In-situ mechanical test system and method for aero-engine turbine blade material

Abstract

The invention discloses an aero-engine turbine blade material in-situ mechanical test system and method, and the system comprises a multi-axis loading unit which is used for simulating the multi-axis stress state of a turbine blade under an actual working condition; the high-temperature environment module is used for realizing local rapid heating of the sample; the in-situ observation system integrates a high-temperature microscope lens with a long working distance and a high-speed camera and is used for observing and recording microscopic damage evolution of the turbine blade sample in a high-temperature loading process in real time; and the control unit is internally provided with a temperature-stress decoupling control model and a microdefect identification model and is used for compensating the plastic deformation heat effect in real time and quantifying the damage factor D. Synchronous loading of centrifugal force is achieved through the three-axis servo actuator, composite stress is accurately reproduced, the load error is small, and the limitation that a traditional single-axis test cannot simulate the multi-source load of the blade is broken through. Meanwhile, plastic work-induced temperature rise interference is reduced, and the technical problem of data distortion caused by temperature drift in a high-temperature test is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aerospace alloy material performance testing, in particular, relates to a turbine blade material in-situ mechanical testing system and method for an aero-engine. BACKGROUND

[0002] As a core component of an aircraft, the performance of an aero-engine directly relates to the flight performance and safety of the aircraft. Turbine blades, as one of the key hot-end components of an aero-engine, work under extreme conditions such as high temperature, high pressure, and high speed, and need to withstand multiple loads such as centrifugal force, aerodynamic force, and thermal cycling. Therefore, the material performance of turbine blades is crucial for the performance and reliability of the engine.

[0003] Traditional mechanical testing methods, such as uniaxial tension or compression testing, can provide basic mechanical property data of materials, but have the following limitations:

[0004] Uniaxial testing is dominant: a universal testing machine can only simulate a single tensile or compressive load and cannot reproduce the multi-axial stress state of turbine blades in actual work. This single-load testing method cannot fully evaluate the performance of materials under actual working conditions, which may lead to misjudgment of material performance.

[0005] High-temperature environment distortion: existing high-temperature testing equipment, such as resistance high-temperature furnaces, has a large temperature gradient during heating, which cannot guarantee the temperature uniformity of the sample under high-temperature environment. In addition, these devices cannot simultaneously apply complex loads such as centrifugal force and aerodynamic force, resulting in a deviation between the test results and the actual working conditions, affecting the accuracy of the test results.

[0006] Damage observation is missing: existing testing equipment cannot capture the micro-damage evolution of materials, such as creep cavitation and crack initiation, in real time during high-temperature loading. The evolution of these micro-damages is crucial for understanding the failure mechanism of materials, but traditional testing methods often cannot provide this information.

[0007] Therefore, developing a testing system that can simulate the actual working conditions of turbine blades and simultaneously observe the micro-damage evolution of materials in real time is of great significance for improving the performance and reliability of turbine blades of aero-engines. SUMMARY

[0008] The present application provides an aero-engine turbine blade material in-situ mechanical testing method, which solves the technical problem of deviation between the test results of the existing turbine blade material performance testing method and the actual situation and the inability to provide failure mechanism information.

[0009] The present application is achieved by the following solutions:

[0010] An aero-engine turbine blade material in-situ mechanical testing system, comprising:

[0011] Multi-axis loading unit: three-axis independent servo actuators are used to realize axial, radial and torsional loading respectively, simulating the multi-axis stress state of turbine blade under actual working conditions;

[0012] High temperature environment module: used to realize local rapid heating of the sample by using a high frequency induction coil combined with a heat shield for temperature loading of the turbine blade sample;

[0013] In-situ observation system: long working distance high temperature microscope and high speed camera are integrated to observe and record the micro damage evolution of the turbine blade sample in real time through the quartz observation window during the high temperature loading process;

[0014] The control unit is provided with a temperature-stress decoupling control model and a micro defect identification model, which is used to compensate the plastic deformation thermal effect in real time and quantify the damage factor D.

[0015] Further, the axial loading of the multi-axis loading unit is ±50kN, the radial loading is ±30kN, the torsional loading is ±200Nm, the frequency range is 0-100Hz, and the accuracy reaches ±0.1%FS.

[0016] Further, the frequency of the high frequency induction coil of the high temperature environment module is above 200kHz, the heat shield material is ZrO2, and the heating temperature reaches 1100℃±5℃.

[0017] Further, the magnification of the long working distance high temperature microscope is above 1000 times, and the frame rate of the high speed camera is above 5000fps.

[0018] Another aspect of the present application also provides an aero-engine turbine blade material in-situ mechanical testing method, based on the aero-engine turbine blade material in-situ mechanical testing system, comprising the steps of:

[0019] S1, loading and heating synchronization: start the multi-axis loading unit and the high temperature environment module, load and heat according to the pre-set loading parameters and heating program, gradually apply the combined load of axial, radial and torsional, and heat the sample to the target temperature, monitor the stress and temperature changes of the sample in real time during the loading and heating process, and ensure the synchronization and stability of the loading and heating;

[0020] S2, in-situ observation and data collection: during multi-axial combined load loading and heating, the high-temperature microscope lens and high-speed camera of the in-situ observation system continuously shoot images of the sample surface, capture the dynamic changes of micro-damage, record the micro-damage evolution of the sample surface in real time, including the formation of creep cavities, the initiation and propagation of cracks, and at the same time, collect the stress, temperature and damage image data of the sample, which provides detailed information for subsequent analysis;

[0021] S3, temperature-stress decoupling control: using the temperature-stress decoupling control model, the inductive heating power and the plastic deformation rate of the sample are monitored in real time, the inductive heating power is dynamically corrected according to the temperature-stress decoupling control model, the plastic deformation thermal effect is compensated, the temperature of the sample is kept in the target temperature range, and the accurate control of the temperature of the sample is ensured;

[0022] S4, damage quantification analysis: through the micro-defect identification model, the collected damage image data is analyzed and quantified in real time, the micro-defects in the image are automatically identified, including cavities and cracks, and their areas are calculated; according to the damage factor formula, the damage factor D is calculated in real time to evaluate the damage degree of the sample in the high-temperature loading process; the change trend of the damage factor is used to judge the damage development process and critical point of the sample, which provides an important basis for material performance evaluation and failure analysis;

[0023] S5, data processing and analysis: including stress-strain relationship analysis, temperature distribution and damage correlation analysis, damage evolution process analysis, performance evaluation and optimization suggestion;

[0024] S6, test result verification: including comparison with actual working conditions, comparison with existing standards and literature, and repeatability test.

[0025] Further, in step S1, the high-temperature PST titanium aluminum single crystal used for aero-engine turbine blade is selected as the test material, and after the shape and size of the sample are processed according to the requirements, the surface of the sample needs to be finished to reduce the influence of surface defects on the test results;

[0026] The target temperature is 1100℃±5℃.

[0027] Further, in step S3:

[0028] The temperature-stress decoupling control model is:

[0029]

[0030] Where, T actual is the actual temperature, P induction is the inductive heating power, is the plastic deformation rate, and k1 and k2 are compensation coefficients.

[0031] Further, in step S4:

[0032] By using the YOLOv5 micro-defect recognition model, the collected damage image data is analyzed and quantified in real time, and the micro-defects in the image, including voids and cracks, are automatically recognized and their areas are calculated.

[0033] The calculation formula of damage factor D is: D = ∑void area / observation area.

[0034] Further, in step S5:

[0035] The stress-strain relationship analysis specifically includes: processing the collected stress and strain data, drawing the stress-strain curve, analyzing the mechanical behavior of the sample under multi-axial combined load, evaluating the strength and toughness of the sample through the characteristic points of the curve, including yield point and fracture point, comparing the stress-strain relationship under different loading paths, and studying the influence of multi-axial stress state on the mechanical properties of the sample.

[0036] The temperature distribution and damage correlation analysis specifically includes: combining temperature data and damage images to analyze the relationship between temperature distribution and micro-damage of the sample under high temperature environment, study the influence of temperature gradient on micro-damage evolution, determine the damage difference between high temperature region and low temperature region, and reveal the influence mechanism of temperature field inhomogeneity on material performance through temperature-damage correlation analysis.

[0037] The damage evolution process analysis specifically includes: analyzing the damage image sequence collected by the in-situ observation system, reconstructing the micro-damage evolution process of the sample during high temperature loading, determining the initiation, development and expansion law of micro-damage through image comparison and damage factor change trend, and analyzing the formation mechanism of different damage modes, such as the relationship between the formation of creep voids and the initiation and expansion of cracks.

[0038] Performance evaluation and optimization suggestion specifically includes: comprehensively evaluating the performance of high-temperature alloy under actual service conditions by integrating mechanical property data, temperature distribution data and micro-damage evolution information, and proposing optimization suggestions for material performance according to test results, including improving alloy composition, adjusting processing technology or optimizing loading conditions, providing scientific basis for the design and manufacture of aero-engine turbine blade, and improving its reliability and service life.

[0039] Further, in step S6:

[0040] The comparison with actual working conditions specifically includes: comparing and verifying the test results with the stress state, temperature distribution and damage mode of aero-engine turbine blade in actual service, verifying the effectiveness and reliability of the test method through comparative analysis, and ensuring that the test results can accurately reflect the performance of the material under actual working conditions.

[0041] Compared with existing standards and literature, it includes: comparing test results with existing material performance standards and related literature, verifying the accuracy and consistency of the test method, ensuring that the test results meet industry standards and academic consensus through comparative analysis, and providing reliable reference for material performance evaluation;

[0042] Repeatability test specifically includes: repeated testing of the same material to verify the repeatability and stability of the test method, evaluating the dispersion and reliability of the test results through statistical analysis, and ensuring that the test method can stably provide consistent test results to provide reliable experimental data support for material performance research.

[0043] Compared with the prior art, the present application has the following beneficial effects:

[0044] The present application provides an aero-engine turbine blade material in-situ mechanical testing system and method. The present application realizes synchronous loading of centrifugal force (axial), aerodynamic force (radial) and torque (torsion) through a three-axis servo actuator, accurately reproduces composite stress, and the load error is <±0.1% FS, which breaks through the limitation of traditional single-axis test that cannot simulate multi-source load of the blade. At the same time, the present application realizes thermal-force dynamic decoupling control, and corrects the heating power in real time through the plastic deformation rate, reduces the plastic work-induced temperature rise interference (temperature drift control within ±3℃), and solves the technical problem of data distortion caused by temperature drift in high-temperature test.

[0045] In addition to the purposes, features and advantages described above, the present application has other purposes, features and advantages. The present application will be further described in detail below with reference to the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0046] The drawings incorporated into the specification and forming part of the specification, show embodiments consistent with the present application, and together with the specification, serve to explain the principles of the present application.

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows. Obviously, for those skilled in the art, other drawings can also be obtained without creative labor based on these drawings:

[0048] Figure 1 is a schematic diagram of the aero-engine turbine blade material in-situ mechanical testing system of the preferred embodiment of the present application;

[0049] Figure 2 is a schematic diagram of the YOLOv5 model identification flowchart of the preferred embodiment of the present application;

[0050] Figure 3Figure 1 is a schematic diagram of a method for in-situ mechanical testing of turbine blade materials of an aero-engine according to an embodiment of the present application;

[0051] Figure 4 Figure 2 is a schematic diagram of a module for in-situ mechanical testing of turbine blade materials of an aero-engine according to an embodiment of the present application;

[0052] Figure 5 Figure 3 is a schematic diagram of an electronic device according to an embodiment of the present application;

[0053] Figure 6 Figure 4 is a diagram of the internal structure of a computer device according to an embodiment of the present application. DETAILED DESCRIPTION

[0054] It should be understood that the specific embodiments described herein are merely intended to explain the technical solutions of the present application and are not intended to limit the present application.

[0055] In order to better understand the technical solutions of the present application, the following will be described in detail in conjunction with the accompanying drawings and specific embodiments.

[0056] In the following embodiments, high-temperature PST titanium aluminum single crystals for turbine blades of an aero-engine are selected as test materials to ensure their representativeness and typicality.

[0057] Sample preparation

[0058] The titanium aluminum single crystal is processed into a dumbbell-shaped sample by wire cutting technology, and the gauge section has a size of 15 mm in length, 3 mm in width, and 1.5 mm in thickness. M6 threaded interfaces are processed at both ends of the sample for clamping with a multi-axis clamp. The sample is treated in a mixed electrolyte (perchloric acid: ethanol = 1:9) at a voltage of 20 V for 30 s to eliminate the surface work hardening layer. Fluorescent marker points for in-situ image displacement tracking in a high-temperature environment are sprayed on the observation area of the sample. The marker points are ZrO2 particles with a diameter of 0.1 μm, which serve as reference points for in-situ image displacement tracking.

[0059] The sample crystal orientation deviation is confirmed to be ≤2° by EBSD (electron backscatter diffraction) to ensure that the crystal orientation conforms to the actual service state of the blade.

[0060] As shown in Figure 1 The preferred embodiment of the present application provides an in-situ mechanical testing system for turbine blade materials of an aero-engine, which comprises:

[0061] Multi-axis loading unit: three-axis independent servo actuators are adopted to realize axial, radial and torsional loading respectively, to simulate the combined stress state of centrifugal force and aerodynamic load that the blade is subjected to in actual work, such as axial load of the multi-axis loading unit +40kN (tension) / -35kN (compression), radial load: ±25kN, torque ±180Nm, frequency 80Hz (simulating engine speed 12,000rpm).

[0062] Calibrate the load accuracy (±0.08% FS) by laser displacement sensor;

[0063] High-temperature environment module: used to realize local rapid heating of the sample by using a high-frequency induction coil combined with a heat shield for temperature loading of the turbine blade sample;

[0064] In-situ observation system: long working distance high temperature microscope lens and high speed camera are integrated to observe and record the micro damage evolution of the turbine blade sample in real time through the quartz observation window during high temperature loading;

[0065] Control unit, built-in temperature-stress decoupling control model and micro defect identification model, for real-time compensation of plastic deformation thermal effect and quantification of damage factor D.

[0066] Compared with the traditional scheme, the embodiment has the following significant technical effects:

[0067] Temperature uniformity: through high-frequency induction heating, the temperature uniformity of the sample is improved from ±30℃ of the traditional resistance furnace to ±5℃, effectively avoiding data distortion caused by local softening of the material.

[0068] Load dimension: three-axis independent control is realized, which can accurately simulate the complex stress state of the turbine blade, while the traditional scheme can only realize single-axis loading.

[0069] Damage resolution: through the in-situ dynamic observation system, the damage resolution is improved from ≥1μm of the traditional post-mortem metallographic observation to 0.1μm, which can capture the creep crack initiation critical point.

[0070] Test efficiency: through multi-axis synchronous loading, the single test time is shortened from ≥24h of the traditional scheme to ≤8h, which significantly improves the test efficiency and shortens the research and development cycle by 60%.

[0071] Preferably, the axial loading of the multi-axis loading unit is ±50kN, the radial loading is ±30kN, the torsional loading is ±200Nm, the frequency range is 0-100Hz, and the accuracy reaches ±0.1% FS.

[0072] Preferably, the frequency of the high-frequency induction coil of the high-temperature environment module is above 200 kHz, the heat shield material is ZrO2, the heating temperature reaches 1100℃±5℃, and the high-temperature environment module is used for rapid local heating of the sample, while avoiding premature failure of the sample due to grain boundary sliding, the induction coil frequency is 200 kHz, the target temperature is set to the service temperature of the PST titanium aluminum single crystal (1100℃±5℃), and the temperature rising rate is 200℃ / s.

[0073] Preferably, the magnification of the long-working-distance high-temperature microscope lens is above 1000 times, the frame rate of the high-speed camera is above 5000 fps, and the observation area is a 2mm×2mm range at the center of the gauge length section, which can capture the 0.1μm level of creep cavity initiation.

[0074] Referring to Figure 2 , the control unit is built-in temperature-stress decoupling control model and micro defect recognition model based on YOLOv5, which is used for real-time compensation of plastic deformation heat effect and quantification of damage factor D, damage factor D = ∑cavity area / observation area.

[0075] As Figure 3 shown, another preferred embodiment of the present application also provides an aero-engine turbine blade material in-situ mechanical testing method, based on the aero-engine turbine blade material in-situ mechanical testing system, comprising the steps of:

[0076] S1, loading and heating synchronization: start the multi-axis loading unit and the high-temperature environment module, load and heat according to the pre-set loading parameters and heating program, gradually apply the combined load of axial, radial and torsional, and heat the sample to the target temperature, monitor the stress and temperature changes of the sample in real time during the loading and heating process, and ensure the synchronization and stability of the loading and heating;

[0077] S2, in-situ observation and data acquisition: during the multi-axis combined load loading and heating, the high-temperature microscope lens and high-speed camera of the in-situ observation system continuously shoot the image of the sample surface, capture the dynamic changes of micro damage, record the micro damage evolution of the sample surface in real time, including the formation of creep cavity, the initiation and expansion of crack, at the same time, collect the stress, temperature and damage image data of the sample, and provide detailed information for subsequent analysis;

[0078] S3, temperature-stress decoupling control: use the temperature-stress decoupling control model to monitor the induction heating power and the plastic deformation rate of the sample in real time, dynamically correct the induction heating power according to the temperature-stress decoupling control model, compensate the plastic deformation heat effect, keep the sample temperature in the target temperature range, and ensure the accurate control of the sample temperature;

[0079] S4, damage quantification analysis: through the micro defect identification model, the collected damage image data is analyzed and quantified in real time, the micro defects in the image are automatically identified, including holes and cracks, and the areas thereof are calculated; according to the damage factor formula, the damage factor D is calculated in real time, the damage degree of the sample in the high temperature loading process is evaluated, and the change trend of the damage factor is used to judge the damage development process and critical point of the sample, which provides an important basis for material performance evaluation and failure analysis;

[0080] S5, data processing and analysis: including stress-strain relationship analysis, temperature distribution and damage correlation analysis, damage evolution process analysis, performance evaluation and optimization suggestion;

[0081] S6, test result verification: including comparison with actual working conditions, comparison with existing standards and literature, and repetitive test.

[0082] The embodiment provides an in-situ mechanical test method for turbine blade materials of an aero-engine, through the test method, the multiaxial composite load and high temperature environment of the nickel-based high-temperature alloy for the turbine blade of the aero-engine in actual service can be comprehensively and accurately simulated, the micro damage evolution of the material is observed in real time, scientific basis is provided for material performance evaluation and failure analysis, and important technical support is provided for the design and manufacturing of the turbine blade of the aero-engine.

[0083] Preferably, in step S1, the sample selects a high-temperature PST titanium aluminum single crystal for a turbine blade of an aero-engine as test material, after the shape and size of the sample are processed according to requirements, the surface of the sample needs to be finished to reduce the influence of surface defects on the test result;

[0084] The target temperature is 1100℃±5℃.

[0085] Preferably, in step S3:

[0086] The temperature-stress decoupling control model is:

[0087]

[0088] Wherein, T actual is the actual temperature, P induction is the induction heating power, is the plastic deformation rate, and k1 and k2 are compensation coefficients.

[0089] Preferably, in step S4:

[0090] Through the micro defect identification model based on YOLOv5, the collected damage image data is analyzed and quantified in real time, the micro defects in the image are automatically identified, including holes and cracks, and the areas thereof are calculated;

[0091] The damage factor D is calculated by the formula: D = ∑cavity area / observation area.

[0092] Preferably, in step S5:

[0093] The stress-strain relationship analysis specifically includes: processing the collected stress and strain data, drawing the stress-strain curve, analyzing the mechanical behavior of the sample under multi-axial complex load, evaluating the strength and toughness of the sample through the characteristic points of the curve, including the yield point and the fracture point, comparing the stress-strain relationship under different loading paths, and studying the influence of multi-axial stress state on the mechanical properties of the sample;

[0094] The temperature distribution and damage correlation analysis specifically includes: combining temperature data and damage images to analyze the relationship between temperature distribution and micro-damage of the sample under high temperature environment, studying the influence of temperature gradient on micro-damage evolution, determining the damage difference between high temperature region and low temperature region, and revealing the influence mechanism of temperature field inhomogeneity on material performance through temperature-damage correlation analysis;

[0095] The damage evolution process analysis specifically includes: analyzing the damage image sequence collected by the in-situ observation system, reconstructing the micro-damage evolution process of the sample during high temperature loading, determining the initiation, development and expansion law of micro-damage through image comparison and damage factor trend, and analyzing the formation mechanism of different damage modes, such as the relationship between the formation of creep cavity and the initiation and expansion of cracks;

[0096] The performance evaluation and optimization suggestion specifically includes: comprehensively evaluating the performance of high-temperature alloy under actual service conditions by integrating mechanical property data, temperature distribution data and micro-damage evolution information, and proposing optimization suggestions for material performance according to test results, including improving alloy composition, adjusting processing technology or optimizing loading conditions, providing scientific basis for the design and manufacture of aircraft engine turbine blades, and improving their reliability and service life.

[0097] Preferably, in step S6:

[0098] The comparison with actual working conditions specifically includes: comparing and verifying the test results with the stress state, temperature distribution and damage mode of the aircraft engine turbine blade in actual service, verifying the effectiveness and reliability of the test method through comparative analysis, and ensuring that the test results can accurately reflect the performance of the material under actual working conditions;

[0099] The comparison with existing standards and literature specifically includes: comparing the test results with existing material performance standards and related literature to verify the accuracy and consistency of the test method, ensuring that the test results meet industry standards and academic consensus through comparative analysis, and providing reliable reference for material performance evaluation;

[0100] The repeatability test specifically includes: performing multiple repeated tests on the same material, verifying the repeatability and stability of the test method, evaluating the dispersion and reliability of the test results through statistical analysis, and ensuring that the test method can stably provide consistent test results to provide reliable experimental data support for material performance research.

[0101] The in-situ mechanical testing process of the turbine blade material of the aero-engine is exemplarily illustrated below through specific embodiments.

[0102] The test procedure is as follows:

[0103] Synchronous loading and heating:

[0104] Based on the high-temperature environment module, the specimen is heated at a rate of 200℃ / s until it reaches 1100℃, and the temperature is fed back in real time by a dual-color infrared temperature meter. The PID algorithm controls the fluctuation within ±3℃. At the same time, the specimen is subjected to combined loads, specifically axial +40kN, radial +25kN, and torque +180Nm, to simulate the stress state under the take-off working condition of the aircraft.

[0105] In-situ observation and data collection:

[0106] Under the conditions of multi-axial combined load and heating, the high-temperature microscope lens and high-speed camera of the in-situ observation system continuously capture images of the specimen surface, capture the dynamic changes of micro-damage, and record the micro-damage evolution of the specimen surface in real time, including the formation of creep cavities, the initiation and propagation of cracks. At the same time, the stress, temperature, and damage image data of the specimen are collected to provide detailed information for subsequent analysis;

[0107] Temperature-stress decoupling control:

[0108] When the plastic deformation rate ε plastic >5×10 -5 s -1 , the decoupling model is triggered: T=0.75P-1.2ε plastic +28 (where the coefficients κ1=0.75 and κ2=-1.2 are determined through pre-calibration), and the induced power is automatically reduced by 5%, thereby inhibiting the temperature rise of the specimen and maintaining temperature stability.

[0109] In-situ damage quantification:

[0110] YOLOv5 model identification process: the high-speed camera collects images of the specimen observation area at 0.2ms per frame; the YOLOv5 model is used to segment and identify the cavities and cracks in the images, with a confidence level of >95% (500 sets of SEM labeled images are used for training, and the test set recognition accuracy is 98.7%, with a cavity area measurement error of <5%); the area S_i of a single cavity is calculated.

[0111] The calculation formula of damage factor D is D = ∑S_i / 4mm 2 (The observation area is 2mm x 2mm).

[0112] The critical point warning value is set as D≥0.03, and when the damage factor exceeds the critical point, the warning is triggered.

[0113] Typical damage evolution data are shown in Table 1:

[0114] Table 1- Typical damage evolution data table

[0115] Time (min) 0 30 120 180 (critical point) Damage factor D 0 0.008 0.019 0.032 Damage type - Microvoids Void coalescence Crack initiation

[0116] Results verification:

[0117] 1. Comparison with actual working conditions

[0118] Through the test, it is found that the crack initiation position of the blade in the service process is consistent with the observation area of the test, and is located in the stress concentration area of the middle of the blade body.

[0119] 2. Reproducibility verification

[0120] Table 2- Reproducibility verification test result table

[0121] Test batch 1 2 3 RSD (relative standard deviation) Critical time (min) 178 182 180 ≤1.5％ D critical value 0.031 0.033 0.032 ≤3％

[0122] Data analysis and technical effects

[0123] A, with the aid of an infrared thermal imager (FLIRA8400), the temperature of the sample is detected, and the result shows that the maximum temperature difference of the sample gauge section is 4.2℃, which is much better than the temperature gradient of ±30℃ of the traditional resistance furnace, fully illustrating the superiority of the test system in the aspect of temperature control.

[0124] B, through in-situ observation, the creep cavity of 0.08μm can be clearly observed. After shutdown, SEM (scanning electron microscope) is used for re-measurement, and the measurement value is 0.084μm, and the measurement error is less than 5%. While the resolution of the traditional metallographic detection is only 1μm, compared with the traditional metallographic detection, the damage resolution of the present application is significantly improved.

[0125] C, the single test of the present application only takes 6.5h, while the traditional multi-step test method needs 26h, the test efficiency is improved by 75%, the test period is greatly shortened, and the work efficiency is improved.

[0126] As can be seen from the above embodiments, the in-situ mechanical testing system and method of turbine blade material of aero-engine under high-temperature multi-axial composite load provided by the application can accurately simulate the actual working conditions of the turbine blade, realize real-time observation and quantitative analysis of the micro-damage evolution of the material, and provide strong technical support for performance evaluation and optimization design of the turbine blade material of the aero-engine.

[0127] In summary, the application has the following characteristics:

[0128] Integrated design: innovatively integrates high-frequency induction heating, multi-axis servo loading and in-situ microscopic observation into one, building a highly coordinated testing system. This integrated design not only improves testing efficiency, but also ensures accurate coordination between modules, providing a new solution for performance testing of high-temperature alloy materials under complex working conditions.

[0129] Multi-axis loading capability: through three-axis independent servo actuators, axial, radial and torsional composite loading is realized, breaking through the limitations of traditional single-axis testing. This multi-axis loading method can more realistically simulate the complex stress state of turbine blades in actual work, providing more accurate test conditions for material mechanical property evaluation.

[0130] High-frequency induction heating technology: high-frequency induction coils are used in combination with ZrO2 heat shields to locally and quickly heat the sample, with a heating temperature of 1100℃±5℃. Compared with traditional resistance high-temperature furnaces, high-frequency induction heating has the advantages of fast heating speed and good temperature uniformity, which can effectively eliminate the temperature field non-uniformity caused by traditional heating methods, ensuring the reliability of test data.

[0131] In-situ microscopic observation system: integrates long-working-distance high-temperature microscope lenses and high-speed cameras to record the micro-damage evolution of the material in the high-temperature loading process through a quartz observation window. This in-situ observation technology can realize high-resolution and high-frame-rate damage observation in a high-temperature environment, breaking through the limitations of traditional equipment in real-time capturing of material micro-damage during high-temperature loading, and providing an intuitive and accurate observation means for material failure analysis.

[0132] Temperature-stress decoupling control model: a temperature-stress decoupling control model is proposed, which monitors the induction heating power and the plastic deformation rate of the sample in real time, dynamically adjusts the induction heating power, compensates for the plastic deformation heat effect, and ensures accurate control of the sample temperature. This control model can effectively solve the problem of mutual interference between temperature and stress during high-temperature loading, improving the stability and accuracy of the testing process.

[0133] Damage quantification algorithm: a micro-defect identification model based on YOLOv5 is used to identify and quantify the micro-damage of the material in real time during the high-temperature loading process. This algorithm can accurately capture the critical point of creep crack initiation, providing important quantitative basis for material failure analysis and improving the scientificity and practicality of test results.

[0134] As shown in Figure 4 Another preferred embodiment of the present application also provides an in-situ mechanical testing device for turbine blade materials of an aero-engine, comprising:

[0135] A loading and heating synchronization module is used for loading and heating synchronization: the multi-axis loading unit and the high-temperature environment module are started, multi-axis composite loading and heating are carried out according to the pre-set loading parameters and heating program, the composite load of axial, radial and torsional is gradually applied, and the sample is heated to the target temperature. In the process of loading and heating, the stress and temperature changes of the sample are monitored in real time to ensure the synchronization and stability of loading and heating;

[0136] An in-situ observation and data acquisition module is used for in-situ observation and data acquisition: in the process of multi-axis composite loading and heating, the high-temperature microscope lens and high-speed camera of the in-situ observation system continuously shoot the images of the sample surface, capture the dynamic changes of micro-damage, and record the micro-damage evolution of the sample surface in real time, including the formation of creep cavities, the initiation and expansion of cracks. At the same time, the stress, temperature and damage image data of the sample are collected to provide detailed information for subsequent analysis;

[0137] A temperature-stress decoupling control module is used for temperature-stress decoupling control: the temperature-stress decoupling control model is used to monitor the inductive heating power and the plastic deformation rate of the sample in real time, and the inductive heating power is dynamically corrected according to the temperature-stress decoupling control model to compensate for the plastic deformation heat effect, so that the temperature of the sample is kept within the target temperature range, and the accurate control of the sample temperature is ensured;

[0138] A damage quantification analysis module is used for damage quantification analysis: through the micro-defect identification model, the collected damage image data are analyzed and quantified in real time, the micro-defects in the image are automatically identified, including cavities and cracks, and the area thereof is calculated; according to the damage factor formula, the damage factor D is calculated in real time to evaluate the damage degree of the sample in the high-temperature loading process; the change trend of the damage factor is used to judge the damage development process and critical point of the sample, and important basis is provided for material performance evaluation and failure analysis;

[0139] A data processing and analysis module is used for data processing and analysis: including stress-strain relationship analysis, temperature distribution and damage correlation analysis, damage evolution process analysis, performance evaluation and optimization suggestion;

[0140] Test result verification module for test result verification: including comparison with actual working conditions, comparison with existing standards and literature, and repetitive tests.

[0141] The application provides an aero-engine turbine blade material in-situ mechanical testing device, which adopts the aero-engine turbine blade material in-situ mechanical testing method in the above embodiment, and is used to solve the technical problems that the test results of the existing turbine blade material performance testing method deviate from the actual situation and failure mechanism information cannot be provided. Compared with the prior art, the aero-engine turbine blade material in-situ mechanical testing device provided by the application has the same beneficial effects as the aero-engine turbine blade material in-situ mechanical testing method provided by the above embodiment, and other technical features in the aero-engine turbine blade material in-situ mechanical testing device are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0142] As shown in the above embodiment, Figure 5 the preferred embodiment of the application further provides an electronic device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the steps of the aero-engine turbine blade material in-situ mechanical testing method in the above embodiment when executing the computer program.

[0143] The application provides an electronic device, which adopts the aero-engine turbine blade material in-situ mechanical testing method in the above embodiment, and is used to solve the technical problems that the test results of the existing turbine blade material performance testing method deviate from the actual situation and failure mechanism information cannot be provided. Compared with the prior art, the electronic device provided by the application has the same beneficial effects as the aero-engine turbine blade material in-situ mechanical testing method provided by the above embodiment, and other technical features in the electronic device are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0144] As shown in the above embodiment, Figure 6 the preferred embodiment of the application further provides a computer device, which can be a terminal or a living body detection server, and its internal structure diagram can be as shown in the above embodiment. Figure 6 The computer device includes a processor, a memory, and a network interface connected through a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operating system and the computer program in the non-volatile storage medium to run. The network interface of the computer device is used to communicate with other computer devices outside through a network connection. The computer program is executed by the processor to implement the steps of the above aero-engine turbine blade material in-situ mechanical testing method.

[0145] Those skilled in the art can understand that Figure 6 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0146] The computer device provided by the application adopts the in-situ mechanical testing method for turbine blade material of an aero-engine in the above-mentioned embodiment to solve the technical problem that the test result of the existing material performance testing method for a turbine blade deviates from the actual situation and cannot provide failure mechanism information. Compared with the prior art, the computer device provided by the application has the same beneficial effects as the in-situ mechanical testing method for turbine blade material of an aero-engine provided by the above-mentioned embodiment, and other technical features in the electronic device are the same as the features disclosed in the above-mentioned embodiment method, which will not be described here.

[0147] The preferred embodiment of the present application also provides a storage medium including a stored program, which controls the device where the storage medium is located to perform the steps of the in-situ mechanical testing method for turbine blade material of an aero-engine in the above-mentioned embodiment when the program is running.

[0148] Compared with the traditional scheme, the present application has the following significant technical effects:

[0149] Temperature uniformity: By high-frequency induction heating, the temperature uniformity of the sample is improved from ± 30℃ of the traditional resistance furnace to ± 5℃, effectively avoiding data distortion caused by local softening of the material.

[0150] Load dimension: Three-axis independent control is realized, which can accurately simulate the complex stress state of the turbine blade, while the traditional scheme can only realize single-axis loading.

[0151] Damage resolution: Through the in-situ dynamic observation system, the damage resolution is improved from ≥1pm of the traditional post-shutdown metallographic observation to 0.1pm, which can capture the critical point of creep crack initiation.

[0152] Test efficiency: Through multi-axis synchronous loading, the single test time is shortened from ≥24h of the traditional scheme to ≤8h, which significantly improves the test efficiency and shortens the research and development cycle by 60%.

[0153] It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described herein can be executed in an order different from that shown herein.

[0154] If the functions of the method in the embodiments are implemented in the form of software function units and sold or used as independent products, the software function units can be stored in one or more computer readable storage media. Based on such an understanding, the part of the prior art or the part of the technical solutions of the embodiments of the present application that make contributions to the prior art can be embodied in the form of a software product, which is stored in a storage medium and includes a number of instructions for causing a computer (which can be a personal computer, a server, a mobile computing device, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various media that can store program codes.

[0155] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROMs, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of the present application can be implemented in various computer languages, such as the object-oriented programming language C++ and the embedded programming language C.

[0156] The present application is described with reference to flowcharts and / or block diagrams according to the methods, devices (systems), and computer program products of the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device that implements the functions specified in the flowcharts and / or block diagrams. Figure One The functions specified in one or more flows and / or blocks. Figure One The functions specified in one or more flows and / or blocks.

[0157] These computer program instructions can also be stored in a computer readable storage medium that can direct the computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable storage medium produce a manufactured product including instruction devices that implement the functions specified in the flowcharts and / or block diagrams. Figure One The functions specified in one or more flows and / or blocks. Figure One The functions specified in one or more flows and / or blocks.

[0158] These computer program instructions can also be loaded into a computer or other programmable data processing devices, so that a series of operation steps are performed on the computer or other programmable devices to generate a computer implemented process, so that the instructions executed on the computer or other programmable devices provide a process for implementing the function specified in the flowchart Figure One one flow or multiple flows and / or the function specified in the block Figure One one block or multiple blocks.

[0159] The application also provides a computer program product comprising a computer program, which, when executed by a processor, implements the steps of the aero-engine turbine blade material in-situ mechanical testing method as described above.

[0160] The computer program product provided by the application can solve the technical problems of the existing aero-engine turbine blade material in-situ mechanical testing method scheme, such as complexity, difficulty in implementation, large amount of calculation, and high requirement for computing power. Compared with the prior art, the beneficial effects of the computer program product provided by the application are the same as those of the aero-engine turbine blade material in-situ mechanical testing method provided by the above-mentioned embodiments, and are not repeated here.

[0161] Although the preferred embodiments of the application have been described, those skilled in the art can make further changes and modifications to the embodiments once they know the basic inventive concept. Therefore, the appended claims are intended to be interpreted as including all changes and modifications falling within the scope of the application.

[0162] Obviously, those skilled in the art can make various modifications and variations to the application without departing from the spirit and scope of the application. Thus, if these modifications and variations of the application fall within the scope of the claims of the application and their equivalent technologies, the application also intends to include these modifications and variations.

Claims

1. An in-situ mechanical testing system for aero-engine turbine blade materials, characterized in that, include: Multi-axis loading unit: Employs three independent servo actuators to achieve axial, radial, and torsional loading respectively, simulating the multi-axis stress state of turbine blades under actual working conditions; High-temperature environment module: Used to achieve localized rapid heating of the sample by using a high-frequency induction coil in conjunction with a heat shield for temperature loading of turbine blade samples; In-situ observation system: integrates a high-temperature microscope lens with a long working distance and a high-speed camera, used to observe and record the micro-damage evolution of turbine blade samples in real time during high-temperature loading through a quartz observation window; The control unit has a built-in temperature-stress decoupling control model and a micro-defect identification model, which are used to compensate for the thermal effects of plastic deformation in real time and quantify the damage factor D, where the damage factor D = ∑ void area / observation area.

2. The in-situ mechanical testing system for aero-engine turbine blade materials according to claim 1, characterized in that, The multi-axis loading unit has an axial load of ±50kN, a radial load of ±30kN, a torsional load of ±200Nm, a frequency range of 0-100Hz, and an accuracy of ±0.1%FS.

3. The in-situ mechanical testing system for aero-engine turbine blade materials according to claim 1, characterized in that, The high-frequency induction coil of the high-temperature environment module has a frequency of over 200kHz, and the heat insulation cover material is ZrO2, with a heating temperature of 1100℃±5℃.

4. The in-situ mechanical testing system for aero-engine turbine blade materials according to claim 1, characterized in that, The magnification of the long working distance high-temperature microscope lens is above 1000x, and the frame rate of the high-speed camera is above 5000fps.

5. A method for in-situ mechanical testing of aero-engine turbine blade materials, based on the in-situ mechanical testing system for aero-engine turbine blade materials as described in any one of claims 1 to 4, characterized in that, Including the following steps: S1. Synchronous loading and heating: The multi-axis loading unit and high-temperature environment module are activated. Multi-axis composite loads are applied and heated according to the pre-set loading parameters and heating program. Axial, radial and torsional composite loads are applied gradually, and the sample is heated to the target temperature at the same time. During the loading and heating process, the stress and temperature changes of the sample are monitored in real time to ensure the synchronicity and stability of loading and heating. S2. In-situ observation and data acquisition: During multiaxial composite loading and heating, images of the sample surface are continuously captured by the high-temperature microscope and high-speed camera of the in-situ observation system to capture the dynamic changes of micro-damage and record the evolution of micro-damage on the sample surface in real time, including the formation of creep cavities, crack initiation and propagation. At the same time, stress, temperature and damage image data of the sample are acquired to provide detailed information for subsequent analysis. S3. Temperature-Stress Decoupling Control: Using a temperature-stress decoupling control model, the induction heating power and the plastic deformation rate of the sample are monitored in real time. The induction heating power is dynamically corrected according to the temperature-stress decoupling control model to compensate for the thermal effect of plastic deformation, so that the sample temperature is kept within the target temperature range and the sample temperature is accurately controlled. S4. Damage Quantification Analysis: Through the micro-defect identification model, the collected damage image data is analyzed and quantified in real time, automatically identifying micro-defects in the image, including voids and cracks, and calculating their area. Based on the damage factor formula, the damage factor D is calculated in real time to assess the degree of damage to the sample during high-temperature loading. The trend of the damage factor is used to determine the damage development process and critical point of the sample, providing an important basis for material performance evaluation and failure analysis. S5. Data Processing and Analysis: This includes stress-strain relationship analysis, temperature distribution and damage correlation analysis, damage evolution process analysis, performance evaluation, and optimization suggestions. S6. Verification of test results: including comparison with actual working conditions, comparison with existing standards and literature, and repeatability testing.

6. The in-situ mechanical testing method for aero-engine turbine blade materials according to claim 5, characterized in that, In step S1, the high-temperature PST titanium-aluminum single crystal used for aero-engine turbine blades is selected as the test material. After the shape and size of the sample are processed according to the requirements, the surface of the sample needs to be finely processed to reduce the influence of surface defects on the test results. The target temperature is 1100℃±5℃.

7. The in-situ mechanical testing method for aero-engine turbine blade materials according to claim 5, characterized in that, In step S3: The temperature-stress decoupling control model is as follows: Among them, T actual For the actual temperature, P induction For induction heating power, K is the plastic deformation rate, and k1 and k2 are compensation coefficients.

8. The in-situ mechanical testing method for aero-engine turbine blade materials according to claim 5, characterized in that, In step S4: By using the YOLOv5 micro-defect recognition model, the acquired damage image data is analyzed and quantified in real time, automatically identifying micro-defects in the images, including voids and cracks, and calculating their areas. The formula for calculating the damage factor D is: D = ∑ void area / observation area.

9. The in-situ mechanical testing method for aero-engine turbine blade materials according to claim 5, characterized in that, In step S5: The stress-strain relationship analysis specifically includes: processing the collected stress and strain data, plotting stress-strain curves, analyzing the mechanical behavior of the specimen under multiaxial combined loads, evaluating the strength and toughness of the specimen through the characteristic points of the curves, including the yield point and the fracture point, comparing the stress-strain relationship under different loading paths, and studying the influence of multiaxial stress state on the mechanical properties of the specimen. The temperature distribution and damage correlation analysis specifically includes: combining temperature data and damage images to analyze the relationship between temperature distribution and micro-damage of the sample under high temperature environment, studying the influence of temperature gradient on micro-damage evolution, determining the damage difference between high temperature region and low temperature region, and revealing the influence mechanism of temperature field inhomogeneity on material properties through temperature-damage correlation analysis. Damage evolution process analysis specifically includes: analyzing the damage image sequence acquired by the in-situ observation system, reconstructing the micro-damage evolution process of the sample during high-temperature loading, determining the initiation, development and expansion laws of micro-damage through image comparison and the changing trend of damage factors, and analyzing the formation mechanism of different damage modes, such as the relationship between the formation of creep cavities and the initiation and expansion of cracks. The performance evaluation and optimization recommendations specifically include: comprehensively evaluating the performance of high-temperature alloys under actual service conditions by integrating mechanical property data, temperature distribution data, and micro-damage evolution information; and proposing material performance optimization recommendations based on test results, including improving alloy composition, adjusting processing technology, or optimizing loading conditions, to provide a scientific basis for the design and manufacturing of aero-engine turbine blades and improve their reliability and service life.

10. The in-situ mechanical testing method for aero-engine turbine blade materials according to claim 5, characterized in that, In step S6: The comparison with actual working conditions specifically includes: comparing and verifying the test results with the stress state, temperature distribution and damage mode of aero-engine turbine blades in actual service. Through comparative analysis, the effectiveness and reliability of the test method are verified, and the test results are ensured to accurately reflect the performance of the material under actual working conditions. The comparison with existing standards and literature specifically includes: comparing the test results with existing material performance standards and related literature to verify the accuracy and consistency of the test methods; and through comparative analysis, ensuring that the test results meet industry standards and academic consensus, thus providing a reliable reference for material performance evaluation. Repeatability testing specifically includes: performing repeated tests on the same material multiple times to verify the repeatability and stability of the test method; evaluating the dispersion and reliability of the test results through statistical analysis to ensure that the test method can stably provide consistent test results and provide reliable experimental data support for material performance research.

Images