A method for testing the strong field mechanical quality factor of a disk piezoelectric oscillator

Abstract

This invention discloses a method for testing the mechanical quality factor of a disk piezoelectric oscillator under strong field conditions, relating to the field of piezoelectric material performance testing technology. It establishes a comprehensive heat transfer model for the temperature rise generated by the disk piezoelectric oscillator under resonant conditions; establishes the relationship between the heating parameters, vibration velocity, and mechanical quality factor of the piezoelectric disk oscillator; obtains the strong field resonant frequency of the disk piezoelectric oscillator; measures the average convective heat transfer coefficient of the disk piezoelectric oscillator; measures the temperature distribution and vibration velocity of the disk piezoelectric oscillator; analyzes the data to derive the corresponding mechanical quality factor; and characterizes the mechanical quality factor by measuring the temperature distribution and vibration of the disk piezoelectric oscillator at resonance. This method better reflects the loss changes of the disk piezoelectric oscillator in actual scenarios and, by analyzing losses from the perspective of heat generation, overcomes the limitations of using high-amplitude input frequency sweep.

Description

Technical Field

[0001] This invention relates to the field of piezoelectric material performance testing technology, specifically to a method for testing the strong field mechanical quality factor of a disk piezoelectric oscillator. Background Technology

[0002] In recent years, power ultrasound has been widely used in the fields of energy, medicine, environmental protection and aerospace, and piezoelectric materials, as the core components of power ultrasound, have also become popular materials.

[0003] Currently, most research on the performance parameters of piezoelectric materials, both domestically and internationally, focuses on weak field conditions. This is inconsistent with the application environment of high-power piezoelectric devices, because piezoelectric materials exhibit significant nonlinear effects when operating under strong field conditions, such as resonance drift, harmonic distortion, and skipping. This inevitably leads to heating, amplitude saturation, and performance degradation in the piezoelectric materials. The strong field nonlinear effects of piezoelectric materials result in significant differences in their performance parameters between strong and weak fields. Under these circumstances, it is difficult to determine the performance parameters of piezoelectric materials, making device design and performance parameter determination quite challenging. Therefore, research on the performance parameters of piezoelectric materials under strong field conditions is particularly important.

[0004] Mechanical quality factor Q m As one of the important parameters of piezoelectric material performance, it mainly reflects the energy consumed by the piezoelectric material to overcome friction during resonance, and to a large extent reflects the quality of the electromechanical conversion performance of the piezoelectric material. At present, the mechanical quality factor can be measured by impedance method and half-power point method (3dB), but it is limited to weak field excitation conditions.

[0005] As mentioned above, the properties of piezoelectric materials under strong field conditions exhibit nonlinear behavior related to the external field. If the excitation electric field is large, traditional methods cannot accurately measure the mechanical quality factor. It is particularly noteworthy that disk piezoelectric oscillators with radial vibration modes are widely used in power ultrasound, but the application of disk piezoelectric oscillators under strong field conditions remains a challenge. Q m Characterization studies of disk piezoelectric oscillators in strong fields are still lacking. Q m The characterization methods of the parameters and their power characteristics warrant further investigation. Therefore, a test method for the strong-field mechanical quality factor of a disk piezoelectric oscillator is proposed to address the above issues. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a method for testing the mechanical quality factor of a disk piezoelectric vibrator in a strong field, thus solving the problems existing in the prior art.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A method for testing the strong field mechanical quality factor of a disk piezoelectric oscillator includes the following steps:

[0009] The disk piezoelectric oscillator sample is divided into multiple micro-elements along the radial direction. Based on the heat flow at the micro-elements, a comprehensive heat transfer model is established to describe the temperature rise caused by the disk piezoelectric oscillator heating up in the resonance state.

[0010] Based on the integrated heat transfer model, the relationship between heat generation parameters, vibration velocity, and mechanical quality factor is established;

[0011] The impedance curve of the disk piezoelectric vibrator sample was measured using an impedance analyzer to obtain the resonant frequency under weak field conditions. Then, the resonant frequency under weak field conditions was finely adjusted using a current probe to obtain the resonant frequency under strong field conditions.

[0012] A sinusoidal AC voltage signal with a strong field resonance frequency is applied to the disk piezoelectric vibrator sample for excitation. The temperature distribution of the disk piezoelectric vibrator sample in steady state is collected. Then, by stopping the excitation of the disk piezoelectric vibrator sample, the temperature change curve of the sample from steady state temperature to room temperature is obtained. Transient analysis is performed on the temperature change curve to obtain the convective heat transfer coefficient of the disk piezoelectric vibrator sample.

[0013] The convective heat transfer coefficient is substituted into the comprehensive heat transfer model and fitted with the steady-state temperature distribution of the disk piezoelectric oscillator sample to obtain the heating parameters.

[0014] A laser vibrometer was used to measure the boundary vibration velocity of a disk piezoelectric vibrator sample that had reached a steady-state temperature after being subjected to a voltage signal, so as to obtain the boundary vibration velocity of the disk piezoelectric vibrator sample when the temperature reached a steady state.

[0015] Substituting the obtained heating parameters and boundary vibration velocity into the formula, the mechanical quality factor under the corresponding conditions is obtained.

[0016] Furthermore, the integrated heat transfer model is as follows: ；

[0017]

[0018] in λ Expressed as thermal conductivity, T( r,t ) Represented as temperature, h The thickness of the disk piezoelectric vibrator cP and ρ These are represented by specific heat capacity and element density, respectively. h d The convective heat transfer coefficient is... T airRepresented as the temperature in the air. Q g (r) represents the heat production per unit volume as a function of the radius.

[0019] Furthermore, the theoretical model relating the heating parameters, vibration velocity, and mechanical quality factor is as follows:

[0020]

[0021] in f r V is the resonant frequency of the sample. RMS The root mean square vibration velocity of the sample is... k For wave vector, J 0(ka) and J1(ka) are the zeroth and first-order Bessel functions, respectively. h g The parameters for body heating.

[0022] Furthermore, the disk piezoelectric oscillator is excited by a voltage signal with a large amplitude and a resonant frequency.

[0023] Furthermore, the frequency of the voltage signal is the strong field resonance frequency of the piezoelectric oscillator, and the peak value of the voltage signal is adjustable.

[0024] Furthermore, the voltage signal is a sinusoidal continuous AC signal or a Tone-Burst pulse signal.

[0025] Furthermore, an infrared thermal imager was used to observe the temperature changes of the sample.

[0026] Furthermore, the mechanical quality factor is calculated using the resonant frequency under the obtained strong field, as well as the heating parameters and vibration velocity:

[0027]

[0028] This invention provides a method for testing the strong-field mechanical quality factor of a disk piezoelectric oscillator, which has the following characteristics:

[0029] Beneficial effects:

[0030] The mechanical quality factor of a disk piezoelectric oscillator is characterized by measuring its temperature distribution and vibration at resonance. This approach better reflects the loss changes of the disk piezoelectric oscillator in real-world scenarios and overcomes the limitations of using high-amplitude input frequency sweep by analyzing the loss from a heat generation perspective. Furthermore, a method using Tone-Burst electric field pulse signals to excite the disk piezoelectric oscillator is proposed, reducing the impact of the piezoelectric disk's temperature rise on the resonant frequency change of the piezoelectric oscillator. Attached Figure Description

[0031] Figure 1 This is a flowchart of the disk piezoelectric vibrator testing method of the present invention;

[0032] Figure 2 This is a schematic diagram showing the geometric dimensions of the disc piezoelectric vibrator of the present invention and the heat flow of the micro-element;

[0033] Figure 3 This is a schematic diagram showing the steady-state temperature rise of the disc piezoelectric vibrator of the present invention as a function of radial position;

[0034] Figure 4 This is a schematic diagram showing the temperature change over time at the center point of the piezoelectric vibrator of the disk according to the present invention;

[0035] Figure 5 This is a schematic diagram showing the fitting of the temperature rise curve of the disc piezoelectric vibrator of the present invention from steady-state temperature to room temperature with the theoretical curve;

[0036] Figure 6 This is a schematic diagram of the Tone-Burst pulse excitation electric field of the present invention;

[0037] Figure 7 This is a schematic diagram showing the fitting between the experimental temperature value and the theoretical temperature value of this invention;

[0038] Figure 8 This is a schematic diagram showing the change of the mechanical quality factor of the disc piezoelectric vibrator of the present invention with vibration velocity;

[0039] Figure 9 This is a schematic diagram of the experimental apparatus for testing the mechanical quality factor of a disc piezoelectric vibrator under a strong field according to the present invention. Detailed Implementation

[0040] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0041] like Figure 1 The method for testing the strong field mechanical quality factor of the disc piezoelectric oscillator shown includes the following steps:

[0042] A comprehensive heat transfer model is established for the temperature rise caused by the heating of a disk piezoelectric oscillator in a resonant state.

[0043] Establish the relationship between the heating parameters, vibration velocity, and mechanical quality factor of the piezoelectric disk oscillator;

[0044] Obtain the strong field resonance frequency of the disk piezoelectric oscillator;

[0045] Measure the average convective heat transfer coefficient of the disc piezoelectric vibrator;

[0046] The steady-state temperature distribution of the disk piezoelectric oscillator was measured, and the heating parameters were obtained by fitting the steady-state temperature distribution of the sample to the integrated heat transfer model.

[0047] Measuring the vibration velocity of a disk-type piezoelectric vibrator;

[0048] Analyze the data to derive the corresponding mechanical quality factor;

[0049] A comprehensive heat transfer model is established for the temperature rise caused by the heating of the disk piezoelectric oscillator in the resonant state. This step also includes the following:

[0050] First, divide the piezoelectric disk oscillator into N equal parts along the radial direction;

[0051] Analyze the heat flow at a specific infinitesimal element. For example... Figure 2 The geometry of the disk piezoelectric oscillator and the heat flow through the infinitesimal element are shown in the figure. The heat flow through the infinitesimal element can be divided into four parts: heat flowing from the previous infinitesimal element... Q c,r Heat flowing to the next infinitesimal Q c,r+dr Heat transferred by convection with air Q d,r The heat generated by the vibration of the infinitesimal element itself Q g,r Combining Figure 1 Based on the law of conservation of energy, the following equation can be written:

[0052]

[0053] By expressing the four heat flow and heat energy changes of the infinitesimal element and substituting them into the above equation, we can obtain the corresponding heat conduction equation:

[0054]

[0055] in λ Expressed as thermal conductivity, T( r,t ) Represented as temperature, h The thickness of the disk piezoelectric vibrator cP and ρ These are represented by specific heat capacity and element density, respectively. h d The convective heat transfer coefficient is... T air Represented as the temperature in the air. Q g(r) represents the heat generation per unit volume as a function of radius. To more intuitively and accurately describe the heat conduction model of the disk piezoelectric oscillator, the disk piezoelectric oscillator can be divided into three parts: the center, the area from the center to the boundary, and the boundary itself. The heat conduction equation can be rearranged using the finite difference method to obtain:

[0056]

[0057] Where 0, i, and N represent the positions of the disk piezoelectric oscillator. Since the heat distribution of the disk piezoelectric oscillator is proportional to the square of the strain distribution, then...

[0058]

[0059] in J 0(kr) represents the shape of the strain distribution along the radial direction of the piezoelectric disc, and J 0(kr) represents the zeroth-order Bessel function, where c represents the elastic wave velocity propagating along the radial direction.

[0060] like Figure 3 The diagram shows the steady-state temperature rise of a disk piezoelectric vibrator as a function of its radial position.

[0061] like Figure 4 The diagram shows the temperature change at the center point of the piezoelectric oscillator over time.

[0062] The method for establishing the relationship between the heating parameters, vibration velocity, and mechanical quality factor of a disk-type piezoelectric oscillator also includes the following:

[0063] By definition, the mechanical quality factor is the ratio of the mechanical energy to the power dissipation of a piezoelectric oscillator.

[0064]

[0065] U e P is expressed as the mechanical energy of a piezoelectric element. d Expressed as dissipated energy, and due to the nonlinear flexibility of piezoelectric materials, mechanical energy is defined using maximum kinetic energy, and maximum velocity is expressed as:

[0066]

[0067] The maximum kinetic energy can then be written in the following form:

[0068]

[0069] Where 'a' is the radius of the disk piezoelectric oscillator. When the disk piezoelectric oscillator reaches thermal steady state, the convective power dissipation equals the heat at steady state, and the dissipated power can be expressed as:

[0070]

[0071] Substituting the expressions for kinetic energy and dissipated power into the definition of the mechanical quality factor, we can obtain...

[0072]

[0073] Where f r V is the resonant frequency of the sample. RMS Let be the root mean square vibration velocity of the sample, k be the wave vector, J0(ka) and J1(ka) be the zeroth and first order Bessel functions, respectively, and h be the wave vector. g The parameters for body heating.

[0074] The methods for obtaining the strong field resonant frequency of a disk piezoelectric oscillator also include the following;

[0075] Before obtaining the resonant frequency of the piezoelectric disk oscillator, first ensure that the thickness-to-diameter ratio of the selected piezoelectric disk oscillator sample is approximately 1 / 10; secondly, clarify the parameters of the selected piezoelectric disk oscillator; finally, calculate the theoretical resonant frequency value of the selected piezoelectric disk oscillator sample using theoretical formulas.

[0076] Then, based on the calculated theoretical resonance frequency, the measurement range of the impedance spectrum of the impedance analyzer is determined, and the resonance frequency of the weak field of the disk piezoelectric oscillator sample is obtained by analyzing the impedance curve measured by the impedance analyzer.

[0077] Apply a large-amplitude sinusoidal AC signal to both ends of the disc piezoelectric vibrator sample, and the excitation frequency is the resonant frequency when the field is weak. Keep the voltage applied to both ends of the sample constant and fine-tune the excitation frequency. Then, feed the current signal at both ends of the sample back to the oscilloscope through the current probe and observe the current signal at both ends of the sample. When the current value reaches its maximum, stop fine-tuning the frequency. The frequency value at this time is the resonant frequency of the sample when the field is strong.

[0078] In one embodiment, the strong-field resonant frequency of the disk piezoelectric oscillator can also be obtained using a laser vibrometer. The specific method is as follows: keep the voltage signal with a large amplitude at both ends of the sample unchanged, use the resonant frequency as a reference value, fine-tune the frequency value, observe the magnitude of the sample's vibration velocity, and stop changing the frequency value when the sample's vibration velocity reaches its maximum. Then, the finely adjusted frequency value is the resonant frequency of the sample in a strong field.

[0079] The measurement steps for the average convective heat transfer coefficient of a disc piezoelectric vibrator are as follows:

[0080] The disk piezoelectric oscillator sample is excited by a voltage signal with an excitation frequency equal to the resonant frequency and a large amplitude.

[0081] Simultaneously, the temperature change of the sample is observed using an infrared thermal imager. Once the sample reaches a steady state, the input voltage signal to the sample is stopped.

[0082] Record the temperature rise data of the sample from steady state temperature to room temperature, and plot its temperature rise curve;

[0083] The convective heat transfer coefficient of the sample can be obtained by fitting the temperature rise curve obtained through experiments.

[0084] In one embodiment, the functional expression required to fit the temperature rise curve of the convective heat transfer coefficient is:

[0085]

[0086] in T air Represents the temperature of the surrounding environment. T ini The temperature representing the sample, let A represents the sample surface area. ρ V represents the sample density, and V represents the sample volume. C P The specific heat capacity of the representative sample h d This is the convective heat transfer coefficient. For example... Figure 5 The figure shows a schematic diagram of the fitting of the temperature rise curve of a certain disk piezoelectric oscillator from steady state temperature to room temperature.

[0087] The method for measuring the temperature distribution and vibration velocity of a disk piezoelectric vibrator includes the following steps:

[0088] Apply a sinusoidal AC voltage signal with the resonant frequency to both ends of the disc piezoelectric vibrator sample, and ensure that the applied voltage signal has a certain temperature rise.

[0089] Observe the temperature rise of the sample after the voltage signal is applied, wait for it to reach the steady-state temperature and record the sample temperature at this time, and record the vibration velocity of the sample at this time.

[0090] Increase the amplitude of the sinusoidal AC signal at the same intervals and repeat the above steps;

[0091] When the temperature rise of the disk piezoelectric vibrator exceeds 20°C above room temperature, stop increasing the voltage amplitude and end the measurement process.

[0092] Because the temperature rise of the disk-shaped piezoelectric oscillator sample is particularly significant under continuous sinusoidal AC voltage excitation, in order to minimize the impact of sample heating on piezoelectric material parameters such as resonant frequency, this invention also proposes to excite the sample using a Tone-Burst pulse signal, wherein... Figure 6 This is a schematic diagram of the Tone-Burst pulse signal.

[0093] When exciting the sample with a Tone-Burst pulse signal, the measurement process is the same as that for measuring the temperature distribution and vibration velocity of the disk piezoelectric oscillator in the example above. Furthermore, the maximum temperature rise of the sample can be kept below 20 degrees Celsius by changing the duty cycle of the Tone-Burst pulse signal during the test. This method can increase the electric field applied across the sample.

[0094] The duty cycle of the Tone-Burst pulse signal is the period of each Tone-Burst pulse signal divided by the repetition period of the Tone-Burst pulse signal.

[0095] The methods for analyzing experimental data to derive the corresponding mechanical quality factor include the following:

[0096] When analyzing the temperature distribution curve of a disk piezoelectric vibrator sample, the surrounding air is also heated when the disk piezoelectric vibrator vibrates and generates heat, so it is necessary to determine the boundary temperature of the sample.

[0097] The highest point of the measured temperature distribution curve is selected as the temperature at the center of the sample circle. The temperature from the center to the boundary is recorded. The experimentally measured temperature data from the center to the boundary is fitted with the theoretical value to obtain the corresponding heating parameters. The measured vibration velocity value is converted into the root mean square form.

[0098] Substitute the fitted heating parameters and root mean square vibration velocity into the established relationship between heating parameters, vibration velocity, and mechanical quality factor:

[0099]

[0100] From this, the mechanical quality factor under the corresponding conditions can be obtained. Figure 7 This is a graph showing the fitting relationship between theoretical and experimental temperature values ​​for a given voltage amplitude.

[0101] During the above measurement process, since the voltage amplitude applied across the disc piezoelectric oscillator varies, while the impedance of the sample at the resonant frequency remains constant, the current applied across the sample varies with the voltage. Furthermore, because the vibration velocity of the sample is proportional to the current applied across it, and the disc piezoelectric oscillator primarily exhibits its vibration characteristics in the resonant state, its performance can be reflected by observing the changing trends of vibration velocity and mechanical quality factor. Figure 8 This is a graph showing the relationship between the mechanical quality factor of the disc piezoelectric vibrator and the vibration velocity during the measurement process.

[0102] Furthermore, this invention also provides a testing device corresponding to the method for testing the strong field mechanical quality factor of a disk piezoelectric oscillator, such as... Figure 9The diagram shown is of a testing apparatus, which includes:

[0103] A function generator is used to output the desired waveform signal to the sample.

[0104] A power amplifier, used to amplify its voltage signal;

[0105] A laser vibrometer is used to collect the vibration velocity of a sample when it is excited.

[0106] Infrared thermal imagers are used to acquire temperature signals from samples.

[0107] An oscilloscope is used to collect the actual voltage signal across the sample.

[0108] A computer terminal used to collect data on vibration velocity and temperature.

[0109] The function generator is connected to the power amplifier. The function generator adjusts the signal required for the experiment and transmits the signal to the power amplifier. The power amplifier amplifies the signal and applies it to both sides of the disk piezoelectric oscillator to ensure that the sample works under strong field conditions.

[0110] The laser vibrometer and the infrared thermal imager are connected to the computer terminal. The laser vibrometer mainly detects the vibration signal of the sample and then feeds the vibration signal back to the computer terminal. In addition, the laser vibrometer can also be directly connected to an oscilloscope to observe the voltage signal in the oscilloscope to feed back the vibration signal of the sample. The infrared thermal imager mainly detects the temperature change of the sample surface and feeds the temperature signal back to the computer terminal.

[0111] The two ends of the sample are connected to an oscilloscope to receive the actual voltage values ​​applied to the two ends of the sample.

[0112] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for testing the strong field mechanical quality factor of a disk piezoelectric oscillator, characterized in that, Includes the following steps: The disk piezoelectric oscillator sample is divided into multiple micro-elements along the radial direction. Based on the heat flow at the micro-elements, a comprehensive heat transfer model is established to describe the temperature rise caused by the disk piezoelectric oscillator heating up in the resonance state. Based on the integrated heat transfer model, the relationship between heat generation parameters, vibration velocity, and mechanical quality factor is established; The impedance curve of the disk piezoelectric vibrator sample was measured using an impedance analyzer to obtain the resonant frequency under weak field conditions. Then, the resonant frequency under weak field conditions was finely adjusted using a current probe to obtain the resonant frequency under strong field conditions. A sinusoidal AC voltage signal with a strong field resonance frequency is applied to the disk piezoelectric vibrator sample for excitation. The temperature distribution of the disk piezoelectric vibrator sample in steady state is collected. Then, by stopping the excitation of the disk piezoelectric vibrator sample, the temperature change curve of the sample from steady state temperature to room temperature is obtained. Transient analysis is performed on the temperature change curve to obtain the convective heat transfer coefficient of the disk piezoelectric vibrator sample. The obtained convective heat transfer coefficients were substituted into the comprehensive heat transfer model, and the steady-state temperature distribution of the disc piezoelectric oscillator sample was fitted to obtain the heating parameters. A laser vibrometer was used to measure the boundary vibration velocity of a disk piezoelectric vibrator sample that had reached a steady-state temperature after being subjected to a voltage signal, so as to obtain the boundary vibration velocity of the disk piezoelectric vibrator sample when the temperature reached a steady state. Substituting the obtained heating parameters and boundary vibration velocity into the formula, the mechanical quality factor under the corresponding conditions is obtained.

2. The method for testing the strong field mechanical quality factor of a disk piezoelectric oscillator according to claim 1, characterized in that, Divide the piezoelectric disk oscillator into multiple infinitesimal elements along the radial direction, analyze the heat flow at a certain infinitesimal element, and derive the equation based on the law of conservation of energy: in, Q c,r It's the heat flowing from the previous microelement. Q c,r+dr It is the heat flowing to the next microelement. Q d,r It consists of heat transferred through convection with the air and heat generated by the vibration of the infinitesimal element itself. Q g,r ; The four heat flux and heat energy changes of this infinitesimal element are expressed as expressions and substituted into the equations to obtain the comprehensive heat transfer model: in λ Expressed as thermal conductivity, T ( r,t () represents temperature. h The thickness of the disk piezoelectric vibrator, c P and ρ These are represented by specific heat capacity and element density, respectively. h d The convective heat transfer coefficient is... T air Represented as the temperature in the air. Q g ( r ) represents the heat production per unit volume as a function of the radius.

3. The method for testing the strong field mechanical quality factor of a disk piezoelectric oscillator according to claim 2, characterized in that, The piezoelectric oscillator of the disk is divided into three parts: the center, the area from the center to the boundary, and the boundary. The resulting integrated heat transfer model is then rearranged using a finite difference method to obtain the following: Where 0 represents the position of the center of the disk piezoelectric vibrator. i The distance from the center to the boundary of the disk-shaped piezoelectric vibrator. N This represents the boundary of the disk piezoelectric oscillator.

4. The method for testing the strong field mechanical quality factor of a disk piezoelectric oscillator according to claim 3, characterized in that, Based on the relationship that the heat distribution of a disk piezoelectric oscillator is proportional to the square of its strain distribution, we obtain: in This represents the shape of the strain distribution along the radial direction of the piezoelectric disc, and Represented as a zero-order Bessel function, where , c It is expressed as the elastic wave velocity propagating along the radial direction.

5. The method for testing the strong field mechanical quality factor of a disk piezoelectric oscillator according to claim 2, characterized in that, Based on the heat transfer model, the relationship between the heating parameters, vibration velocity, and mechanical quality factor is as follows: in f r The resonant frequency of the sample. V RMS The root mean square vibration velocity of the sample is given. k Let J0 be the wave vector. ka ), J1 ( ka These are the zeroth and first-order Bessel functions, respectively. h g The parameters for body heating.

6. The method for testing the strong field mechanical quality factor of a disk piezoelectric oscillator according to claim 1, characterized in that, Before obtaining the resonant frequency of the disk piezoelectric vibrator, it is necessary to ensure that the thickness to diameter ratio of the selected disk piezoelectric vibrator sample is about 1 / 10.

7. The method for testing the strong field mechanical quality factor of a disk piezoelectric oscillator according to claim 1, characterized in that, The function expression corresponding to the temperature rise curve is: in T air Represents the temperature of the surrounding environment. T ini The temperature representing the sample, let , Represents the sample surface area. ρ Represents the sample density. V Represents the sample volume. C P The specific heat capacity of the representative sample h d is the convective heat transfer coefficient.

8. The method for testing the strong field mechanical quality factor of a disk piezoelectric oscillator according to claim 1, characterized in that, The expression for the mechanical quality factor, calculated using the resonant frequency under the strong field, heating parameters, and boundary vibration velocity, is as follows: 。

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