Aero-engine turbine blade material in-situ mechanical testing system and method

Abstract

This application discloses an in-situ mechanical testing system and method for aero-engine turbine blade materials. The system includes: a multi-axis loading unit for simulating the multi-axis stress state of turbine blades under actual operating conditions; a high-temperature environment module for achieving localized rapid heating of the sample; an in-situ observation system integrating a long-working-distance high-temperature microscope and a high-speed camera for real-time observation and recording of the microscopic damage evolution of the turbine blade sample during high-temperature loading; and a control unit with a built-in temperature-stress decoupling control model and a microscopic defect identification model for real-time compensation of the thermal effects of plastic deformation and quantification of the damage factor D. This application achieves synchronous loading of centrifugal force through a three-axis servo actuator, accurately reproducing composite stress with small load errors, overcoming the limitation of traditional single-axis testing in simulating multi-source loads on blades. Simultaneously, this application reduces interference from plastic work-induced temperature rise, solving the technical problem of data distortion caused by temperature drift in high-temperature testing.

Description

Technical Field

[0001] This application relates to the field of aerospace alloy material performance testing technology, and in particular, to an in-situ mechanical testing system and method for aero-engine turbine blade materials. Background Technology

[0002] As a core component of an aircraft, the performance of the aero-engine directly affects the aircraft's flight performance and safety. Turbine blades, as one of the key hot-end components of an aero-engine, operate under extreme conditions such as high temperature, high pressure, and high speed, and must withstand multi-source loads including centrifugal force, aerodynamic force, and thermal cycling. Therefore, the material properties of turbine blades are crucial to the engine's performance and reliability.

[0003] Traditional mechanical testing methods, such as uniaxial tensile or compression tests, while providing basic mechanical property data of materials, have the following limitations:

[0004] Uniaxial testing dominates: Universal testing machines can only simulate single tensile or compressive loads and cannot reproduce the multiaxial stress state experienced by turbine blades in actual operation. This single-load testing method cannot comprehensively evaluate the material's performance under actual working conditions and may lead to misjudgments of material properties.

[0005] High-temperature environment distortion: Existing high-temperature testing equipment, such as resistance furnaces, exhibits large temperature gradients during heating, making it impossible to guarantee temperature uniformity of the sample under high-temperature conditions. Furthermore, these devices cannot simultaneously apply complex loads, such as centrifugal force and aerodynamic forces, leading to deviations between test results and actual operating conditions, thus affecting the accuracy of the test results.

[0006] Lack of damage observation: Existing testing equipment struggles to capture the real-time evolution of microscopic damage in materials during high-temperature loading, such as creep voids and crack initiation. The evolution of these microscopic damages is crucial for understanding material failure mechanisms, but traditional testing methods often fail to provide this information.

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

[0008] This application provides an in-situ mechanical testing method for aero-engine turbine blade materials, which addresses the issues of discrepancies between existing turbine blade material performance testing methods and actual results, as well as the inability to provide information technology for failure mechanisms.

[0009] This application is achieved through the following solution:

[0010] An in-situ mechanical testing system for aero-engine turbine blade materials includes:

[0011] 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;

[0012] 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;

[0013] 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;

[0014] The control unit incorporates a temperature-stress decoupling control model and a micro-defect identification model to compensate for the thermal effects of plastic deformation in real time and quantify the damage factor D.

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

[0016] Furthermore, the high-frequency induction coil of the high-temperature environment module has a frequency of over 200kHz, the heat insulation cover material is ZrO2, and the heating temperature reaches 1100℃±5℃.

[0017] Furthermore, 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.

[0018] This application also provides an in-situ mechanical testing method for aero-engine turbine blade materials, based on the aforementioned in-situ mechanical testing system for aero-engine turbine blade materials, comprising the following steps:

[0019] 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.

[0020] 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.

[0021] 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.

[0022] S4. Damage Quantification Analysis: Through a micro-defect identification 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; 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 damage factor changes 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.

[0023] 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.

[0024] S6. Verification of test results: including comparison with actual working conditions, comparison with existing standards and literature, and repeatability testing.

[0025] Furthermore, 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.

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

[0027] Furthermore, in step S3:

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

[0029]

[0030] 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.

[0031] Furthermore, in step S4:

[0032] 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.

[0033] The formula for calculating the damage factor D is: D = ∑ void area / observation area.

[0034] Furthermore, in step S5:

[0035] 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.

[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, 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.

[0037] 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.

[0038] 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.

[0039] Furthermore, 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 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.

[0041] 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.

[0042] 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.

[0043] Compared with the prior art, this application has the following advantages:

[0044] This application provides an in-situ mechanical testing system and method for aero-engine turbine blade materials. This application utilizes a three-axis servo actuator to simultaneously apply centrifugal force (axial), aerodynamic force (radial), and torque (torsional), accurately reproducing composite stress with a load error of <±0.1%FS, overcoming the limitation of traditional single-axis testing in simulating multi-source loads on blades. Simultaneously, this application employs thermo-mechanical dynamic decoupling control, real-time correcting the heating power through the plastic deformation rate, reducing temperature rise interference caused by plastic work (temperature drift controlled within ±3℃), and solving the technical problem of data distortion caused by temperature drift in high-temperature testing.

[0045] In addition to the purposes, features, and advantages described above, this application has other purposes, features, and advantages. A further detailed description of this application will be provided below with reference to the figures. Attached Figure Description

[0046] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0047] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0048] Figure 1 This is a schematic diagram of the composition of an in-situ mechanical testing system for aero-engine turbine blade materials according to a preferred embodiment of this application;

[0049] Figure 2 This is a schematic diagram of the YOLOv5 model recognition flowchart of a preferred embodiment of this application;

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

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

[0052] Figure 5 This is a schematic block diagram of an electronic device according to a preferred embodiment of this application;

[0053] Figure 6 This is an internal structural diagram of a computer device according to a preferred embodiment of this application. Detailed Implementation

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

[0055] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0056] In the following examples, high-temperature PST titanium-aluminum single crystals for aero-engine turbine blades were selected as the test material to ensure that they are representative and typical.

[0057] Sample preparation

[0058] Titanium-aluminum single crystals were machined into dumbbell-shaped specimens using wire cutting technology, with gauge length dimensions of 15 mm (length) × 3 mm (width) × 1.5 mm (thickness). M6 threaded interfaces were machined at both ends of the specimens for clamping with multi-axis fixtures. The specimens were treated in a mixed electrolyte (perchloric acid:ethanol = 1:9) at 20 V for 30 s to remove the work-hardened layer. Fluorescent markers, consisting of 0.1 μm diameter ZrO2 particles, were sprayed onto the observation area of ​​the specimens for in-situ image displacement tracking under high-temperature conditions, serving as reference points for this tracking.

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

[0060] like Figure 1 As shown, a preferred embodiment of this application provides an in-situ mechanical testing system for aero-engine turbine blade materials, comprising:

[0061] Multi-axis loading unit: Employs three independent servo actuators to achieve axial, radial, and torsional loading respectively, simulating the combined stress state of centrifugal force and aerodynamic load on the blade during actual operation. For example, the axial load of the multi-axis loading unit is +40kN (tensile) / -35kN (compression), radial load is ±25kN, torque is ±180Nm, and frequency is 80Hz (simulating engine speed of 12,000rpm).

[0062] The load accuracy was calibrated using a laser displacement sensor (±0.08% FS);

[0063] 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;

[0064] 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;

[0065] The control unit incorporates a temperature-stress decoupling control model and a micro-defect identification model to compensate for the thermal effects of plastic deformation in real time and quantify the damage factor D.

[0066] Compared with traditional solutions, this embodiment has the following significant technical advantages:

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

[0068] Load dimension: It achieves independent control of three axes, which can accurately simulate the complex stress state of turbine blades, while traditional solutions can only achieve single-axis loading.

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

[0070] Testing efficiency: By using multi-axis synchronous loading, the time for a single test is reduced from ≥24h in the traditional approach to ≤8h, which significantly improves testing efficiency and shortens the R&D cycle by 60%.

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

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

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

[0074] Reference Figure 2 The control unit incorporates a temperature-stress decoupling control model and a micro-defect identification model based on YOLOv5, which are used to compensate for the thermal effects of plastic deformation in real time and quantify the damage factor D, where damage factor D = ∑ void area / observation area.

[0075] like Figure 3 As shown, another preferred embodiment of this application also provides an in-situ mechanical testing method for aero-engine turbine blade materials, based on the aforementioned in-situ mechanical testing system for aero-engine turbine blade materials, including the following steps:

[0076] 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.

[0077] 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.

[0078] 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.

[0079] S4. Damage Quantification Analysis: Through a micro-defect identification 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; 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 damage factor changes 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.

[0080] 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.

[0081] S6. Verification of test results: including comparison with actual working conditions, comparison with existing standards and literature, and repeatability testing.

[0082] This embodiment provides an in-situ mechanical testing method for aero-engine turbine blade materials. Through the above testing method, it is possible to comprehensively and accurately simulate the multiaxial composite load and high-temperature environment of nickel-based superalloys used in aero-engine turbine blades during actual service, observe the micro-damage evolution of materials in real time, provide a scientific basis for material performance evaluation and failure analysis, and provide important technical support for the design and manufacturing of aero-engine turbine blades.

[0083] Preferably, 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.

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

[0085] Preferably, in step S3:

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

[0087]

[0088] 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.

[0089] Preferably, in step S4:

[0090] 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.

[0091] The formula for calculating the damage factor D is: D = ∑ void area / observation area.

[0092] Preferably, in step S5:

[0093] 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.

[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 properties through temperature-damage correlation analysis.

[0095] 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.

[0096] 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.

[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 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.

[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 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.

[0100] 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.

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

[0102] The testing process is as follows:

[0103] Synchronous loading and heating:

[0104] Based on the high-temperature environment module, the sample was heated at a rate of 200℃ / s until it reached 1100℃. The temperature was fed back in real time by a dual-color infrared thermometer, and the PID algorithm controlled the fluctuation within ±3℃. At the same time, a composite load was applied to the sample, specifically +40kN axially, +25kN radially, and +180Nm torque, to simulate the stress state under aircraft takeoff conditions.

[0105] In-situ observation and data acquisition:

[0106] 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 collected to provide detailed information for subsequent analysis.

[0107] Temperature-stress decoupling control:

[0108] When the plastic deformation rate ε is monitored plastic >5×10 -5 s -1 At that time, 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), automatically reducing the induction power by 5%, thereby suppressing the sample temperature rise and maintaining temperature stability.

[0109] In-situ damage quantification:

[0110] YOLOv5 model recognition process: A high-speed camera acquires images of the observation area of ​​the sample, with each frame taking 0.2ms; the YOLOv5 model is used to segment and identify cavities and cracks in the images, with a confidence level of >95% (trained using 500 sets of SEM-annotated images, with a test set recognition accuracy of 98.7% and a cavity area measurement error of <5%); the area S_i of a single cavity is calculated.

[0111] The formula for calculating the damage factor D is D = ∑S_i / 4mm 2 (The area of ​​the observation area is 2mm×2mm.)

[0112] The critical point warning value is set to D≥0.03. When the damage factor exceeds the critical point, an early warning is triggered.

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

[0114] Table 1 - Typical Damage Evolution Data

[0115] Time (min) 0 30 120 180 (critical point) Damage Factor D 0 0.008 0.019 0.032 Damage type - Microcavity Void aggregation Crack initiation

[0116] Result verification:

[0117] 1. Comparison with actual working conditions

[0118] Tests revealed that the location of crack initiation during blade service was consistent with the observation area in this experiment, both located in the stress concentration zone in the middle of the blade.

[0119] 2. Repeatability verification

[0120] Table 2 - Results of Repeatability Verification Tests

[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 Technological Effects

[0123] A. The temperature of the sample was detected using an infrared thermal imager (FLIRA8400). The results showed that the maximum temperature difference in the gauge length of the sample was 4.2℃. This result is far superior to the ±30℃ temperature gradient of the traditional resistance furnace, which fully demonstrates the superiority of this testing system in terms of temperature control.

[0124] B. Through in-situ observation, creep cavities as small as 0.08 μm can be clearly observed. After shutdown, a re-measurement was performed using SEM (scanning electron microscope), and the measured value was 0.084 μm, with a measurement error of less than 5%. In contrast, the resolution of traditional metallographic testing is only 1 μm, indicating a significant improvement in damage resolution in this application.

[0125] C. This application's single test only takes 6.5 hours, while the traditional multi-step testing method takes 26 hours, improving testing efficiency by 75%, greatly shortening the testing cycle, and improving work efficiency.

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

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

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

[0129] Multi-axis loading capability: By using three independent servo actuators, composite loading of axial, radial, and torsional forces is achieved, breaking through the limitations of traditional single-axis testing. This multi-axis loading method can more realistically simulate the complex stress state that turbine blades experience in actual operation, providing more accurate test conditions for evaluating the mechanical properties of materials.

[0130] High-frequency induction heating technology: This technology uses a high-frequency induction coil in conjunction with a ZrO2 heat shield to rapidly heat the sample locally, reaching temperatures of up to 1100℃±5℃. Compared to traditional resistance high-temperature furnaces, high-frequency induction heating offers advantages such as faster heating speed and better temperature uniformity, effectively eliminating the temperature field inhomogeneity caused by traditional heating methods and ensuring the reliability of test data.

[0131] In-situ microscopic observation system: This system integrates a long-working-distance high-temperature microscope lens and a high-speed camera, recording the microscopic damage evolution of materials in real time during high-temperature loading through a quartz observation window. This in-situ observation technology enables high-resolution, high-frame-rate damage observation in high-temperature environments, overcoming the limitations of traditional equipment in capturing microscopic damage in materials in real time during high-temperature loading, and providing an intuitive and accurate observation method for material failure analysis.

[0132] Temperature-Stress Decoupling Control Model: A temperature-stress decoupling control model is proposed. By monitoring the induction heating power and the plastic deformation rate of the specimen in real time, the induction heating power is dynamically adjusted to compensate for the thermal effects of plastic deformation, ensuring precise temperature control of the specimen. 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: Based on the YOLOv5 micro-defect identification model, this algorithm performs real-time identification and quantification of micro-damage in materials during high-temperature loading. It accurately captures the critical point for creep crack initiation, providing crucial quantitative evidence for material failure analysis and enhancing the scientific rigor and practicality of test results.

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

[0135] The loading and heating synchronization module is used to synchronize loading and heating: it starts the multi-axis loading unit and high-temperature environment module, and performs multi-axis composite load loading and heating according to the preset loading parameters and heating program. It gradually applies axial, radial and torsional composite loads, and heats the sample to the target temperature at the same time. During the loading and heating process, it monitors the stress and temperature changes of the sample in real time to ensure the synchronization and stability of loading and heating.

[0136] The in-situ observation and data acquisition module is used for in-situ observation and data acquisition: During multi-axis composite load loading and heating, the high-temperature microscope and high-speed camera of the in-situ observation system continuously capture images of the sample surface, 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, it acquires stress, temperature and damage image data of the sample to provide detailed information for subsequent analysis.

[0137] The temperature-stress decoupling control module is used for temperature-stress decoupling control: it uses the temperature-stress decoupling control model to monitor the induction heating power and the plastic deformation rate of the sample in real time, and dynamically corrects the induction heating power according to the temperature-stress decoupling control model to compensate for the heat effect of plastic deformation, so that the sample temperature is kept within the target temperature range and the sample temperature is accurately controlled.

[0138] The damage quantification analysis module is used for damage quantification analysis: through a micro-defect identification model, it performs real-time analysis and quantification of the acquired damage image data, automatically identifies micro-defects in the images, including voids and cracks, and calculates their area; according to the damage factor formula, it calculates the damage factor D in real time to evaluate the degree of damage to the sample during high-temperature loading; the trend of damage factor change 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.

[0139] The 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 suggestions;

[0140] The test result verification module is used to verify test results, including comparison with actual working conditions, comparison with existing standards and literature, and repeatability testing.

[0141] This application provides an in-situ mechanical testing device for aero-engine turbine blade materials, employing the in-situ mechanical testing method for aero-engine turbine blade materials described in the above embodiments. This addresses the problems of discrepancies between test results and actual conditions, and the inability to provide information technology regarding failure mechanisms, in existing turbine blade material performance testing methods. Compared to the prior art, the beneficial effects of the in-situ mechanical testing device for aero-engine turbine blade materials provided in this application are the same as those of the in-situ mechanical testing method for aero-engine turbine blade materials provided in the above embodiments. Furthermore, other technical features of the in-situ mechanical testing device for aero-engine turbine blade materials are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0142] like Figure 5 As shown, a preferred embodiment of this application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the in-situ mechanical testing method for aero-engine turbine blade materials described in the above embodiments.

[0143] The application provides an electronic device that employs the in-situ mechanical testing method for aero-engine turbine blade materials described in the above embodiments. This method addresses the problems of discrepancies between existing turbine blade material performance testing methods and actual results, as well as the inability to provide information technology for failure mechanisms. Compared to the prior art, the electronic device provided in this application has the same beneficial effects as the in-situ mechanical testing method for aero-engine turbine blade materials provided in the above embodiments, and other technical features of the electronic device are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0144] like Figure 6 As shown, a preferred embodiment of this application also provides a computer device, which may be a terminal or a liveness detection server, and its internal structure diagram may be as follows. Figure 6 As shown, the computer device includes a processor, memory, and a network interface connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The network interface is used to communicate with other external computer devices via a network connection. When the computer program is executed by the processor, it implements the steps of the aforementioned in-situ mechanical testing method for aero-engine turbine blade materials.

[0145] Those skilled in the art will understand that Figure 6 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0146] The computer equipment provided in this application employs the in-situ mechanical testing method for aero-engine turbine blade materials described in the above embodiments. This method addresses the problems of discrepancies between test results and actual conditions, and the inability to provide information technology information on failure mechanisms, inherent in existing turbine blade material performance testing methods. Compared to the prior art, the beneficial effects of the computer equipment provided in this application are the same as those of the in-situ mechanical testing method for aero-engine turbine blade materials provided in the above embodiments. Furthermore, other technical features of the electronic equipment are identical to those disclosed in the methods of the above embodiments, and will not be elaborated upon here.

[0147] A preferred embodiment of this application also provides a storage medium, the storage medium including a stored program, which, when the program is executed, controls the device where the storage medium is located to perform the steps of the in-situ mechanical testing method for aero-engine turbine blade materials in the above embodiments.

[0148] Compared with traditional solutions, the present invention has the following significant technical advantages:

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

[0150] Load dimension: It achieves independent control of three axes, which can accurately simulate the complex stress state of turbine blades, while traditional solutions can only achieve single-axis loading.

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

[0152] Testing efficiency: By using multi-axis synchronous loading, the time for a single test is reduced from ≥24h in the traditional approach to ≤8h, which significantly improves testing efficiency and shortens the R&D cycle by 60%.

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

[0154] If the functions described in this embodiment are implemented as software functional units and sold or used as independent products, they can be stored in one or more computing device-readable storage media. Based on this understanding, the parts of this application's embodiments that contribute to the prior art or the technical solutions can be embodied in the form of a software product. This software product is stored in a storage medium and includes several instructions to cause a computing device (which may be a personal computer, server, mobile computing device, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage media include: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media capable of storing program code.

[0155] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this 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-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of this application can be implemented using various computer languages, such as the object-oriented programming language C++ and the embedded programming language C.

[0156] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations 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, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0157] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0158] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0159] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the in-situ mechanical testing method for aero-engine turbine blade materials as described above.

[0160] The computer program product provided in this application can solve the technical problems of existing in-situ mechanical testing methods for aero-engine turbine blade materials being complex, difficult to implement, computationally intensive, and requiring high computing power. Compared with the prior art, the beneficial effects of the computer program product provided in this application are the same as those of the in-situ mechanical testing method for aero-engine turbine blade materials provided in the above embodiments, and will not be repeated here.

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

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

Claims

1. A method for in-situ mechanical testing of aero-engine turbine blade materials, 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: A temperature-stress decoupling control model is used to monitor the induction heating power and the plastic deformation rate of the sample in real time. The induction heating power is dynamically adjusted based on the model to compensate for the thermal effects of plastic deformation, ensuring the sample temperature remains within the target range and guaranteeing precise temperature control. The temperature-stress decoupling control model is as follows: ； in, T actual This is the actual temperature. P induction For induction heating power, For plastic deformation rate, k 1 and k 2 is the compensation coefficient; S4. Damage Quantification Analysis: Through a micro-defect identification 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; 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 damage factor changes 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.

2. The aeroengine turbine blade material in-situ mechanical testing method of claim 1, wherein, 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℃.

3. The aeroengine turbine blade material in-situ mechanical testing method of claim 1, wherein, 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 = ∑ cavity area / observation area.

4. The in-situ mechanical testing method for aero-engine turbine blade materials according to claim 1, 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.

5. The in-situ mechanical testing method for aero-engine turbine blade materials according to claim 1, 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.

6. An in-situ mechanical testing system for aero-engine turbine blade materials, used to implement the method as described in any one of claims 1 to 5, 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.

7. The aeroengine turbine blade material in-situ mechanical testing system of claim 6, wherein, 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.

8. The in-situ mechanical testing system for aero-engine turbine blade materials according to claim 6, 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℃.

9. The aeroengine turbine blade material in-situ mechanical testing system of claim 6, wherein, 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.

Images