness of a high-temperature periphery oxide layer of a nickel-based single crystal alloy gas film hole, comprising the following steps:

[0010] Obtaining the angle value of the air film hole of the initial sample of the nickel-based single crystal alloy;

[0011] Perform aging tests at different times on the initial sample containing air film pores to obtain metallographic samples, and obtain the microstructure morphology and aging test time of the metallographic samples;

[0012] Obtain the average thickness of the oxide layer of the metallographic specimen based on the microstructural morphology;

[0013] A new oxidation kinetic equation was established based on the angle value of the air film pores, the time of the aging test and the average thickness of the oxide layer, combined with the existing oxidation kinetic equation.

[0014] Furthermore, the steps for processing the air film holes of the initial nickel-based single crystal alloy sample are as follows:

[0015] The nickel-based single crystal alloy is subjected to wire cutting to obtain an initial sample, and air film holes with different angles are machined on the initial sample.

[0016] Furthermore, the processing methods of the air film hole include electric spark machining, laser machining and electrochemical machining.

[0017] Furthermore, the initial sample has a block structure.

[0018] Furthermore, the initial sample containing air film pores was subjected to aging tests at different times to obtain the metallographic samples as follows:

[0019] Aging tests were conducted for different time periods on initial samples with air film holes at different angles;

[0020] Mechanical grinding and polishing of the flat surfaces of the initial specimens after aging tests;

[0021] The surface of the initial sample after grinding and polishing was corroded with CuSO4 corrosive solution to obtain a metallographic sample that can be observed under a scanning electron microscope.

[0022] Furthermore, the plane of the initial sample after the aging test is mechanically ground and polished as follows:

[0023] At least one flat surface of the initial aged test specimens shall be mechanically ground and polished.

[0024] Furthermore, the temperature of the aging test is 980°C to 1100°C.

[0025] Furthermore, the microstructure morphology of the metallographic sample is obtained, as follows:

[0026] The microstructure of the metallographic sample was observed using a scanning electron microscope, and the basic morphology of the oxide layer around the air film pores was observed and obtained.

[0027] Furthermore, the average thickness of the oxide layer of the metallographic sample is obtained according to the microstructure morphology, as follows:

[0028] The average thickness of the oxide layer around the air film pores in the metallographic specimens was determined based on the microstructure by combining manual measurement with ImageJ calculation software. The average thickness of the oxide layer of the metallographic specimens at different air film pore angles and different aging test times was statistically analyzed.

[0029] Furthermore, the new oxidation kinetic equation is as follows:

[0030] h=(lθ q +m)t i +bθ c +d

[0031] Wherein, h is the thickness of the oxide layer during the oxidation process, l is the correction coefficient of the instantaneous angle effect, θ is the inclination angle of the air film hole, q is the correction index of the instantaneous angle effect, t is the oxidation time, i is the thickening rate index affected by time, b is the angle thickening coefficient, c is the thickening rate index affected by angle, and m and d are constants.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1. The present method obtains the angle value of the film pores of the initial nickel-based single crystal alloy sample. By introducing the angle influencing factor, namely the angle value of the film pores, the existing oxidation kinetics equation is improved and modified. This enables the oxidation kinetics equation to more accurately describe the growth pattern of the oxide layer thickness of nickel-based single crystal alloys under high-temperature aging conditions, improving the accuracy and reliability of the prediction.

[0034] The method of the present invention obtains metallographic samples by performing aging tests of different times on initial samples containing air film pores, obtains the microstructure morphology of the metallographic samples and the time of the aging test, and introduces high-temperature aging conditions, which is conducive to improving the accuracy and reliability of the analysis results.

[0035] The method of the present invention determines the average oxide layer thickness of a metallographic specimen based on microstructural morphology. A new oxidation kinetic equation is then constructed by fitting the existing oxidation kinetic equation based on the angle of the film hole, the duration of the aging test, and the average oxide layer thickness. By introducing an angle influencing factor, the new oxidation kinetic equation accounts for the effect of the film hole machining angle on the oxide layer thickness. This allows for more accurate predictions of oxide layer thickness at different angles and more precisely describes the growth pattern of oxide layer thickness in nickel-based single crystal alloys under high-temperature aging conditions, improving the accuracy and reliability of the predictions.

[0036] 2. The method of the present invention improves and modifies the existing oxidation kinetics equation by introducing an angle influence factor and a correction coefficient, so that the oxidation kinetics equation can more accurately describe the growth law of the oxide layer thickness of nickel-based single crystal alloys under high-temperature aging conditions, thereby improving the accuracy and reliability of the prediction. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 1 is a method flow chart of an embodiment of the present invention;

[0038] Figure 2 It is a three-dimensional schematic diagram of the sample structure of the present invention;

[0039] Figure 3 This is a front view of the sample structure of the present invention;

[0040] Figure 4 is a top view of the sample structure of the present invention;

[0041] Figure 5 This is a schematic diagram showing the oxidation time and the average thickness of the oxide layer according to the present invention;

[0042] Figure 6 This is a schematic diagram showing the fitting of angles and average thickness of the oxide layer according to the present invention;

[0043] Figure 7 It is a three-dimensional graph of oxidation time, angle and average thickness of the oxide layer of the present invention;

[0044] Figure 8 Flow chart of the method of the present invention.

[0045] Among them, 1. Initial sample; 2. Air film hole. DETAILED DESCRIPTION

[0046] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0047] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0048] The present invention is described in further detail below with reference to the accompanying drawings:

[0049] See also Figure 8 The present invention discloses a method for evaluating the thickness of the high-temperature periphery oxide layer of a nickel-based single crystal alloy gas film hole, comprising the following steps:

[0050] S1. Obtain the angle value of the air film hole 2 of the initial nickel-based single crystal alloy sample 1;

[0051] Preferably, the steps for processing the air film hole 2 of the initial nickel-based single crystal alloy sample 1 are as follows:

[0052] The nickel-based single crystal alloy is subjected to wire cutting to obtain an initial sample, and air film holes 2 with different angles are machined on the initial sample.

[0053] Preferably, the processing methods of the air film hole 2 include electric spark machining, laser machining and electrochemical machining.

[0054] Preferably, the initial sample 1 is a block structure, and the length, width and height of the initial sample 1 are 10 mm, 8 mm and 1.2 mm respectively.

[0055] S2. The initial sample 1 containing the air film hole 2 is subjected to aging tests at different times to obtain metallographic samples, and the microstructure morphology of the metallographic samples and the aging test time are obtained;

[0056] Preferably, the initial sample containing the air film pores is subjected to aging tests for different time periods to obtain metallographic samples as follows:

[0057] Aging tests were conducted for different time periods on initial samples with air film holes at different angles;

[0058] Mechanical grinding and polishing of the flat surfaces of the initial specimens after aging tests;

[0059] The surface of the initial sample after grinding and polishing was corroded with CuSO4 corrosive solution to obtain a metallographic sample that can be observed under a scanning electron microscope.

[0060] Preferably, the plane of the initial sample after the aging test is mechanically ground and polished as follows:

[0061] At least one flat surface of the initial aged test specimens shall be mechanically ground and polished.

[0062] Preferably, the temperature of the aging test is 980°C to 1100°C.

[0063] Preferably, the microstructure morphology of the metallographic sample is obtained as follows:

[0064] The microstructure of the metallographic sample was observed using a scanning electron microscope, and the basic morphology of the oxide layer around the air film pores was observed and obtained.

[0065] S3. Obtain the average thickness of the oxide layer of the metallographic specimen based on the microstructure morphology, as follows:

[0066] The average thickness of the oxide layer around the air film pores in the metallographic specimens was determined based on the microstructure by combining manual measurement with ImageJ calculation software. The average thickness of the oxide layer of the metallographic specimens at different air film pore angles and different aging test times was statistically analyzed.

[0067] S4. A new oxidation kinetic equation is established based on the angle value of the air film hole 2, the time of the aging test and the average thickness of the oxide layer, combined with the existing oxidation kinetic equation.

[0068] Preferably, the new oxidation kinetic equation is as follows:

[0069] h=(lθ q +m)t i +bθ c +d

[0070] Wherein, h is the thickness of the oxide layer during the oxidation process, l is the correction coefficient of the instantaneous angle effect, θ is the inclination angle of the air film hole, q is the correction index of the instantaneous angle effect, t is the oxidation time, i is the thickening rate index affected by time, b is the angle thickening coefficient, c is the thickening rate index affected by angle, and m and d are constants.

[0071] See also Figure 8 In another feasible embodiment of the present invention, the following is adaptively modified according to the circumstances. The angle value of the air film hole 2 of the initial sample 1 of the nickel-based single crystal alloy is obtained, and the angle influencing factor, i.e., the angle value of the air film hole 2, is introduced to construct a new oxidation kinetics equation. By adding the angle influencing factor, the influence of the inclination angle of the air film hole is taken into account, which is conducive to reducing the error of the new oxidation kinetics equation; the initial sample containing the air film hole is subjected to aging tests of different times to obtain a metallographic sample, and the microstructure morphology and the time of the aging test of the metallographic sample are obtained. The microstructure morphology is obtained to facilitate the measurement of the thickness of the oxide layer at the air film hole; the average thickness of the oxide layer of the metallographic sample is obtained according to the microstructure morphology; a new oxidation kinetics equation is established based on the angle value of the air film hole 2, the time of the aging test and the average thickness of the oxide layer, combined with the existing oxidation kinetics equation, and the mathematical relationship between the oxide layer, angle and time is further obtained to establish a new oxidation kinetics equation. The new oxidation kinetics equation can be used to evaluate the thickness of the oxide layer around the high-temperature holes of the air film holes at different angles. By introducing the angle influencing factor, the new oxidation kinetics equation can more accurately predict the thickness of the oxide layer at different angles, and more accurately describe the growth law of the oxide layer thickness of nickel-based single crystal alloys under high-temperature aging conditions, thereby improving the accuracy and reliability of the prediction.

[0072] Example 1:

[0073] See also Figure 1 The present invention discloses a method for evaluating the thickness of the high-temperature periphery oxide layer of a nickel-based single crystal alloy gas film hole, and the specific steps are as follows:

[0074] Step 1: obtaining an initial sample of a nickel-based single crystal alloy, and processing an air film hole with a preset angle on the initial sample;

[0075] Step 2: performing an aging test on the sample at a preset temperature for different preset times;

[0076] Step 3: Processing the sample after the test to obtain a metallographic sample;

[0077] Step 4: observing the metallographic sample to obtain the microstructure morphology of the metallographic sample;

[0078] Step 5: Calculating the average thickness of the oxide layer in the metallographic sample at different preset angles and different preset times according to the microstructure morphology;

[0079] Step 6: Establish a new oxidation kinetic equation based on the oxidation kinetic equation and the average thickness of the oxide layer.

[0080] Introducing the oxide layer angle factor effectively characterizes the oxide layer thickness pattern. This provides a rational basis for future research on the microstructural stability of nickel-based single crystal alloys under high-temperature aging conditions, improving the efficiency of alloy stability analysis and further ensuring the accuracy of blade reliability analysis. The following details the above steps.

[0081] In step 1, an initial sample of nickel-based single crystal alloy is obtained, and a gas film hole with a preset angle is processed on the initial sample; the nickel-based single crystal alloy is subjected to wire cutting to obtain the initial sample, such as Figure 2 、 Figure 3 and Figure 4 As shown, the initial sample is a block structure with a length, width and height of 10 mm, 8 mm and 1.2 mm respectively. The electric spark machining process is used to machine the air film holes with angles of 30 degrees, 60 degrees and 90 degrees.

[0082] In step 2, the sample is subjected to an aging test at a preset temperature for different preset times. The preset temperature may be 980 degrees Celsius or 1100 degrees Celsius. In an exemplary embodiment disclosed herein, the preset temperature is 980 degrees Celsius. The preset times are 1 hour, 10 hours, 100 hours, and 200 hours, respectively.

[0083] In step 3, the initial sample after the test is processed to obtain a metallographic sample. After the test, a 10 mm x 8 mm plane of the initial sample is mechanically ground and polished, and then the polished initial sample surface is corroded with a CuSO4 (copper sulfate) corrosive solution to obtain a metallographic sample that can be observed under a scanning electron microscope. When preparing the metallographic sample, only one surface of the initial sample can be processed, or multiple edges can be processed simultaneously. Alternatively, the entire initial sample can be mechanically ground and polished, and then the polished alloy surface can be corroded with a CuSO4 (copper sulfate) corrosive solution.

[0084] In step 4, the metallographic sample is observed to obtain the microstructure morphology of the metallographic sample; the microstructure morphology of the alloy is observed using a scanning electron microscope, and the basic morphology of the oxide layer around the pores is observed.

[0085] In step 5, the average thickness of the oxide layer in the metallographic sample at different preset angles and different preset times is calculated based on the microstructure morphology; the average thickness of the oxide layer around the alloy pores is measured by combining manual measurement with Image J measurement software, and the average thickness of the alloy oxide layer at different aging times is calculated.

[0086] In step 6, a new oxidation kinetic equation is established based on the oxidation kinetic equation and the average thickness of the oxide layer.

[0087] The original oxidation kinetic equation is:

[0088] (Δh) n =K p t (1)

[0089] Where Δh is the increase in the oxide layer during the oxidation process; t is the oxidation time; K p is the isothermal parabolic oxidation thickening rate constant, and n is the oxidation thickening rate exponent, which is a constant.

[0090] It is known that the oxide layer thickness of nickel-based single crystal film holes follows a formula. However, under the specific conditions of EDM film holes, the influence of initial processing on the oxidation kinetics curve cannot be ignored. Therefore, considering the influence of initial processing on the oxide layer thickness, the following correction is made to the formula:

[0091] h=Kt i +a (2)

[0092] Where: K and a are constants, and i is the thickening rate index affected by time. Figure 5 This is a fitting curve of the oxide layer thickness under different angle conditions. It can be seen from the figure that the change in the angle of the air film hole makes the obtained oxide layer thickness curve different, indicating that the difference in angle will also cause the difference in the change of the oxide layer thickness. The thickening rate index i at different angles is almost the same, indicating that the angle has little effect on the thickening rate index i, while the constants K and a change more significantly with the change of angle, indicating that K and a are both functions of the angle θ. Therefore, formula (2) can be modified to:

[0093]

[0094] Where: f(θ) and is a function of θ, where θ is the inclination angle of the air film hole, see Figure 2 , θ=θ2 or θ=π-θ1. Then we can study f(θ) and like Figure 6 As shown in the figure, the function expression of f(θ) can be obtained by fitting the time coefficient K in the fitting formula at different angles. It can be seen from the figure that the fitting results of K in the thickening formula at different angles are in the form of a parabola. Therefore, the expression of f(θ) is shown in formula (4):

[0095] f(θ)=lθ q +m (4)

[0096] Where: l, q and m are all constants. It can be found that when q = 0.5, the experimental data can be well fitted.

[0097] Again Expand the research, and we can see from the formula that when t=0, the thickness of the oxide layer is like Figure 6 As shown in the figure, the oxide layer thickness data at t = 0 is fitted. It can be seen from the figure that the oxide layer thickness at t = 0 also shows a parabolic trend. Therefore, The expression of is shown in formula (5):

[0098]

[0099] Where: c is the thickening rate index under the influence of angle, b and d are constants. It can be found that when c = 0.5, the experimental data can be well fitted. Therefore, f(θ) and The expression of can be rewritten as:

[0100] h=(lθ q +m)t i +bθ c +d (6)

[0101] Where: l is the correction coefficient of instantaneous angle effect, q is the correction index of instantaneous angle effect, i is the thickening rate index of time effect, b is the angle thickening coefficient, c is the thickening rate index of angle effect, m and d are constants, and the three-dimensional fitting diagram is as follows: Figure 7 shown.

[0102] Compared with the prior art, the present invention has the following technical effects:

[0103] More accurate analysis: By incorporating the angle effect, the oxidation kinetics equation can more accurately predict the oxide layer thickness at different angles. This accuracy can be controlled within 15%, making it more reliable than existing technologies.

[0104] Improved analysis efficiency: By establishing a new oxidation kinetics equation, the microstructural stability of nickel-based single crystal alloys under high-temperature aging conditions can be more effectively analyzed. This provides a more reasonable analysis basis, thereby improving the efficiency of alloy stability analysis.

[0105] Improved accuracy of blade reliability analysis: This technology can help improve the accuracy of blade reliability analysis. By deeply studying and predicting the thickness of the oxide layer, it can better assess the performance and life of the blade in high-temperature environments.

[0106] Expanded knowledge: This invention expands our understanding of oxidation kinetics and incorporates the angle factor into the prediction of oxide layer thickness. This approach can provide new insights and methods for research in related fields.

[0107] The present invention improves and modifies the existing oxidation kinetics equation by introducing an angle-influencing factor and a correction coefficient. This allows the oxidation kinetics equation to more accurately describe the growth pattern of the oxide layer thickness of nickel-based single crystal alloys under high-temperature aging conditions, improving the accuracy and reliability of predictions.

[0108] The present invention incorporates an angle-influencing factor: The oxidation kinetics equation considers the effect of the film hole processing angle on the oxide layer thickness. This aspect, which is less addressed in the prior art, allows for a more comprehensive consideration of the impact of different processing conditions on oxide layer formation.

[0109] Improved accuracy and controllability: The new oxidation kinetics equation can maintain prediction accuracy within 15%. This means that in practical applications, the method can provide high prediction accuracy and controllability, making the assessment of alloy properties and stability more accurate and reliable.

[0110] The above content is only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for evaluating the thickness of the high-temperature surrounding oxide layer of a nickel-based single crystal alloy gas film hole, characterized in that: The following steps are involved: Obtaining an angle value of an air film hole (2) of an initial nickel-based single crystal alloy sample (1); Performing aging tests of different times on the initial sample (1) containing the air film pores (2) to obtain metallographic samples, and obtaining the microstructure morphology of the metallographic samples and the time of the aging test; The average thickness of the oxide layer of the metallographic specimen is obtained according to the microstructure morphology, as follows: The average thickness of the oxide layer around the air film pores in the metallographic specimens was measured based on the microstructure using a combination of manual and ImageJ measurement software. The average thickness of the oxide layer at different air film pore angles and different aging test times was statistically analyzed. A new oxidation kinetic equation is established based on the angle value of the air film hole (2), the time of the aging test and the average thickness of the oxide layer and the existing oxidation kinetic equation; The new oxidation kinetic equation is as follows: h=(lθ q +m)t i +bθ c +d Wherein, h is the thickness of the oxide layer during the oxidation process, l is the correction coefficient of the instantaneous angle effect, θ is the inclination angle of the air film hole, q is the correction index of the instantaneous angle effect, t is the oxidation time, i is the thickening rate index affected by time, b is the angle thickening coefficient, c is the thickening rate index affected by angle, and m and d are constants.

2. The method for evaluating the thickness of the high-temperature periphery oxide layer of a nickel-based single crystal alloy gas film hole according to claim 1, characterized in that: The specific steps for processing the air film hole (2) of the nickel-based single crystal alloy initial sample (1) are as follows: A nickel-based single crystal alloy is subjected to wire cutting to obtain an initial sample (1), and air film holes (2) with different angles are machined on the initial sample (1).

3. The method for evaluating the thickness of the high-temperature periphery oxide layer of a nickel-based single crystal alloy gas film hole according to claim 2, characterized in that: The processing methods of the air film hole (2) include electric spark processing, laser processing and electrochemical processing.

4. The method for evaluating the thickness of the high-temperature periphery oxide layer of a nickel-based single crystal alloy gas film hole according to claim 2, characterized in that: The initial sample (1) is a block structure.

5. The method for evaluating the thickness of the high-temperature periphery oxide layer of a nickel-based single crystal alloy gas film hole according to claim 1, characterized in that: The metallographic samples obtained by carrying out aging tests for different time periods on the initial samples containing air film pores are as follows: Aging tests were conducted for different time periods on initial samples with air film holes at different angles; Mechanical grinding and polishing of the flat surfaces of the initial specimens after aging tests; The surface of the initial sample after grinding and polishing was corroded with CuSO4 corrosive solution to obtain a metallographic sample that can be observed under a scanning electron microscope.

6. The method for evaluating the thickness of the high-temperature periphery oxide layer of a nickel-based single crystal alloy gas film hole according to claim 5, characterized in that: The mechanical grinding and polishing of the plane of the initial sample after the aging test is as follows: At least one flat surface of the initial aged test specimens shall be mechanically ground and polished.

7. The method for evaluating the thickness of the high-temperature periphery oxide layer of a nickel-based single crystal alloy gas film hole according to claim 5, characterized in that: The temperature of the aging test is 980°C to 1100°C.

8. The method for evaluating the thickness of the high-temperature periphery oxide layer of a nickel-based single crystal alloy gas film hole according to claim 1, characterized in that: The microstructure morphology of the metallographic sample is obtained as follows: The microstructure of the metallographic sample was observed using a scanning electron microscope, and the basic morphology of the oxide layer around the air film pores was observed and obtained.

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