Dynamic Young modulus measuring method and device based on frequency sweeping mode

Abstract

The invention belongs to the technical field of material mechanical property testing, and discloses a dynamic Young modulus measuring method and device based on a frequency sweeping mode. The method comprises the following steps: carrying out sweep frequency excitation on a standard test rod through a non-contact vibration exciter to enable the standard test rod to generate bending vibration; synchronously acquiring vibration response data in a non-contact manner by adopting a laser vibration meter, and performing spectrum analysis through a signal acquisition and processing system to obtain an amplitude response spectrum; identifying at least one harmonic peak of bending vibration from the frequency spectrum, and accurately acquiring a corresponding resonant frequency; and dynamically calculating the Young modulus of the material according to the measured resonant frequency in combination with the geometric and physical parameters of the test rod and the corresponding vibration mode. According to the invention, non-contact excitation and measurement, a sweep frequency mode and an accurate spectrum analysis technology are combined, additional mass and rigidity errors introduced by contact measurement can be avoided, and the method has the advantages of high measurement precision, high speed, good repeatability, huge automation potential and the like.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of material mechanical property testing, and in particular to a dynamic Young's modulus measurement method and device based on a sweep frequency mode. Background Art

[0002] Young's modulus is a key physical quantity that characterizes a material's elastic properties. It reflects the strength of the interatomic bonds within the material and is a crucial indicator for material application and quality control. Existing methods for measuring Young's modulus primarily include static tensile testing, ultrasonic testing, and dynamic resonance testing.

[0003] Static tensile testing methods have the disadvantage of damaging the specimen, making them unsuitable for online and batch testing. Ultrasonic testing methods have strict requirements for the test environment and operating conditions, resulting in limited measurement error. Existing dynamic measurement methods, primarily based on resonance, still face several technical bottlenecks. For example, the widely used impact excitation method, which induces sample vibration through mechanical impact, makes it difficult to precisely control the excitation energy and position, resulting in poor measurement repeatability. Furthermore, it is often used in conjunction with acoustic sensors such as microphones, making it susceptible to interference from ambient noise and limiting accuracy. To overcome this issue, some technologies use contact-type actuators (such as piezoelectric or electromagnetic transducers) to directly drive the sample. However, this inevitably introduces additional mass and stiffness, altering the sample's inherent vibration characteristics and causing systematic errors in the measurement results. This makes it particularly unsuitable for precise measurement of thin or small samples. Although some high-end solutions have incorporated non-contact technologies such as laser vibrometers at the measurement end, improving the accuracy of response acquisition, their combination of non-contact excitation sources, precise control, and efficient frequency sweeping modes remains imperfect, making it difficult to meet the demands of modern industrial production for rapid, automated, and high-precision online monitoring of material properties. Summary of the Invention

[0004] In order to overcome the problems existing in the prior art, the present invention provides a dynamic Young's modulus measurement method and device based on a sweep frequency mode, which can realize fast, accurate and non-contact measurement of the Young's modulus of materials and meet the needs of industrial production for material performance monitoring.

[0005] In a first aspect, the present invention provides a dynamic Young's modulus measurement method based on a frequency sweep mode, comprising:

[0006] Step 1: Make the material to be tested into a standard test rod and install it on the measurement support device;

[0007] Step 2: Generate a sweep frequency excitation signal within a specific frequency range through a signal source, amplify the sweep frequency excitation signal through a power amplifier, and then input it into a non-contact vibrator, which performs sweep frequency excitation on the test rod;

[0008] Step 3: measuring the vibration response data of the test rod under the sweep frequency excitation by a laser vibrometer, and sending the vibration response data to a signal acquisition and processing system;

[0009] Step 4: Performing spectrum analysis on the vibration response data through a signal acquisition and processing system to obtain an amplitude response spectrum;

[0010] Step 5: identifying at least one resonant frequency corresponding to a bending vibration resonance peak from the amplitude response spectrum;

[0011] Step 6: Calculate the Young's modulus of the material based on the resonant frequency, the geometry and physical parameters of the test rod, and the corresponding vibration mode.

[0012] Optionally, the specific frequency range is any sub-range of 1 Hz-10 kHz.

[0013] Optionally, the non-contact exciter applies an excitation force to the test rod in a non-contact manner through acoustic wave coupling, so that the test rod generates bending vibration.

[0014] Optionally, the resonant frequency is a first-order bending vibration frequency.

[0015] Optionally, step 5 specifically includes:

[0016] The frequency corresponding to the amplitude maximum point in the amplitude response spectrum is used as the resonant frequency; or,

[0017] Curve fitting is performed on spectrum data near the amplitude maximum point in the amplitude response spectrum, and the resonant frequency is estimated based on the fitting curve.

[0018] Optionally, for a circular cross-section rod with a simply supported beam boundary condition, the Young's modulus in step 6 is calculated as follows:

[0019]

[0020] Where m is the material mass, L is the length of the test rod, and f n is the measured first-order bending vibration frequency, that is, the resonant frequency measured in step 5, and d is the diameter of the test rod.

[0021] Optionally, for a rectangular cross-section rod with a simply supported beam boundary condition, the Young's modulus in step 6 is calculated as:

[0022]

[0023] Where m is the material mass, L is the length of the test rod, and f n is the measured first-order bending vibration frequency, h is the thickness of the test rod, and b is the width of the test rod.

[0024] Optionally, for a circular cross-section rod with a cantilever beam boundary condition, the calculation formula for the Young's modulus in step 6 is:

[0025]

[0026] Where ρ is the material density, L is the length of the test rod, and f n is the measured first-order bending vibration frequency, and d is the diameter of the test rod.

[0027] Optionally, for a rectangular cross-section rod with a cantilever beam boundary condition, the Young's modulus in step 6 is calculated as follows:

[0028]

[0029] Where ρ is the material density, L is the length of the test rod, and f n is the measured first-order bending vibration frequency, and h is the thickness of the rectangular test rod.

[0030] Optionally, after step 6, the method further includes:

[0031] It is determined whether the obtained Young's modulus value is within the preset standard range, and the measurement result and the judgment result are presented on the display.

[0032] In a second aspect, an embodiment of the present invention further provides a dynamic Young's modulus measurement device based on a sweep frequency mode, comprising:

[0033] A measurement support device, a signal source, a power amplifier, a non-contact vibrator, a laser vibrometer, and a signal acquisition and processing system; the signal source is connected to the power amplifier and the laser vibrometer respectively; the power amplifier is connected to the non-contact vibrator, and the laser vibrometer is connected to the signal acquisition and processing system;

[0034] The signal source is used to generate a sweep frequency excitation signal within a specific frequency range and send it to the power amplifier, and synchronously provide a trigger signal to the non-contact exciter;

[0035] The power amplifier is used to amplify the sweep frequency excitation signal and then send it to the non-contact exciter;

[0036] The non-contact exciter is used to apply sweep frequency excitation to the test rod;

[0037] The laser vibrometer is used to measure the vibration response data of the test rod under the sweep frequency excitation and send the vibration response data to the signal acquisition and processing system;

[0038] The signal acquisition and processing system is used to perform spectrum analysis and Young's modulus value calculation on the collected vibration response data.

[0039] Optionally, the laser wavelength used by the laser vibrometer is a visible light band, a near infrared band or a combination thereof, which is suitable for non-contact vibration measurement of the test rod. The laser wavelength range can be selected from the band of 500nm to 600nm.

[0040] Optionally, the measurement support device adopts a simply supported beam support method or a cantilever beam support method.

[0041] Optionally, the device further includes: a display connected to the signal acquisition and processing system, for displaying the measurement results and judgment results of the test rod.

[0042] This invention utilizes non-contact excitation and laser vibration measurement technology, combined with swept-frequency excitation and spectrum fitting analysis, to achieve rapid and accurate measurement of a material's dynamic Young's modulus. The measurement process is highly automated, making it suitable for industrial online testing applications. Furthermore, the measurement device employs a simply supported beam structure or cantilever beam support to simplify the device design and reduce operational complexity. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A schematic diagram of a dynamic Young's modulus measurement device based on a frequency sweep mode provided by the present invention;

[0044] Figure 2 A structural diagram of a dynamic Young's modulus measurement device based on a frequency sweep mode provided by the present invention;

[0045] Figure 3 A structural diagram of a measurement support device provided by the present invention;

[0046] Figure 4 A flow chart of a dynamic Young's modulus measurement method based on a sweep frequency mode provided by the present invention;

[0047] Figure 5 The time domain waveform of the sine sweep signal generated by the signal source;

[0048] Figure 6 This is the first-order bending vibration mode diagram of the test rod generated by the non-contact exciter;

[0049] Figure 7 is the amplitude-frequency characteristic curve of the amplitude response signal;

[0050] Figure 8 Schematic diagram of curve fitting for the maximum amplitude point.

[0051] 1. Signal source; 2-1 and 2-2. Laser vibrometer; 3. Signal acquisition and processing system; 4. Power amplifier; 5. Non-contact vibrator; 6. Display; 7. Measuring support device; 7-1. Test rod; 7-2. Slide rail; 7-3. Ruler; 7-4. Movable slide; 7-5. Transition connector; 7-6. Adjustable fastener; 7-7. Support clamp. DETAILED DESCRIPTION

[0052] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0053] Example 1

[0054] See also Figure 1-3 Embodiment 1 of the present invention provides a dynamic Young's modulus measurement device based on a sweep frequency mode, comprising: a signal source 1; laser vibrometers 2-1 and 2-2; a signal acquisition and processing system 3; a power amplifier 4; a non-contact exciter 5; a display 6; and a measurement support device 7.

[0055] See also Figure 1 The signal source is connected to the power amplifier and the laser vibrometer respectively; the power amplifier is connected to the non-contact vibrator, the laser vibrometer is connected to the signal acquisition and processing system, and the signal acquisition and processing system is connected to the display.

[0056] Specifically, the signal source is used to generate a swept frequency excitation signal within a specific frequency range and send it to the power amplifier, and simultaneously provide a trigger signal to the non-contact exciter for synchronous measurement.

[0057] The specific frequency range is any sub-range of 1 Hz-10 kHz. For example, the frequency sweep excitation signal may be a sine frequency sweep signal of 100 Hz-10 kHz. The frequency sweep rate may be adjusted according to the measurement accuracy requirement.

[0058] The power amplifier is used to amplify the swept frequency excitation signal to a suitable amplitude and then send it to the non-contact vibrator, thereby providing sufficient driving energy for the non-contact vibrator.

[0059] Furthermore, the non-contact exciter uses an electromagnetic or piezoelectric transducer to apply an excitation force to the test rod through acoustic wave coupling, causing the test rod to generate bending vibration, thereby avoiding interference to the test rod caused by direct contact.

[0060] The laser vibrometer utilizes laser Doppler vibrometer technology, using laser wavelengths in the visible light band, near-infrared band, or a combination thereof. It is suitable for non-contact vibration measurement of the test rod, with a laser wavelength range of 500nm to 600nm. The laser vibrometer non-contactly measures the vibration response data of the test rod under swept-frequency excitation and transmits this vibration response data to a signal acquisition and processing system, achieving measurement accuracy down to the micron level.

[0061] The signal acquisition and processing system includes a high-speed data acquisition card and a computer, with an acquisition frequency of not less than 100kHz and a resolution of not less than 16 bits, and is used to perform spectrum analysis and Young's modulus value calculation on the collected vibration response data.

[0062] The test rod in the present invention can be made of the titanium alloy TC4 to be tested, has standardized dimensions, and can be circular or rectangular in cross-section. The measurement support device can adopt a simply supported beam or a cantilever beam support method, and this support method can be modified or selected according to the specific processing equipment.

[0063] As an example, Figure 3 This diagram shows the structure of a simply supported beam measurement support device. The device includes a test rod 7-1, a slide rail 7-2, a scale 7-3, a movable slide 7-4, a transition piece 7-5, an adjustable fastener 7-6, and a support clamp 7-7. The support clamp and the test rod form a point-to-point contact, with the adjustable fastener adjusting the contact strength to ensure ideal boundary conditions for the test rod.

[0064] Continue to see Figure 4 The present invention provides a dynamic Young's modulus measurement method based on a frequency sweep mode, which specifically includes:

[0065] Step 1: Make the material to be tested into a standard test rod and install it on the measurement support device.

[0066] Before step 1, perform system initialization and parameter settings.

[0067] Specifically, it includes: setting the sweep parameters, including the starting frequency f1, the ending frequency f2, and the sweep rate r; setting the sampling parameters, including the sampling frequency fs and the number of sampling points N.

[0068] In this embodiment, the test rod is installed to ensure that the boundary conditions meet the requirements of the theoretical model. After the test rod is installed, the relative distance between the non-contact vibrator and the laser vibrometer and the test rod is adjusted on the optical experimental platform to optimize the measurement effect.

[0069] Next, calibrate the system using standard samples.

[0070] Step 2: Generate a sweep frequency excitation signal within a specific frequency range through a signal source. The sweep frequency excitation signal is amplified by a power amplifier and then input into a non-contact vibrator. The non-contact vibrator performs sweep frequency excitation on the test rod.

[0071] See also Figure 5 , the signal source generates a sine sweep signal with a frequency of f1 = 100 Hz to f2 = 2000 Hz and a sweep duration of T = 5s:

[0072]

[0073] Where: x(t) is the instantaneous signal value at time t; A is the signal amplitude; f1 is the starting frequency (unit: Hz); f2 is the ending frequency (unit: Hz); T is the sweep duration (unit: s); t is the time (unit: s), which usually varies in the range of 0 ≤ t ≤ T; ln represents the natural logarithm.

[0074] In this embodiment, the non-contact exciter applies an excitation force to the test rod by acoustic wave coupling, causing the test rod to generate bending vibration. The first-order bending vibration mode of the test rod generated by the non-contact exciter is shown in FIG. Figure 6 .

[0075] Step 3: Measure the vibration response data of the test rod under the sweep frequency excitation by using a laser vibrometer, and send the vibration response data to the signal acquisition and processing system.

[0076] Step 4: Perform spectrum analysis on the vibration response data through a signal acquisition and processing system to obtain an amplitude response spectrum.

[0077] In this embodiment, the signal acquisition and processing system performs fast Fourier transform on the collected vibration response data to obtain an amplitude response spectrum.

[0078] Step 5: Identify at least one resonance frequency corresponding to a bending vibration resonance peak from the amplitude response spectrum.

[0079] Wherein, the above-mentioned resonant frequency is the first-order bending vibration frequency.

[0080] For details, see Figure 7 , the frequency corresponding to the amplitude maximum point in the amplitude response spectrum can be used as the resonant frequency fn; alternatively, a curve fitting can be performed on the spectrum data near the amplitude maximum point in the amplitude response spectrum, and the resonant frequency fn can be estimated based on the fitting curve, see Figure 8 .

[0081] Step 6: Calculate the Young's modulus of the material according to the resonant frequency and the size and mass of the test rod.

[0082] For the cylindrical rod with simply supported beam boundary conditions in this embodiment, according to the theory of material mechanics, the calculation formula of Young's modulus E is:

[0083]

[0084] Where m is the material mass, L is the length of the test rod, and f n is the measured bending vibration frequency, and d is the diameter of the test rod.

[0085] It should be noted that the Young's modulus measurement method and device provided by the present invention are applicable to test rods of different cross-sectional shapes and vibration modes under various boundary conditions. For a rectangular cross-sectional rod with a simply supported beam boundary condition, the Young's modulus calculation formula in step 6 is:

[0086]

[0087] Where m is the material mass, L is the length of the test rod, and f n is the measured first-order bending vibration frequency, h is the thickness of the test rod, and b is the width of the test rod.

[0088] For a circular cross-section rod with a cantilever beam boundary condition, the Young's modulus in step 6 is calculated as follows:

[0089]

[0090] Where ρ is the material density, L is the length of the test rod, and f n is the measured first-order bending vibration frequency, and d is the diameter of the test rod.

[0091] For a rectangular cross-section rod with a cantilever beam boundary condition, the Young's modulus in step 6 is calculated as follows:

[0092]

[0093] Where ρ is the material density, L is the length of the test rod, and f n is the measured first-order bending vibration frequency, and h is the thickness of the rectangular test rod.

[0094] Step 7: Determine whether the obtained Young's modulus value is within the preset standard range [Emin, Emax], and present the measurement result on the display.

[0095] If Emin≤E≤Emax, the material is judged to meet the standard; otherwise, the material is judged to not meet the standard.

[0096] Example 2

[0097] This embodiment 2 is intended to illustrate the specific application of the present invention in the field of high-end medical device manufacturing, especially for the "Swiss CNC lathe" (abbreviated as "Swiss CNC machine") when processing precision bars such as titanium alloy, to achieve online measurement and monitoring of the material's Young's modulus performance.

[0098] During the machining process of a Swiss-type lathe, a long bar will extend from the guide sleeve. The extended portion can be approximately equivalent to a cantilever beam with one end fixed and the other end free in a physical model. This embodiment 2 utilizes this naturally formed cantilever beam boundary condition to integrate the measuring device of the present invention next to the Swiss-type lathe, realizing online measurement of the Young's modulus of the bar being processed. In other words, the measurement mechanism and method of the present invention achieve the continuity of the machining and measurement processes, and the performance of the bar can be measured as soon as the bar is processed, thereby improving production efficiency.

[0099] Step 1. System configuration and installation

[0100] Prepare a TC4 titanium alloy bar (circular cross-section) to be machined, with a known diameter d (e.g., d = 5 mm). This bar itself serves as the "test bar" and requires no additional preparation. The measurement support is a guide sleeve from a Swiss-type lathe, which serves as the fixed end of the cantilever beam. Clamping the guide sleeve provides a stable and reliable fixed boundary condition.

[0101] Before machining, the Swiss-type lathe extends the bar beyond the guide sleeve by a specific length. This length is the effective cantilever beam length, L. This length can be precisely controlled and read by the machine's CNC system, or accurately measured by external methods such as laser displacement sensors.

[0102] The material density of TC4 titanium alloy can be measured in advance by known methods (e.g. 4500 kg / m 3 ) and pre-input into the signal acquisition and processing system. Specific equipment, such as a non-contact vibrator, can be installed inside the machine tool's protective cover and aimed near the free end of the protruding bar. This ensures that the excitation sound waves effectively act on the bar without physical contact with the bar or machine components. A laser vibrometer is also installed inside the machine tool, with its laser spot aimed at or near the free end of the bar to capture the maximum vibration response.

[0103] The measurement process can be automatically performed during the machine tool's machining intervals (for example, when the bar is re-positioned after one part is cut off and before the next part is machined).

[0104] Step 2: The signal source generates a sweep frequency signal within a preset frequency range (e.g., 200 Hz to 5000 Hz for a 200 mm rod). This signal is amplified by a power amplifier and then drives a non-contact vibrator to perform non-contact sweep frequency excitation on the free end of the titanium alloy rod.

[0105] Step 3: The laser vibrometer measures the vibration velocity or displacement of the bar under excitation in real time, and transmits the response data containing vibration information to the signal acquisition and processing system.

[0106] Step 4: The signal acquisition and processing system performs a fast Fourier transform (FFT) on the received time-domain vibration data to generate an amplitude response spectrum.

[0107] Step 5: The system automatically identifies the peak with the largest amplitude in the spectrum. The frequency corresponding to this peak is the first-order bending vibration resonant frequency of the titanium alloy bar in the cantilever beam state. To improve accuracy, the aforementioned curve fitting method can be used to fit the data near the peak point, resulting in a more accurate estimate.

[0108] Step 6: The system calculates the Young's modulus value of the material according to the resonant frequency and the size and mass of the test rod.

[0109] For the circular cross-section rod with the cantilever beam boundary condition in Example 2, the calculation formula of the Young's modulus in step 6 is:

[0110]

[0111] Where ρ is the material density, L is the effective length of the cantilever beam, and f n is the measured first-order bending vibration frequency, and d is the diameter of the test rod.

[0112] Step 7: The signal acquisition and processing system compares the calculated Young's modulus value with the standard preset Young's modulus range for that grade of titanium alloy (e.g., 106 GPa ± 1%). The measurement results and judgment (pass or fail) are displayed in real time on the monitor and can be recorded in the quality control database.

[0113] If the measured value exceeds the preset range, the system can trigger an alarm to prompt the operator to pay attention to the quality stability of the batch of bars; it can even be linked with the machine tool control system to suspend processing or isolate the parts processed using this section of material, thereby avoiding quality consistency problems in the final product due to abnormal material properties.

[0114] The technical solutions of the above embodiments utilize non-contact excitation and laser vibration measurement techniques, combined with swept-frequency excitation and spectrum fitting analysis, to achieve rapid and accurate measurement of a material's dynamic Young's modulus. The measurement process is highly automated, making it suitable for industrial online testing applications. Furthermore, the measuring device of the present invention utilizes a flexible and adaptable support structure, allowing for precise measurement of test rods of varying shapes (e.g., circular or rectangular cross-sections), simplifying device design and reducing operational complexity.

[0115] Note that the above are only preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the concept of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. A dynamic Young's modulus measurement method based on a frequency sweep mode, characterized in that: include Step 1: Make the material to be tested into a standard test rod and install it on the measurement support device; Step 2: Generate a sweep frequency excitation signal within a specific frequency range through a signal source, amplify the sweep frequency excitation signal through a power amplifier, and then input it into a non-contact vibrator, which performs sweep frequency excitation on the test rod; Step 3: measuring the vibration response data of the test rod under the sweep frequency excitation by a laser vibrometer, and sending the vibration response data to a signal acquisition and processing system; Step 4: Performing spectrum analysis on the vibration response data through a signal acquisition and processing system to obtain an amplitude response spectrum; Step 5: identifying at least one resonant frequency corresponding to a bending vibration resonance peak from the amplitude response spectrum; Step 6: Calculate the Young's modulus of the material based on the resonant frequency, the geometry and physical parameters of the test rod, and the corresponding vibration mode.

2. The method according to claim 1, characterized in that The specific frequency range is any sub-range between 1 Hz and 10 kHz.

3. The method according to claim 1, characterized in that The non-contact vibrator applies an excitation force to the test rod in a non-contact manner through acoustic wave coupling, causing the test rod to generate bending vibration.

4. The method according to claim 1, wherein The resonant frequency is the first-order bending vibration frequency.

5. The method according to claim 1, characterized in that The step 5 specifically includes: The frequency corresponding to the amplitude maximum point in the amplitude response spectrum is used as the resonant frequency; or, Curve fitting is performed on spectrum data near the amplitude maximum point in the amplitude response spectrum, and the resonant frequency is estimated based on the fitting curve.

6. The method according to claim 1, wherein The step 6 comprises: When the test rod is a circular cross-section rod with simply supported beam boundary conditions, the Young's modulus is calculated as: Where m is the material mass, L is the length of the test rod, and f n is the measured first-order bending vibration frequency, the first-order bending vibration frequency is the resonant frequency measured in step 5, and d is the diameter of the test rod; When the test rod is a rectangular cross-section rod with simply supported beam boundary conditions, the Young's modulus is calculated as: Where m is the material mass, L is the length of the test rod, and f n is the measured first-order bending vibration frequency, h is the thickness of the test rod, and b is the width of the test rod; When the test rod is a circular cross-section rod with cantilever beam boundary conditions, the Young's modulus is calculated as: Where ρ is the material density, L is the length of the test rod, and f n is the measured first-order bending vibration frequency, d is the diameter of the test rod; When the test rod is a rectangular cross-section rod with a cantilever beam boundary condition, the Young's modulus in step 6 is calculated as follows: Where ρ is the material density, L is the length of the test rod, and f n is the measured first-order bending vibration frequency, and h is the thickness of the rectangular test rod.

7. The method according to claim 1, characterized in that After step 6, the method further includes: It is determined whether the obtained Young's modulus value is within the preset standard range, and the measurement result and the judgment result are presented on the display.

8. A dynamic Young's modulus measurement device based on a frequency sweep mode, characterized in that: include: Measurement support device, signal source, power amplifier, non-contact vibrator, laser vibrometer, and signal acquisition and processing system; The signal source is connected to a power amplifier and a laser vibrometer, respectively; the power amplifier is connected to a non-contact vibrator, and the laser vibrometer is connected to a signal acquisition and processing system; the signal source is used to generate a swept frequency excitation signal within a specific frequency range and send it to the power amplifier, and simultaneously provide a trigger signal to the non-contact vibrator; The power amplifier is used to amplify the sweep frequency excitation signal and then send it to the non-contact exciter; The non-contact exciter is used to apply sweep frequency excitation to the test rod; The laser vibrometer is used to measure the vibration response data of the test rod under the sweep frequency excitation and send the vibration response data to the signal acquisition and processing system; The signal acquisition and processing system is used to perform spectrum analysis and Young's modulus value calculation on the collected vibration response data.

9. The device according to claim 8, characterized in that The measurement support device adopts a simply supported beam support method or a cantilever beam support method.

10. The device according to claim 8, characterized in that The laser wavelength used by the laser vibrometer is a visible light band, a near infrared band or a combination thereof.

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