A method and system for analyzing the high-cycle fatigue strength of coated blades

Abstract

The present invention relates to the technical field of aeroengines, and discloses a method and system for analyzing the high-cycle fatigue strength of a coated blade. By constructing a third linear relationship function between the strain and amplitude corresponding to the position of the maximum vibration stress of the coated turbine blade at the working temperature, the test amplitude for carrying out the high-cycle fatigue test of the coated blade at the working temperature is obtained. The strength analysis test parameters determined in the strength analysis method of the present invention not only consider the influence of the coating on the vibration characteristics of the blade, but also ensure an accurate transition from the room-temperature test data to the fatigue strength analysis at the working temperature through precise conversion coefficient adjustment, improve the reliability of the high-cycle fatigue strength of the coated turbine blade, thereby improving the reliability of the engine strength life design, and providing a scientific and efficient solution for the high-cycle fatigue strength evaluation of the coated turbine blade.

Description

Technical Field

[0001] The present invention relates to the technical field of aeroengines, and discloses a method and system for analyzing the high-cycle fatigue strength of coated blades. Background Art

[0002] The turbine blade is one of the important components of an aeroengine. The working environment is extremely harsh. When working, it bears a large centrifugal force and thermal stress, and there is also vibration stress. When the vibration stress amplitude is large enough, it will cause high-cycle fatigue failure of the turbine rotor blade. In the past few decades, high-cycle fatigue failure has become one of the main causes of turbine rotor blade failures. Therefore, the structural strength designers of aeroengines pay more attention to the high-cycle fatigue performance of blades.

[0003] The temperature-bearing capacity of the turbine rotor blade of a high-performance engine has reached the limit of metal materials. Due to the good heat insulation effect, the thermal barrier coating is widely used on the turbine blade of the engine to improve the thermal fatigue life. Therefore, when conducting the high-cycle fatigue test of the turbine rotor blade on a vibration table, the blade coating needs to be considered. The ceramic outer layer of the thermal barrier coating is relatively smooth and cannot paste strain gauges to obtain the strain value at the maximum stress position. A strain amplitude conversion method between uncoated blades and partially de-coated blades is required, which is applied to the strain-amplitude function relationship of coated blades. At the same time, it is required that the blade de-coating process does not affect the high-cycle fatigue strength of the blade.

[0004] The domestic high-temperature strain gauge pasting process is complex, and the heavy quality causes the vibration characteristics of the blade to change. The strain error of the strain-amplitude function directly obtained by using the high-temperature strain gauge is about 30%. The obtained high-cycle fatigue strength error is relatively large and cannot be applied to the high-cycle fatigue design of turbine blades. Summary of the Invention

[0005] The purpose of the present invention is to provide a method and system for analyzing the high-cycle fatigue strength of coated blades, which can ensure an accurate transition from room-temperature test data to fatigue strength analysis at working temperature, improve the reliability of the high-cycle fatigue strength of coated turbine blades, and thus improve the reliability of the engine strength life design.

[0006] In order to achieve the above technical effects, the technical solution adopted by the present invention is:

[0007] A method for analyzing the high-cycle fatigue strength of coated blades includes:

[0008] Carrying out vibration stress distribution tests on multiple uncoated turbine blades of the same batch at room temperature on a vibration table by using the clamping tenon method to obtain the actual maximum vibration stress position of the uncoated turbine blade;

[0009] Select multiple turbine blades with coatings from the same batch. According to the actual maximum vibration stress position of the uncoated turbine blades, remove the thermal barrier coating from the corresponding maximum vibration stress area on the coated turbine blades. Use the clamping tenon method to test the strain and amplitude at the position where the thermal barrier coating is removed from the coated turbine blades at room temperature on a vibration table, and construct a second linear relationship function between the strain and amplitude at the coating-removed position of each coated turbine blade.

[0010] Construct a third linear relationship function between the strain and amplitude at the corresponding maximum vibration stress position of the coated turbine blade at the working temperature based on the average value of the intercept and the average value of the slope of the second linear relationship function. , where is the average value of the slope of the second linear relationship function, is the average value of the intercept of the second linear relationship function, is the strain conversion coefficient, , where is the frequency of the coated turbine blade at the working temperature, is the frequency of the coated turbine blade at room temperature, is the material density of the coated turbine blade at the working temperature, is the material density of the coated turbine blade at room temperature, is the target test stress, is the elastic modulus of the material of the coated turbine blade at the working temperature, is the target test strain, is the elastic modulus of the material of the coated turbine blade at room temperature;

[0011] Analyze the amplitude required for the target test stress or target test strain at the working temperature according to the third linear relationship function, and conduct a high-cycle fatigue test on the coated turbine blade at the working temperature with the obtained amplitude to analyze and obtain the high-cycle fatigue strength of the coated turbine blade.

[0012] Furthermore, according to the vibration stress distribution test of multiple uncoated turbine blades of the same batch at room temperature, construct a first linear relationship function between the strain and amplitude at the maximum vibration stress position of each uncoated turbine blade, and calculate the average value of the intercept and the average value of the slope of multiple first linear relationship functions; if the relative deviation between the intercept of each second linear relationship function and the average value of the intercepts is greater than the first preset threshold, or the relative deviation between the slope of each second linear relationship function and the average value of the slopes is greater than the second preset threshold, then readjust the position of the strain gauge at the maximum vibration stress position of the coated turbine blade until the relative deviation between the intercept of each second linear relationship function and the average value of the intercepts is less than or equal to the first preset threshold, and the relative deviation between the slope of each second linear relationship function and the average value of the slopes is less than or equal to the second preset threshold.

[0013] Further, the values of the first preset threshold and the second preset threshold are both 1%.

[0014] Further, the method for determining the working temperature includes: determining the resonance points within the engine operating envelope according to the Campbell diagram of the uncoated turbine blade, and analyzing the blade vibration order corresponding to the resonance points; calculating the vibration stress distribution of the uncoated turbine blade at the corresponding vibration order by using the finite element method, and taking the temperature at the maximum vibration stress point as the working temperature.

[0015] Further, the method for removing the thermal barrier coating from the corresponding maximum vibration stress area on the coated turbine blade includes: removing the thermal barrier coating by sandblasting, wherein the sandblasting pressure is 0.2 MPa - 0.3 MPa, the sandblasting time for each area is 6 - 10 seconds, and the total time does not exceed 15 seconds.

[0016] To achieve the above technical effects, the present invention also provides a high-cycle fatigue strength analysis system for coated blades, which is used to implement the high-cycle fatigue strength analysis method for coated blades, and includes:

[0017] A data acquisition module, which is used to obtain the actual maximum vibration stress position of the uncoated turbine blade by respectively carrying out vibration stress distribution test data of multiple uncoated turbine blades of the same batch at room temperature on the vibration table in the way of using a clamping tenon.

[0018] A second model analysis module, which is used to test the strain and amplitude at the position where the thermal barrier coating is removed from the coated turbine blade at room temperature in the way of using a clamping tenon on the vibration table, and construct a second linear relationship function between the strain and amplitude at the position where the coating is removed from each coated turbine blade; the position where the coating is removed from the coated turbine blade is determined by the actual maximum vibration stress position of the uncoated turbine blade.

[0019] A third model analysis module, which is used to construct a third linear relationship function between the strain and amplitude at the corresponding maximum vibration stress position of the coated turbine blade at the working temperature according to the average value of the intercept and the average value of the slope of the second linear relationship function , where is the average value of the slope of the second linear relationship function, is the average value of the intercept of the second linear relationship function, is the strain conversion coefficient, , where is the frequency of the coated turbine blade at the working temperature, is the frequency of the coated turbine blade at room temperature, is the material density of the coated turbine blade at the working temperature, is the material density of the coated turbine blade at room temperature, is the target test stress, is the elastic modulus of the coated turbine blade material at the working temperature, is the target test strain, is the elastic modulus of the coated turbine blade material at room temperature;

[0020] The test parameter determination module is used to analyze and obtain the amplitude required for the target test stress or target test strain at the working temperature according to the third linear relationship function, so as to carry out the high-cycle fatigue test analysis of the coated turbine blade at the working temperature with the obtained amplitude to obtain the high-cycle fatigue strength of the coated turbine blade.

[0021] Further, in the second model analysis module, according to the vibration stress distribution test of multiple uncoated turbine blades of the same batch at room temperature, a first linear relationship function between the strain and the amplitude at the position of the maximum vibration stress of each uncoated turbine blade is constructed, and the average value of the intercepts and the average value of the slopes of multiple first linear relationship functions are calculated; if the relative deviation between the intercept of each second linear relationship function and the average value of the intercepts is greater than the first preset threshold, or the relative deviation between the slope of each second linear relationship function and the average value of the slopes is greater than the second preset threshold, then the position of the strain gauge is readjusted at the position of the maximum vibration stress of the coated turbine blade until the relative deviation between the intercept of each second linear relationship function and the average value of the intercepts is less than or equal to the first preset threshold, and the relative deviation between the slope of each second linear relationship function and the average value of the slopes is less than or equal to the second preset threshold.

[0022] Further, in the second model analysis module, the values of the first preset threshold and the second preset threshold are both 1%.

[0023] Further, in the third model analysis module and the test parameter determination module, the resonance points within the engine operating envelope are determined according to the Campbell diagram of the uncoated turbine blade, and the corresponding blade vibration orders of the resonance points are analyzed; the vibration stress distribution of the uncoated turbine blade at the corresponding vibration order is calculated by the finite element method, and the temperature at the point of the maximum vibration stress is used as the working temperature.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows: by constructing a third linear relationship function between the strain and the amplitude at the position of the maximum vibration stress of the coated turbine blade at the working temperature, the test amplitude for carrying out the high-cycle fatigue test of the coated turbine blade at the working temperature is obtained. The strength analysis test parameters determined in the strength analysis method of the present invention not only consider the influence of the coating on the vibration characteristics of the blade, but also ensure the accurate transition from the room temperature test data to the fatigue strength analysis at the working temperature through precise conversion coefficient adjustment, improve the reliability of the high-cycle fatigue strength of the coated turbine blade, and thus improve the reliability of the engine strength life design. Brief Description of the Drawings

[0025] Figure 1 It is the flowchart of the high-cycle fatigue strength analysis method for the coated blade in Embodiment 1;

[0026] Figure 2 It is the structural block diagram of the high-cycle fatigue strength analysis system for the coated blade in Embodiment 1;

[0027] Figure 3 It is the flowchart of the high-cycle fatigue strength analysis method for the coated blade in Embodiment 2;

[0028] Among them, 1. Data acquisition module; 2. Second model analysis module; 3. Third model analysis module; 4. Test parameter determination module. Specific implementation mode

[0029] The present invention will be further described in detail below in conjunction with the embodiments and the accompanying drawings. However, this should not be construed as limiting the scope of the above-mentioned subject matter of the present invention to the following embodiments. Any technology implemented based on the content of the present invention belongs to the scope of the present invention.

[0030] Embodiment 1

[0031] See Figure 1 and Figure 2 , a high-cycle fatigue strength analysis method for a coated blade, including:

[0032] Carry out vibration stress distribution tests on multiple uncoated turbine blades of the same batch at room temperature on a vibration table by using the clamping tenon method to obtain the actual maximum vibration stress position of the uncoated turbine blade;

[0033] Select multiple coated turbine blades of the same batch. According to the actual maximum vibration stress position of the uncoated turbine blade, remove the thermal barrier coating in the corresponding maximum vibration stress area on the coated turbine blade. Use the clamping tenon method to test the strain and amplitude at the position where the thermal barrier coating is removed from the coated turbine blade at room temperature, and construct a second linear relationship function between the strain and amplitude at the coating-removed position of each coated turbine blade;

[0034] According to the average value of the intercept and the average value of the slope of the second linear relationship function, construct a third linear relationship function between the strain and amplitude at the corresponding maximum vibration stress position of the coated turbine blade at the working temperature , where is the average value of the slope of the second linear relationship function, is the average value of the intercept of the second linear relationship function, is the strain conversion coefficient, , where is the frequency of the coated turbine blade at the working temperature, is the frequency of the coated turbine blade at room temperature, is the density of the coated turbine blade material at the working temperature, is the density of the coated turbine blade material at room temperature, is the target test stress, is the elastic modulus of the coated turbine blade material at the working temperature, is the target test strain, is the elastic modulus of the coated turbine blade material at room temperature;

[0035] According to the third linear relationship function, analyze the amplitude required for the target test stress or target test strain at the working temperature. Use the obtained amplitude to carry out the high-cycle fatigue test of the coated turbine blade at the working temperature, and analyze to obtain the high-cycle fatigue strength of the coated turbine blade.

[0036] In this embodiment, by obtaining the actual maximum vibration stress position of the uncoated turbine blade, after removing the coating at the corresponding position of the coated turbine blade, conduct a strain amplitude calibration test on the coated turbine blade to obtain the strain and amplitude at the position where the thermal barrier coating is removed from the coated turbine blade at room temperature. And use the strain amplitude calibration relationship function to construct the second linear relationship function of the strain and amplitude at the position where the thermal barrier coating is removed from the coated turbine blade, and then deduce the third linear relationship function of the strain and amplitude at the corresponding maximum vibration stress position of the coated turbine blade at the working temperature, so as to obtain the test amplitude for carrying out the high-cycle fatigue test of the coated turbine blade at the working temperature. The strength analysis test parameters determined in this embodiment not only consider the influence of the coating on the vibration characteristics of the blade, but also ensure the accurate transition from room temperature test data to fatigue strength analysis at the working temperature through precise conversion coefficient adjustment, improve the reliability of the high-cycle fatigue strength of the coated turbine blade, and thus improve the reliability of the engine strength life design, providing a scientific and efficient solution for the high-cycle fatigue strength evaluation of the coated turbine blade.

[0037] Based on the same inventive concept, this embodiment also provides a high-cycle fatigue strength analysis system for coated blades, used to implement the high-cycle fatigue strength analysis method for coated blades, including:

[0038] The data acquisition module 1 is used to obtain the actual maximum vibration stress position of the uncoated turbine blade according to the vibration stress distribution test data of multiple uncoated turbine blades of the same batch at room temperature by using the clamping tenon on the vibration table;

[0039] The second model analysis module 2 is used to test the strain and amplitude at the position where the thermal barrier coating is removed from the coated turbine blade at room temperature by using the clamping tenon on the vibration table, and construct the second linear relationship function between the strain and amplitude at the position where the coating is removed from each coated turbine blade; the position where the coating is removed from the coated turbine blade is determined by the actual maximum vibration stress position of the uncoated turbine blade;

[0040] The third model analysis module 3 is configured to construct a third linear relationship function between the strain and amplitude at the position of the maximum vibration stress of the coated turbine blade at the working temperature according to the average intercept and the average slope of the second linear relationship function , where is the average slope of the second linear relationship function, is the average intercept of the second linear relationship function, is the strain conversion coefficient, , where is the frequency of the coated turbine blade at the working temperature, is the frequency of the coated turbine blade at room temperature, is the material density of the coated turbine blade at the working temperature, is the material density of the coated turbine blade at room temperature, is the target test stress, is the elastic modulus of the material of the coated turbine blade at the working temperature, is the target test strain, is the elastic modulus of the material of the coated turbine blade at room temperature;

[0041] The test parameter determination module 4 is configured to analyze the amplitude required for the target test stress or the target test strain at the working temperature according to the third linear relationship function, so as to carry out a high-cycle fatigue test analysis of the coated turbine blade at the working temperature with the obtained amplitude to obtain the high-cycle fatigue strength of the coated turbine blade.

[0042] Example 2

[0043] See Figure 3 , in this example, taking the strength analysis of a certain type of coated turbine blade as an example, the process of the high-cycle fatigue strength analysis method of the coated blade of the present invention is described in detail, and the specific operation process is as follows:

[0044] Step 1: Use the clamping tenon method to carry out vibration stress distribution tests on multiple uncoated turbine blades of the same batch at room temperature on a vibration table, and obtain the actual position of the maximum vibration stress of the uncoated turbine blade;

[0045] Step 2: Construct a first linear relationship function between the strain and amplitude at the position of the maximum vibration stress of each uncoated turbine blade, and calculate the average intercept and the average slope of the multiple first linear relationship functions;

[0046] Step 3: Select multiple coated turbine blades of the same batch. According to the actual maximum vibration stress position of the uncoated turbine blade, remove the thermal barrier coating from the corresponding maximum vibration stress area on the coated turbine blade. Use the clamping tenon method to test the strain and amplitude at the position where the thermal barrier coating is removed from the coated turbine blade at room temperature on the vibration table, and construct the second linear relationship function between the strain and amplitude at the coating-removed position of each coated turbine blade;

[0047] In this embodiment, the method for removing the thermal barrier coating from the corresponding maximum vibration stress area on the coated turbine blade includes: removing the thermal barrier coating by sandblasting process, where the sandblasting pressure is 0.2 MPa - 0.3 MPa, the sandblasting time for each area is 6 - 10 seconds, and the total time does not exceed 15 seconds.

[0048] Step 4: Determine that the relative deviation between the intercept of each second linear relationship function and the average value of the intercepts is less than or equal to the first preset threshold, and the relative deviation between the slope of each second linear relationship function and the average value of the slopes is less than or equal to the second preset threshold;

[0049] In this embodiment, if the relative deviation between the intercept of each second linear relationship function and the average value of the intercepts is greater than the first preset threshold, or the relative deviation between the slope of each second linear relationship function and the average value of the slopes is greater than the second preset threshold, then readjust the position of the strain gauge at the maximum vibration stress position of the coated turbine blade until the relative deviation between the intercept of each second linear relationship function and the average value of the intercepts is less than or equal to the first preset threshold, and the relative deviation between the slope of each second linear relationship function and the average value of the slopes is less than or equal to the second preset threshold. After confirming that the second linear relationship function meets the preset conditions, the required amplitude can be determined according to this second linear relationship function in combination with the target test stress or target test strain. This method can fully consider the influence of the coating on the vibration characteristics of the blade, thereby improving the accuracy of the high-cycle fatigue strength analysis.

[0050] In this embodiment, the values of the first preset threshold and the second preset threshold are both 1%. In some other embodiments, the first preset threshold and the second preset threshold can be reasonably determined according to the design requirements of specific turbine blades.

[0051] Step 5: Construct the third linear relationship function between the strain and amplitude at the corresponding maximum vibration stress position of the coated turbine blade at the working temperature according to the average value of the intercepts and the average value of the slopes of the second linear relationship function , where is the average value of the slopes of the second linear relationship function, is the average value of the intercepts of the second linear relationship function, is the strain conversion coefficient, , where is the frequency of the coated turbine blade at the operating temperature, is the frequency of the coated turbine blade at room temperature, is the material density of the coated turbine blade at the operating temperature, is the material density of the coated turbine blade at room temperature, is the target test stress, is the elastic modulus of the material of the coated turbine blade at the operating temperature, is the target test strain, is the elastic modulus of the material of the coated turbine blade at room temperature;

[0052] Step Six: Analyze the amplitude required for the target test stress or target test strain at the operating temperature according to the third linear relationship function, and conduct a high-cycle fatigue test on the coated turbine blade at the operating temperature using the obtained amplitude to analyze and obtain the high-cycle fatigue strength of the coated turbine blade.

[0053] The method for determining the operating temperature in this embodiment includes: determining the resonance points within the engine operating envelope according to the Campbell diagram of the uncoated turbine blade, and analyzing the blade vibration order corresponding to the resonance points; calculating the vibration stress distribution of the uncoated turbine blade at the corresponding vibration order using the finite element method, and taking the temperature at the maximum vibration stress point as the operating temperature. This operating temperature can reflect the maximum stress state that the blade may suffer in the actual working environment, thereby ensuring that the performance of the coated turbine blade under extreme conditions can be obtained in the subsequent high-cycle fatigue test.

[0054] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for analyzing the high-cycle fatigue strength of a coated blade, characterized in that Including: By using the method of clamping tenons, vibration stress distribution tests of multiple uncoated turbine blades of the same batch are carried out on a shaker at room temperature to obtain the actual maximum vibration stress position of the uncoated turbine blades; Select multiple coated turbine blades of the same batch. According to the actual maximum vibration stress position of the uncoated turbine blades, remove the thermal barrier coating in the corresponding maximum vibration stress area on the coated turbine blades. Use the method of clamping tenons to test the strain and amplitude at the position where the thermal barrier coating is removed from the coated turbine blades on the shaker at room temperature, and construct the second linear relationship function between the strain and amplitude at the coating removal position of each coated turbine blade; Construct a third linear relationship function between the strain and amplitude at the position of the maximum vibration stress of the coated turbine blade at the working temperature according to the average intercept and average slope of the second linear relationship function. , where is the average slope of the second linear relationship function, is the average intercept of the second linear relationship function, is the strain conversion coefficient, , where is the frequency of the coated turbine blade at the working temperature, is the frequency of the coated turbine blade at room temperature, is the material density of the coated turbine blade at the working temperature, is the material density of the coated turbine blade at room temperature, is the target test stress, is the elastic modulus of the material of the coated turbine blade at the working temperature, is the target test strain, is the elastic modulus of the material of the coated turbine blade at room temperature; According to the third linear relationship function, analyze and obtain the amplitude required for the target test stress or target test strain at the working temperature. Use the obtained amplitude to carry out the high-cycle fatigue test of the coated turbine blade at the working temperature, and analyze and obtain the high-cycle fatigue strength of the coated turbine blade.

2. The high-cycle fatigue strength analysis method of the coated blade according to claim 1, characterized in that, According to the vibration stress distribution test of multiple uncoated turbine blades of the same batch at room temperature, construct the first linear relationship function between the strain and amplitude at the maximum vibration stress position of each uncoated turbine blade, and calculate the average intercept and average slope of multiple first linear relationship functions; If the relative deviation between the intercept of each second linear relationship function and the average intercept is greater than the first preset threshold, or the relative deviation between the slope of each second linear relationship function and the average slope is greater than the second preset threshold, then readjust the position of the strain gauge at the maximum vibration stress position of the coated turbine blade until the relative deviation between the intercept of each second linear relationship function and the average intercept is less than or equal to the first preset threshold, and the relative deviation between the slope of each second linear relationship function and the average slope is less than or equal to the second preset threshold.

3. The high-cycle fatigue strength analysis method of the coated blade according to claim 2, wherein The values of both the first preset threshold and the second preset threshold are 1%.

4. The method for analyzing the high-cycle fatigue strength of a coated blade according to claim 1, wherein The determination method of the working temperature includes: determining the resonance points within the engine operating envelope according to the Campbell diagram of the uncoated turbine blades, and analyzing the blade vibration order corresponding to the resonance points; using the finite element method to calculate the vibration stress distribution of the uncoated turbine blades at the corresponding vibration order, and taking the temperature of the maximum vibration stress point as the working temperature.

5. The high-cycle fatigue strength analysis method for coated blades according to claim 1, characterized in that The method for removing the thermal barrier coating in the corresponding maximum vibration stress area on the coated turbine blade includes: removing the thermal barrier coating by sandblasting process, where the sandblasting pressure is 0.2 MPa - 0.3 MPa, the sandblasting time for each area is 6 - 10 seconds, and the total time does not exceed 15 seconds.

6. A high-cycle fatigue strength analysis system for coated blades, which is used to implement the high-cycle fatigue strength analysis method for coated blades according to any one of claims 1-5, and is characterized in that, Including: The data acquisition module is used to obtain the actual maximum vibration stress position of the uncoated turbine blades according to the vibration stress distribution test data of multiple uncoated turbine blades of the same batch carried out on a shaker by using the method of clamping tenons; The second model analysis module is used to construct the second linear relationship function between the strain and amplitude at the position where the thermal barrier coating is removed from the coated turbine blades tested on the shaker at room temperature by using the method of clamping tenons; the coating removal position of the coated turbine blade is determined by the actual maximum vibration stress position of the uncoated turbine blade; The third model analysis module is used to construct a third linear relationship function between the strain and amplitude at the position of the maximum vibration stress of the coated turbine blade at the working temperature according to the average intercept and average slope of the second linear relationship function. , where is the average slope of the second linear relationship function, is the average intercept of the second linear relationship function, is the strain conversion coefficient, , where is the frequency of the coated turbine blade at the working temperature, is the frequency of the coated turbine blade at room temperature, is the material density of the coated turbine blade at the working temperature, is the material density of the coated turbine blade at room temperature, is the target test stress, is the elastic modulus of the material of the coated turbine blade at the working temperature, is the target test strain, is the elastic modulus of the material of the coated turbine blade at room temperature; A test parameter determination module, which is used to analyze and obtain the amplitude required for the target test stress or target test strain at the working temperature according to the third linear relationship function, so as to carry out a high-cycle fatigue test analysis of the coated turbine blade at the working temperature with the obtained amplitude to obtain the high-cycle fatigue strength of the coated turbine blade.

7. The high-cycle fatigue strength analysis system for coated blades according to claim 6, wherein In the second model analysis module, according to the vibration stress distribution test of multiple uncoated turbine blades of the same batch at room temperature, a first linear relationship function between the strain at the maximum vibration stress position and the amplitude of each uncoated turbine blade is constructed, and the average value of the intercepts and the average value of the slopes of multiple first linear relationship functions are calculated; If the relative deviation between the intercept of each second linear relationship function and the average value of the intercepts is greater than the first preset threshold, or the relative deviation between the slope of each second linear relationship function and the average value of the slopes is greater than the second preset threshold, then the position of the strain gauge is readjusted at the maximum vibration stress position of the coated turbine blade until the relative deviation between the intercept of each second linear relationship function and the average value of the intercepts is less than or equal to the first preset threshold, and the relative deviation between the slope of each second linear relationship function and the average value of the slopes is less than or equal to the second preset threshold.

8. The high-cycle fatigue strength analysis system for coated blades according to claim 7, characterized in that In the second model analysis module, the values of the first preset threshold and the second preset threshold are both 1%.

9. The high-cycle fatigue strength analysis system for coated blades according to claim 6, wherein In the third model analysis module and the test parameter determination module, the resonance points within the engine operating envelope are determined according to the Campbell diagram of the uncoated turbine blade, and the blade vibration order corresponding to the resonance points is analyzed; The vibration stress distribution of the uncoated turbine blade at the corresponding vibration order is calculated by using the finite element method, and the temperature at the maximum vibration stress point is used as the working temperature.

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