CN116626167A - Ultrasonic transverse wave attenuation coefficient measuring device and working method - Google Patents

Abstract

The invention provides a measuring device and a working method of an ultrasonic transverse wave attenuation coefficient, wherein the device comprises the following components: the ultrasonic detector is used for exciting the ultrasonic transverse wave probe to generate ultrasonic transverse waves, recording echo amplitude of the transverse waves on the reflecting surfaces of the test block and the workpiece to be tested, and sequentially calculating the absorption attenuation coefficient, the scattering attenuation coefficient and the diffusion attenuation coefficient of the workpiece to be tested according to the amplitude; the ultrasonic transverse wave probe is used for being fixed on the coupling surface of the test block or the workpiece to be tested, and transmitting and receiving ultrasonic transverse waves; the test block is designed according to the material property of the workpiece to be tested and the attenuation characteristic of the ultrasonic transverse wave, and is used for receiving the ultrasonic transverse wave and forming an echo on the reflecting surface. According to the invention, the influence of diffusion attenuation in attenuation coefficient measurement is eliminated through the pre-designed test block, the absorption attenuation coefficient, the scattering attenuation coefficient and the diffusion attenuation coefficient of the workpiece to be measured are sequentially calculated, the diffusion attenuation coefficient matched with the shape and the size of the workpiece to be measured is obtained, and the accuracy of ultrasonic transverse wave attenuation coefficient measurement is improved.

Description

A measuring device and working method for ultrasonic shear wave attenuation coefficient

Technical Field

The invention relates to the technical field of ultrasonic shear wave attenuation coefficient measurement, and in particular to a device and a working method for measuring the ultrasonic shear wave attenuation coefficient.

Background Art

When ultrasonic waves propagate in a medium, the diffusion attenuation caused by the diffusion of the ultrasonic sound beam itself, the absorption attenuation caused by the absorption of ultrasonic energy by the medium, and the scattering attenuation caused by the scattering of ultrasonic waves by the grain boundaries between the medium grains will all lead to the decrease of the energy of ultrasonic waves in the process of propagation in the medium. Generally, the attenuation coefficient of ultrasonic waves is the sum of the diffusion attenuation coefficient, the absorption attenuation coefficient and the scattering attenuation coefficient. Obtaining the attenuation coefficient of ultrasonic waves is important for understanding the attenuation law of ultrasonic sound fields in the medium and for qualitatively and quantitatively determining defects in the medium.

At present, the ultrasonic shear wave attenuation coefficient generally uses a thin plate specimen of the same material or similar material as the workpiece to be tested. After the ultrasonic shear wave is obliquely incident into the thin plate specimen, it reflects back and forth between the bottom surface of the thin plate specimen and the coupling surface. By setting a receiving probe at a span of n times (n=1, 2, 3, ...) of the coupling surface, the sound pressure of the ultrasonic shear wave after n reflections is obtained, thereby obtaining the attenuation coefficient of the ultrasonic shear wave in the thin plate. The attenuation coefficient measured by this method is the sum of the diffusion attenuation coefficient, the absorption attenuation coefficient and the scattering attenuation coefficient. It is impossible to measure the value of each attenuation coefficient, especially the diffusion attenuation coefficient is greatly affected by the shape and size of the workpiece to be tested. The diffusion attenuation coefficient measured on the thin plate specimen often cannot represent the diffusion attenuation coefficient in the workpiece to be tested.

Summary of the invention

Therefore, the technical problem to be solved by the present invention is to overcome the shortcoming of inaccurate measurement of the ultrasonic shear wave attenuation coefficient in the prior art, thereby providing a measuring device and working method for the ultrasonic shear wave attenuation coefficient, which can measure the diffusion attenuation coefficient, scattering attenuation coefficient and absorption attenuation coefficient of the ultrasonic shear wave of the workpiece to be tested with different shapes and sizes, and improve the accuracy of the attenuation coefficient measurement of the workpiece to be tested.

The technical solution of the present invention to solve the above technical problems is as follows:

In a first aspect, the present invention provides a device for measuring ultrasonic shear wave attenuation coefficient, the system comprising: an ultrasonic detector, an ultrasonic shear wave probe, and a preset number of test blocks;

The ultrasonic detector is used to excite the ultrasonic shear wave transmitting probe to generate ultrasonic shear waves of a preset frequency, and record the echo amplitudes formed by the ultrasonic shear waves received by the ultrasonic shear wave receiving probe on the reflection surfaces of the test block and the workpiece to be tested, and calculate the absorption attenuation coefficient, scattering attenuation coefficient and diffusion attenuation coefficient of the workpiece to be tested in sequence according to the amplitudes;

The ultrasonic shear wave probe comprises an ultrasonic shear wave transmitting probe and an ultrasonic shear wave receiving probe, which are used to be fixed on the coupling surface of the test block or the workpiece to be tested. The ultrasonic shear wave transmitting probe is excited by the ultrasonic detector to generate ultrasonic shear waves and transmits them, and the ultrasonic shear wave receiving probe receives the echo of the ultrasonic shear wave and returns it to the ultrasonic detector.

The test block is designed according to the material properties of the workpiece to be tested and the attenuation characteristics of the ultrasonic shear wave, so that the ultrasonic shear wave propagates inside it and forms an echo on the reflection surface. The echo is used to calculate the absorption attenuation coefficient, scattering attenuation coefficient and diffusion attenuation coefficient of the workpiece to be tested;

The test blocks include: a preset number of semi-cylindrical test blocks or a preset number of isosceles trapezoidal test blocks, the surface roughness, acoustic impedance and material of the semi-cylindrical test blocks or isosceles trapezoidal test blocks are the same as those of the workpiece to be tested;

The cylindrical surface radius of each of the semi-cylindrical test blocks is the same and is set to be greater than a preset multiple of the near field area of the ultrasonic shear wave probe, the surface roughness is set to be less than a first preset ratio of the shear wave wavelength, and the average grain size of each of the semi-cylindrical test blocks is different from each other and is set to be less than a second preset ratio of the shear wave wavelength;

The distance between the isosceles trapezoidal surface of each of the isosceles trapezoidal test blocks and the ultrasonic shear wave incident point is the same, and is set to be greater than a preset multiple of the near field area of the ultrasonic shear wave probe. The surface roughness is set to be less than a first preset proportion of the shear wave wavelength. The average grain size of each of the isosceles trapezoidal test blocks is different from each other and is set to be less than a second preset proportion of the shear wave wavelength.

The ultrasonic shear wave attenuation coefficient measuring device provided by the embodiment of the present invention is designed in advance according to the material properties of the workpiece to be tested and the attenuation characteristics of the ultrasonic shear wave. A semi-cylindrical test block and an isosceles trapezoidal test block are used as test blocks. The ultrasonic shear wave transmitting probe fixed on each test block or the coupling surface of the workpiece to be tested is excited by an ultrasonic detector to generate an ultrasonic shear wave of a preset frequency, and the ultrasonic shear wave is transmitted to the corresponding reflection surface. The ultrasonic shear wave forms an echo between the coupling surface and the reflection surface. The ultrasonic shear wave receiving probe receives the preset number of reflected echoes and the ultrasonic detector records the amplitude of each echo. The absorption attenuation coefficient, scattering attenuation coefficient and diffusion attenuation coefficient of the workpiece to be tested to the ultrasonic shear wave are calculated according to the amplitude. The present invention eliminates the influence of diffusion attenuation in the attenuation coefficient measurement through the pre-designed test block, calculates the absorption attenuation coefficient, scattering attenuation coefficient and diffusion attenuation coefficient of the workpiece to be tested to the ultrasonic shear wave in turn, obtains the diffusion attenuation coefficient matching the shape and size of the workpiece to be tested, and improves the accuracy of the ultrasonic shear wave attenuation coefficient measurement.

Optionally, the ultrasonic shear wave probe is equipped with a magnetic attraction or clamping device to ensure that the coupling force of the ultrasonic shear wave probe remains consistent when measuring on different test blocks or workpieces to be tested.

The preset number of test blocks designed by the present invention has the same material properties as the workpiece to be tested, and the test blocks have regular shapes and relatively large sizes, so that the absorption attenuation constant and scattering attenuation constant of the test blocks and the workpiece to be tested can be ensured to be the same, and the diffusion attenuation coefficient conforms to the attenuation formula. By performing ultrasonic shear wave tests on test blocks with different grain sizes, the absorption attenuation constant and scattering attenuation constant of the test blocks can be calculated, thereby obtaining the absorption attenuation coefficient and scattering attenuation coefficient of the workpiece to be tested. In order to be able to solve different attenuation constants, different sets of equations need to be obtained, so it is necessary to perform ultrasonic shear wave measurements on different test blocks and workpieces to be tested. By configuring a magnetic suction or clamping device, it can be ensured that the coupling force of the ultrasonic shear wave probe when fixed on different test blocks or workpieces to be tested is the same, which can make the measured echo amplitude more accurate, thereby further improving the accuracy of the various calculated attenuation coefficients.

Optionally, according to the propagation characteristics of ultrasonic shear waves, an ultrasonic shear wave probe with both ultrasonic transmitting and receiving functions is fixed on the coupling surface of the test block; the ultrasonic shear wave transmitting probe and the ultrasonic shear wave receiving probe are respectively fixed on different positions on the coupling surface of the workpiece to be tested with a preset multiple span apart.

Optionally, if the workpiece to be tested does not have a reflection surface approximately parallel to the coupling surface, a test block with the same sound beam diffusion cross-sectional area as the ultrasonic shear wave probe is manufactured, and the thickness, material and surface roughness of the test block are the same as those of the workpiece to be tested.

If the workpiece to be tested by the present invention does not have a reflecting surface that is approximately parallel to the coupling surface, the conditions for multiple reflections cannot be met. Direct ultrasonic shear wave measurement will affect the formation of the echo, resulting in inaccurate calculation of the attenuation coefficient. Therefore, a test block with the same material properties as the workpiece to be tested can be processed and used to replace the workpiece to be tested for measurement, thereby ensuring the accuracy of the attenuation coefficient measurement.

In a second aspect, an embodiment of the present invention provides a working method of a device for measuring an ultrasonic shear wave attenuation coefficient, comprising the following steps:

Determine the coupling surface and reflection surface of the test block, select the rectangular surface of the semi-cylindrical test block as the coupling surface, and the semi-cylindrical curved surface as the reflection surface, or select the opposite upper surfaces of the isosceles trapezoidal test block as the coupling surface, and the two isosceles trapezoidal surfaces as the reflection surfaces;

An ultrasonic shear wave probe of a preset frequency is fixed to the coupling surfaces of a preset number of test blocks respectively, and an ultrasonic detector is used to excite the ultrasonic shear wave probe to transmit ultrasonic shear waves to the corresponding reflection surface of each test block;

The ultrasonic shear wave forms an echo between the coupling surface and the reflection surface of each test block, the ultrasonic shear wave probe receives a preset number of echoes reflected by each test block from the reflection surface, and the ultrasonic detector records the amplitudes of different echoes, obtains an absorption attenuation constant and a scattering attenuation constant according to the amplitude, and calculates an absorption attenuation coefficient and a scattering attenuation coefficient of the workpiece to be tested according to the absorption attenuation constant and the scattering attenuation constant;

Select two relatively parallel surfaces of the workpiece to be tested as its coupling surface and reflection surface respectively, and fix an ultrasonic shear wave transmitting probe of a preset frequency on the coupling surface of the workpiece to be tested, and use an ultrasonic detector to excite the ultrasonic shear wave transmitting probe to transmit ultrasonic shear waves to the reflection surface of the workpiece to be tested;

The ultrasonic shear wave forms an echo between the coupling surface and the reflecting surface of the workpiece to be measured, and the ultrasonic shear wave receiving probe is fixed at a preset multiple span to receive the echo at the preset multiple span reflected by the reflecting surface. The amplitudes of different echoes are recorded by the ultrasonic detector, and the diffusion attenuation coefficient of the workpiece to be measured is calculated based on the amplitude and the absorption attenuation coefficient and the scattering attenuation coefficient.

The working method of the ultrasonic shear wave attenuation coefficient measuring device provided by the embodiment of the present invention is as follows: a semi-cylindrical test block and an isosceles trapezoidal test block are designed in advance according to the material properties of the workpiece to be measured and the attenuation characteristics of the ultrasonic shear wave as test blocks; an ultrasonic detector excites an ultrasonic shear wave transmitting probe fixed on each test block or the coupling surface of the workpiece to be measured to generate an ultrasonic shear wave of a preset frequency, and transmits the ultrasonic shear wave to the corresponding reflecting surface; the ultrasonic shear wave forms an echo between the coupling surface and the reflecting surface; the ultrasonic shear wave receiving probe receives the reflected echoes a preset number of times and the ultrasonic detector records the amplitude of each echo; the absorption attenuation constant and the scattering attenuation constant of the workpiece to be measured for the ultrasonic shear wave are calculated according to the echo amplitude of the test block, and then the absorption attenuation coefficient and the scattering attenuation coefficient of the workpiece to be measured are calculated; and the diffusion attenuation coefficient of the workpiece to be measured for the ultrasonic shear wave is calculated according to the absorption attenuation coefficient and the scattering attenuation coefficient of the workpiece to be measured and the echo amplitude of the workpiece to be measured. The present invention eliminates the influence of diffusion attenuation in attenuation coefficient measurement through a pre-designed test block, calculates the absorption attenuation coefficient, scattering attenuation coefficient and diffusion attenuation coefficient of the workpiece to be measured in sequence, obtains the diffusion attenuation coefficient matching the shape and size of the workpiece to be measured, and improves the accuracy of ultrasonic shear wave attenuation coefficient measurement.

Optionally, on the test block, the incident point and the receiving point of the ultrasonic shear wave are both the center position of the coupling surface of the test block, the ultrasonic shear wave passes through the axis of the semi-cylindrical test block and is emitted along the radius direction of the cross section of the semi-cylindrical test block, or is emitted parallel to the normal direction of the trapezoidal surface of the isosceles trapezoidal test block; on the workpiece to be tested, the incident point of the ultrasonic shear wave is the fixed position of the ultrasonic shear wave transmitting probe, and the receiving point is the fixed position of the ultrasonic shear wave receiving probe, and the ultrasonic shear wave is emitted toward the reflecting surface of the workpiece to be tested at a preset refraction angle.

The present invention pre-designs test blocks with different average grain sizes, and ultrasonic shear waves form echoes on the coupling surface and reflection surface of the test block. According to the frequency of the ultrasonic shear wave, the preset refraction angle and the chip size, a semi-cylindrical or trapezoidal test block is designed, so that after the ultrasonic shear wave probe is coupled to the upper surface of the test block, the emitted shear wave can be reflected back and forth on the semi-cylindrical surface or on the two waist surfaces of the trapezoidal test block, thereby obtaining the ultrasonic shear wave sound pressure after multiple reflections.

Optionally, the diffusion attenuation coefficients of the semi-cylindrical test block and the isosceles trapezoidal test block satisfy an attenuation formula.

The test block pre-designed in the present invention can make the diffusion attenuation coefficient of the test block satisfy the attenuation formula due to its special shape design or relatively large sound beam propagation cross section, thereby eliminating the influence of diffusion attenuation in attenuation coefficient measurement. The diffusion attenuation coefficient is calculated by the attenuation formula, and its diffusion attenuation coefficient can be used as a known quantity in the process of measuring the ultrasonic shear wave attenuation coefficient, thereby simplifying the calculation process.

Optionally, the number of the semi-cylindrical test blocks or isosceles trapezoidal test blocks is at least 2.

The present invention obtains the absorption attenuation constant and the scattering attenuation constant by testing the test block, which includes two unknown quantities. Therefore, in the process of measuring the ultrasonic shear wave attenuation coefficient, at least one set of two-variable linear equations is generated to ensure that the absorption attenuation constant and the scattering attenuation constant can be calculated. Therefore, in the test process, two semi-cylindrical test blocks or isosceles trapezoidal test blocks are selected. Except for the average grain size, the other material properties of the two test blocks are the same, so that two sets of two-variable linear equations can be generated in the measurement process. A set of two-variable linear equations is generated by combining the equations, which can ensure that the equations have solutions, that is, the absorption attenuation constant and the scattering attenuation constant can be calculated.

Optionally, the ultrasonic shear wave probe receives a preset number of echoes reflected by each test block from a reflecting surface, and records the amplitudes of different echoes by the ultrasonic detector, obtains an absorption attenuation constant and a scattering attenuation constant according to the amplitudes, and calculates an absorption attenuation coefficient and a scattering attenuation coefficient of the workpiece to be tested according to the absorption attenuation constant and the scattering attenuation constant, including: the ultrasonic shear wave forms echoes on the reflecting surface of the first test block and the reflecting surface of the second test block; the ultrasonic shear wave probe receives m echoes and n echoes formed on the reflecting surface of the first test block, and records the first amplitude of the m echoes and the second amplitude of the n echoes by the ultrasonic detector; and calculates the first test block according to the first amplitude and the second amplitude. The first attenuation coefficient of the test block is obtained, and a first equation between the first attenuation coefficient and the absorption attenuation constant and the scattering attenuation constant is constructed; the ultrasonic shear wave probe receives m echoes and n echoes formed on the reflecting surface of the second test block, and records the third amplitude of the m echoes and the fourth amplitude of the n echoes through the ultrasonic detector; the second attenuation coefficient of the second test block is calculated according to the third amplitude and the fourth amplitude, and a second equation between the second attenuation coefficient and the absorption attenuation constant and the scattering attenuation constant is constructed; the first equation and the second equation are combined to calculate the absorption attenuation constant and the scattering attenuation constant; the absorption attenuation coefficient and the scattering attenuation coefficient of the workpiece to be tested are calculated according to the absorption attenuation constant and the scattering attenuation constant.

The present invention uses ultrasonic shear wave measurement with two identical steps, and ultrasonic shear waves of the same frequency form echoes on the coupling surfaces and reflection surfaces of different test blocks. A preset number of echoes is selected, and the attenuation coefficients of the two test blocks can be obtained by the echo amplitude. Among them, the attenuation coefficient is the sum of the absorption attenuation coefficient, the scattering attenuation coefficient and the diffusion attenuation coefficient. There are fixed relationships between the absorption attenuation coefficient and the scattering attenuation coefficient and the corresponding absorption attenuation constant and scattering attenuation constant, respectively, and the diffusion attenuation coefficient can be calculated according to the attenuation formula. Therefore, two sets of relationship formulas between the attenuation coefficient and the absorption attenuation constant and the scattering attenuation constant can be obtained. Two binary linear equations are combined to obtain a set of binary linear equations. Therefore, the two constants can be solved by the binary linear equations, and the absorption attenuation coefficient and the scattering attenuation coefficient of the workpiece to be measured can be calculated by substituting the two constants into the fixed relationship corresponding to the workpiece to be measured.

Optionally, the process of fixing the ultrasonic shear wave receiving probe at a preset multiple span, receiving echoes at a preset multiple span reflected by a reflecting surface, recording the amplitudes of different echoes by the ultrasonic detector, and calculating the diffusion attenuation coefficient of the workpiece to be measured according to the amplitudes and the absorption attenuation coefficient and the scattering attenuation coefficient includes: the ultrasonic shear wave forms an echo on the reflecting surface of the workpiece to be measured, and the ultrasonic shear wave receiving probe is respectively fixed at a first position m times the span and a second position n times the span away from the ultrasonic shear wave transmitting probe in the coupling surface; the ultrasonic shear wave receiving probe receives the m times span echo at the first position and the n times span echo at the second position, and records the fifth amplitude of the m times span echo and the sixth amplitude of the n times span echo by the ultrasonic detector; the third attenuation coefficient of the workpiece to be measured is calculated according to the fifth amplitude and the sixth amplitude; the diffusion attenuation coefficient is calculated according to the third attenuation coefficient, the absorption attenuation coefficient and the scattering attenuation coefficient of the workpiece to be measured.

The present invention applies ultrasonic shear waves of the same frequency to the workpiece to be measured, and the ultrasonic shear waves form echoes on the coupling surface and the reflection surface of the workpiece to be measured, and selects echoes at different preset multiple spans. The total attenuation coefficient of the workpiece to be measured can be obtained through the echo amplitude, and then the absorption attenuation coefficient and the scattering attenuation coefficient that have been solved are subtracted to obtain the diffusion attenuation coefficient of the workpiece to be measured. For workpieces to be measured with different shapes and sizes, since the absorption attenuation and scattering attenuation are independent of the shape and size of the workpiece, but the diffusion attenuation will be affected, the actual workpiece to be measured is used to measure its diffusion attenuation, so that the diffusion attenuation coefficients of the workpieces to be measured with different shapes and sizes can be obtained, thereby improving the accuracy of attenuation coefficient measurement.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a schematic structural diagram of a device for measuring ultrasonic shear wave attenuation coefficient provided by an embodiment of the present invention;

FIG2 is a schematic flow chart of a working method of a device for measuring ultrasonic shear wave attenuation coefficient provided by an embodiment of the present invention;

3 is a schematic diagram of the structure of a semi-cylindrical test block of a device for measuring ultrasonic shear wave attenuation coefficient provided by an embodiment of the present invention;

FIG4 is a schematic diagram of the structure of a workpiece to be measured of a device for measuring ultrasonic shear wave attenuation coefficient provided by an embodiment of the present invention;

FIG5 is a schematic diagram of an isosceles trapezoidal test block structure of a device for measuring ultrasonic shear wave attenuation coefficient provided by an embodiment of the present invention.

DETAILED DESCRIPTION

In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

Example 1

The embodiment of the present invention provides a device for measuring ultrasonic shear wave attenuation coefficient, as shown in FIG1 , the system comprises: an ultrasonic detector, an ultrasonic shear wave probe and a preset number of test blocks;

The ultrasonic detector is used to excite the ultrasonic shear wave transmitting probe to generate ultrasonic shear waves of a preset frequency, and record the echo amplitudes formed by the ultrasonic shear waves received by the ultrasonic shear wave receiving probe on the reflection surfaces of the test block and the workpiece to be tested, and calculate the absorption attenuation coefficient, scattering attenuation coefficient and diffusion attenuation coefficient of the workpiece to be tested in sequence according to the amplitudes;

Specifically, in an embodiment of the present invention, the ultrasonic detector has the function of accurately measuring the amplitude of each echo and has the function of gain compensation. The ultrasonic detector generates and emits ultrasonic shear waves by exciting an ultrasonic shear wave transmitting probe fixed on the coupling surface of the test block or the workpiece to be tested. The emitted ultrasonic shear waves are reflected multiple times between the coupling surface and the reflecting surface of the test block or the workpiece to be tested to form echoes and are received by the ultrasonic shear wave receiving probe. The ultrasonic detector obtains the amplitude of the preset number of echoes or the preset multiple span through the ultrasonic shear wave receiving probe, and calculates the absorption attenuation coefficient, scattering attenuation coefficient and diffusion attenuation coefficient of the workpiece to be tested in turn according to the amplitude.

The ultrasonic shear wave probe includes an ultrasonic shear wave transmitting probe and an ultrasonic shear wave receiving probe, which are used to be fixed on the coupling surface of the test block or the workpiece to be tested. The ultrasonic shear wave transmitting probe is excited by the ultrasonic detector to generate and transmit ultrasonic shear waves, and the ultrasonic shear wave receiving probe receives the echo of the ultrasonic shear wave and returns it to the ultrasonic detector.

Specifically, in an embodiment of the present invention, a magnetic attraction or clamping device is provided around the ultrasonic shear wave probe to ensure that the coupling force of the ultrasonic shear wave probe remains consistent when measuring on different test blocks or workpieces to be tested. In addition, according to the propagation characteristics of ultrasonic shear waves, an ultrasonic shear wave probe with both ultrasonic transmitting and ultrasonic receiving functions is fixed on the coupling surface of the test block; the ultrasonic shear wave transmitting probe and the ultrasonic shear wave receiving probe are respectively fixed on different positions of the coupling surface of the workpiece to be tested separated by a preset multiple span, wherein the preset multiple corresponds to the preset number of echo measurements performed on the test block.

The test block is designed according to the material properties of the workpiece to be tested and the attenuation characteristics of the ultrasonic shear wave, so that the ultrasonic shear wave propagates inside it and forms an echo on the reflection surface, and the echo is used to calculate the absorption attenuation coefficient, scattering attenuation coefficient and diffusion attenuation coefficient of the workpiece to be tested; the test block includes: a preset number of semi-cylindrical test blocks or a preset number of isosceles trapezoidal test blocks, the surface roughness, acoustic impedance and material of the semi-cylindrical test blocks or isosceles trapezoidal test blocks are the same as those of the workpiece to be tested; the cylindrical radius of each of the semi-cylindrical test blocks is the same and is set to be larger than the ultrasonic The preset multiple of the near field zone of the ultrasonic shear wave probe, the surface roughness is set to a first preset ratio less than the wavelength of the shear wave, the average grain size of each of the semi-cylindrical test blocks is different, and is set to a second preset ratio less than the wavelength of the shear wave; the distance between the isosceles trapezoidal surface of each of the isosceles trapezoidal test blocks and the ultrasonic shear wave incident point is the same, and is set to be greater than the preset multiple of the near field zone of the ultrasonic shear wave probe, the surface roughness is set to a first preset ratio less than the wavelength of the shear wave, the average grain size of each of the isosceles trapezoidal test blocks is different, and is set to a second preset ratio less than the wavelength of the shear wave.

Specifically, in the embodiment of the present invention, the test block is designed according to the material properties of the workpiece to be tested and the attenuation characteristics of the ultrasonic shear wave, wherein the ultrasonic shear wave is within about 2 times the near field of the probe, and the attenuation of the ultrasonic shear wave emitted by the probe is mainly composed of absorption attenuation and scattering attenuation. Therefore, the cylindrical radius of each semi-cylindrical test block or the distance between the isosceles trapezoidal surface of the isosceles trapezoidal test block and the ultrasonic shear wave incident point are set to be greater than 3 times the near field of the ultrasonic shear wave probe, but not limited to this. In addition, the surface roughness is set to be less than 1/3 of the shear wave wavelength, and the average grain size is different, but is set to be less than 1/10 of the shear wave wavelength, but not limited to this.

In the embodiment of the present invention, not every workpiece to be tested can find two mutually parallel coupling surfaces and reflection surfaces, thus forming the conditions for multiple reflections. If the workpiece to be tested does not have a reflection surface approximately parallel to the coupling surface, a test block with the same cross-sectional area as the sound beam diffusion of the ultrasonic shear wave probe is processed and manufactured, and the thickness, material and surface roughness of the test block are the same as those of the workpiece to be tested, and the test block is used instead of the workpiece to measure the attenuation coefficient.

The ultrasonic shear wave attenuation coefficient measuring device provided by the embodiment of the present invention is designed in advance according to the material properties of the workpiece to be tested and the attenuation characteristics of the ultrasonic shear wave. A semi-cylindrical test block and an isosceles trapezoidal test block are used as test blocks. The ultrasonic shear wave probe fixed on each test block or the coupling surface of the workpiece to be tested is excited by an ultrasonic detector to generate an ultrasonic shear wave of a preset frequency, and the ultrasonic shear wave is emitted to the corresponding reflection surface. The ultrasonic shear wave forms an echo between the coupling surface and the reflection surface. The ultrasonic shear wave probe receives the preset number of reflected echoes and the ultrasonic detector records the amplitude of each echo. The absorption attenuation coefficient, scattering attenuation coefficient and diffusion attenuation coefficient of the workpiece to be tested to the ultrasonic shear wave are calculated according to the amplitude. The present invention eliminates the influence of diffusion attenuation in the attenuation coefficient measurement through the pre-designed test block, calculates the absorption attenuation coefficient, scattering attenuation coefficient and diffusion attenuation coefficient of the workpiece to be tested in turn, obtains the diffusion attenuation coefficient matching the shape and size of the workpiece to be tested, and improves the accuracy of the ultrasonic shear wave attenuation coefficient measurement.

Example 2

The embodiment of the present invention provides a working method of a device for measuring ultrasonic shear wave attenuation coefficient. As shown in FIG2 , the method measures the attenuation coefficient based on the device provided in Example 1. The test block takes a semi-cylindrical test block as an example. The steps include:

Step S1: Determine the coupling surface and reflection surface of the test block, select the rectangular surface of the semi-cylindrical test block as the coupling surface, and the semi-cylindrical curved surface as the reflection surface, or select the upper surface of the isosceles trapezoidal test block as the coupling surface, and the two isosceles trapezoidal surfaces as the reflection surfaces;

Specifically, in the embodiment of the present invention, the semi-cylindrical test block is designed in advance according to the material properties of the workpiece to be tested and the attenuation characteristics of the ultrasonic shear wave, and the semi-cylindrical test block is designed according to the frequency of the ultrasonic shear wave, the preset refraction angle and the chip size, so that after the ultrasonic shear wave probe is coupled to the rectangular surface of the semi-cylindrical test block, the emitted shear wave can be reciprocated and reflected on the semi-cylindrical surface. Therefore, by determining the coupling surface and the reflection surface of the semi-cylindrical test block, the fixed position of the ultrasonic shear wave probe is determined.

Step S2: fixing ultrasonic shear wave probes of preset frequencies on coupling surfaces of a preset number of test blocks respectively, and using an ultrasonic detector to excite the ultrasonic shear wave probes to emit ultrasonic shear waves to the corresponding reflection surfaces of each test block.

Specifically, in the embodiment of the present invention, the absorption attenuation constant and the scattering attenuation constant are calculated according to the echo amplitude formed in the test block, which contains two unknown quantities. In the process of measuring the ultrasonic shear wave attenuation coefficient, at least one set of two-variable linear equations is generated to ensure that the absorption attenuation constant and the scattering attenuation constant can be calculated. Therefore, the number of semi-cylindrical test blocks is set to 2, but it is not limited to this. In actual applications, it can be other multiple numbers. At least two are set to perform subsequent attenuation constant calculation. The average grain sizes of the two semi-cylindrical test blocks are _d1 and _d2 respectively, and the cylindrical surface radius is R. In the embodiment of the present invention, as shown in FIG3, an ultrasonic shear wave probe with a frequency of f is fixed at the center of the coupling surface of a semi-cylindrical test block 1 with an average grain size of _d1 and a cylindrical surface radius of R, so that the probe incident point coincides with the center of the upper surface, and an ultrasonic detector is used to excite the ultrasonic shear wave probe to generate and emit ultrasonic shear waves, and the ultrasonic shear waves pass through the axis of the semi-cylindrical test block and are emitted along the radius direction of the cross section of the semi-cylindrical test block.

Step S3: The ultrasonic shear wave forms an echo between the coupling surface and the reflecting surface of each test block, and the ultrasonic shear wave probe receives a preset number of echoes reflected by each test block from the reflecting surface, and the amplitudes of different echoes are recorded by the ultrasonic detector, and the absorption attenuation constant and the scattering attenuation constant are obtained according to the amplitude, and the absorption attenuation coefficient and the scattering attenuation coefficient of the workpiece to be tested are calculated according to the absorption attenuation constant and the scattering attenuation constant.

Specifically, in the embodiment of the present invention, the ultrasonic shear wave probe receives the m-th echo and the n-th echo formed on the reflecting surface of the semi-cylindrical test block 1, and records the first amplitude A _m of the m-th echo and the second amplitude A _n (n>m) of the n-th echo of the ultrasonic shear wave on the semi-cylindrical surface through the ultrasonic detector. According to the relationship between the attenuation coefficient and the echo amplitude, the first attenuation coefficient α ₁ of the semi-cylindrical test block 1 is calculated. At the same time, an equation between the first attenuation coefficient and the absorption attenuation constant _Ca and the scattering attenuation constant C _s is constructed, wherein the attenuation coefficient is the sum of the absorption attenuation coefficient, the scattering attenuation coefficient and the diffusion attenuation coefficient. Since the semi-cylindrical test block has a regular shape and a large size, its diffusion attenuation coefficient α _d satisfies the attenuation formula, as described below:

Therefore, the attenuation coefficient of the semi-cylindrical test block 1 is: α ₁ =α _a +α _s1 + _d , and the obtained equation is as follows:

Wherein, _α1 is the first attenuation coefficient of ultrasonic shear wave on the semi-cylindrical test block 1, _αa is the absorption attenuation coefficient, _αs1 is the scattering attenuation coefficient of the semi-cylindrical test block 1, _Ca is the absorption attenuation constant, _Cs is the scattering attenuation constant, f is the ultrasonic shear wave frequency, _d1 is the average grain size of the semi-cylindrical test block 1, R is the cylindrical surface radius of the semi-cylindrical test block 1, and δ is the single bottom wave reflection loss of the semi-cylindrical test block 1.

Repeat steps S2 and S3, fix the ultrasonic shear wave probe with a frequency of f at the center of the coupling surface of the semi-cylindrical test block 2 with an average grain size of d ₂ and a cylindrical radius of R, and use an ultrasonic detector to excite the ultrasonic shear wave probe to generate and emit ultrasonic shear waves. The ultrasonic shear wave forms echoes on the coupling surface and the reflection surface of the semi-cylindrical test block 2. The ultrasonic shear wave probe receives the m-th echo and the n-th echo formed on the reflection surface of the semi-cylindrical test block 2, and records the third amplitude B of the m-th echo of the ultrasonic shear wave on the semi-cylindrical surface _and the fourth amplitude B _m (n＞m) of the m-th echo through the ultrasonic detector. According to the relationship between the attenuation coefficient and the echo amplitude, the second attenuation coefficient α ₂ of the semi-cylindrical test block 2 is calculated, and at the same time, the equation between the second attenuation coefficient and the absorption attenuation constant _Ca and the scattering attenuation constant _Cs is constructed, as shown below:

Wherein, _α2 is the second attenuation coefficient of the ultrasonic shear wave on the semi-cylindrical test block 2, _αa is the absorption attenuation coefficient, _αs2 is the scattering attenuation coefficient of the semi-cylindrical test block 2, _Ca is the absorption attenuation constant, _Cs is the scattering attenuation constant, f is the ultrasonic shear wave frequency, _d2 is the average grain size of the semi-cylindrical test block 2, R is the cylindrical surface radius of the semi-cylindrical test block 2, and δ is the single bottom wave reflection loss of the semi-cylindrical test block 2.

Combining equation (2) with equation (3), we can obtain the absorption attenuation constant _Ca and the scattering attenuation constant _Cs :

According to the fixed relationship of _αa = _af and _αs ⁼ _sf4d3 , ^the absorption attenuation coefficient and scattering attenuation coefficient of the workpiece to be measured are calculated:

Where d _c is the average grain size of the workpiece to be tested.

Step S4: select two relatively parallel surfaces of the workpiece to be tested as its coupling surface and reflection surface respectively, and fix an ultrasonic shear wave transmitting probe of a preset frequency on the coupling surface of the workpiece to be tested, and use an ultrasonic detector to excite the ultrasonic shear wave transmitting probe to transmit ultrasonic shear waves to the reflection surface of the workpiece to be tested.

Specifically, in an embodiment of the present invention, two relatively parallel surfaces of the workpiece to be tested are selected as coupling surfaces and reflection surfaces. If the workpiece to be tested does not have a reflection surface approximately parallel to the coupling surface, a test workpiece with a regular shape having the same material properties as the workpiece to be tested is designed. An ultrasonic shear wave transmitting probe with a frequency of f is fixed at a certain position on the coupling surface of the workpiece to be tested or the test workpiece, and an ultrasonic shear wave receiving probe is fixed at a position where the spacing between the ultrasonic shear wave transmitting probe and the ultrasonic shear wave receiving probe is a preset multiple span. As shown in FIG4 , the ultrasonic shear wave receiving probe is fixed at a position where the spacing between the ultrasonic shear wave transmitting probe and the ultrasonic shear wave transmitting probe is a single span, which is only used as an example and is not limited thereto. An ultrasonic detector is used to excite the ultrasonic shear wave transmitting probe to generate ultrasonic shear waves, and the shear waves are emitted according to a preset refraction angle β.

Step S5: The ultrasonic shear wave forms an echo between the coupling surface and the reflecting surface of the workpiece to be measured, and the ultrasonic shear wave receiving probe is fixed at a preset multiple span to receive the echo at the preset multiple span reflected by the reflecting surface, and the amplitudes of different echoes are recorded by the ultrasonic detector, and the diffusion attenuation coefficient of the workpiece to be measured is calculated based on the amplitude and the absorption attenuation coefficient and the scattering attenuation coefficient.

Specifically, in the embodiment of the present invention, the ultrasonic shear wave forms an echo on the coupling surface and the reflection surface of the workpiece to be measured. The ultrasonic shear wave receiving probe is fixed at a first position m times the span and a second position n times the span away from the ultrasonic shear wave transmitting probe in the coupling surface. The ultrasonic shear wave receiving probe receives the m times span echo of the first position and the n times span echo of the second position respectively, and records the fifth amplitude C _m of the m times span echo of the ultrasonic shear wave on the reflection surface and the sixth amplitude C _n (n>m) of the n times span echo through the ultrasonic detector. The third attenuation coefficient α ₃ of the workpiece to be measured is calculated according to the echo amplitude, and the diffusion attenuation coefficient is calculated according to the absorption attenuation coefficient and the scattering attenuation coefficient of the workpiece to be measured. The calculation formula is as follows:

α _dc =α ₃ -α _ac -α _sc (9)

Wherein, H is the thickness of the workpiece to be measured, β is the preset refraction angle of the ultrasonic shear wave transmitting probe, and δ _c is the single bottom wave reflection loss of the workpiece to be measured.

The working method of the ultrasonic shear wave attenuation coefficient measuring device provided by the embodiment of the present invention is as follows: a semi-cylindrical test block and an isosceles trapezoidal test block are designed in advance according to the material properties of the workpiece to be measured and the attenuation characteristics of the ultrasonic shear wave as test blocks; an ultrasonic detector excites an ultrasonic shear wave transmitting probe fixed on each test block or the coupling surface of the workpiece to be measured to generate an ultrasonic shear wave of a preset frequency, and transmits the ultrasonic shear wave to the corresponding reflection surface; the ultrasonic shear wave forms an echo between the coupling surface and the reflection surface; the ultrasonic shear wave receiving probe receives the reflected echoes a preset number of times and the ultrasonic detector records the amplitude of each echo; the absorption attenuation constant and scattering attenuation constant of the workpiece to be measured for the ultrasonic shear wave are obtained according to the echo amplitude of the test block, and then the absorption attenuation coefficient and scattering attenuation coefficient of the workpiece to be measured are calculated; and the diffusion attenuation coefficient of the workpiece to be measured for the ultrasonic shear wave is calculated according to the absorption attenuation coefficient and scattering attenuation coefficient of the workpiece to be measured and the echo amplitude of the workpiece to be measured. The present invention eliminates the influence of diffusion attenuation in attenuation coefficient measurement through a pre-designed test block, calculates the absorption attenuation coefficient, scattering attenuation coefficient and diffusion attenuation coefficient of the workpiece to be measured in sequence, obtains the diffusion attenuation coefficient matching the shape and size of the workpiece to be measured, and improves the accuracy of ultrasonic shear wave attenuation coefficient measurement.

Example 3

The embodiment of the present invention provides a working method of a device for measuring an ultrasonic shear wave attenuation coefficient. The method measures the attenuation coefficient based on the device provided in Example 1. The test block takes an isosceles trapezoidal test block as an example. The steps include:

Step S1: Determine the coupling surface and reflection surface of the test block, select the rectangular surface of the semi-cylindrical test block as the coupling surface, and the semi-cylindrical curved surface as the reflection surface, or select the upper surface of the isosceles trapezoidal test block as the coupling surface, and the two isosceles trapezoidal surfaces as the reflection surfaces;

Specifically, in the embodiment of the present invention, an isosceles trapezoidal test block is designed in advance according to the material properties of the workpiece to be tested and the attenuation characteristics of the ultrasonic shear wave, and the isosceles trapezoidal test block is designed according to the frequency of the ultrasonic shear wave, the preset refraction angle and the chip size, so that after the ultrasonic shear wave probe is coupled to the upper surface of the isosceles trapezoidal test block, the emitted shear wave can be reciprocated and reflected on the two waist surfaces of the trapezoidal test block. Therefore, by determining the coupling surface and the reflection surface of the isosceles trapezoidal test block, the fixed position of the ultrasonic shear wave probe is determined.

Step S2: fixing ultrasonic shear wave probes of preset frequencies on coupling surfaces of a preset number of test blocks respectively, and using an ultrasonic detector to excite the ultrasonic shear wave probes to emit ultrasonic shear waves to the corresponding reflection surfaces of each test block.

Specifically, in the embodiment of the present invention, the number of isosceles trapezoidal test blocks is set to 2, but is not limited thereto. The average grain sizes of the two isosceles trapezoidal test blocks are _d1 and _d2 , respectively, and the distances between the isosceles trapezoidal surfaces and the ultrasonic incident point are both h. In the embodiment of the present invention, as shown in FIG5 , an ultrasonic shear wave probe with a frequency of f is fixed at the center of the coupling surface of an isosceles trapezoidal test block 1 with an average grain size of _d1 and a distance between the isosceles trapezoidal surface and the ultrasonic incident point of h, and an ultrasonic detector is used to excite the ultrasonic shear wave probe to generate and emit ultrasonic shear waves, and the ultrasonic shear waves are emitted to the two isosceles trapezoidal surfaces in parallel with the normal direction of the trapezoidal surface of the isosceles trapezoidal test block.

Step S3: The ultrasonic shear wave forms an echo between the coupling surface and the reflecting surface of each test block, and the ultrasonic shear wave probe receives a preset number of echoes reflected by each test block from the reflecting surface, and the amplitudes of different echoes are recorded by the ultrasonic detector, and the absorption attenuation constant and the scattering attenuation constant are obtained according to the amplitude, and the absorption attenuation coefficient and the scattering attenuation coefficient of the workpiece to be tested are calculated according to the absorption attenuation constant and the scattering attenuation constant.

Specifically, in the embodiment of the present invention, the ultrasonic shear wave probe receives the m-th echo and the n-th echo formed on the reflection surface of the isosceles trapezoidal test block 1, and records the first amplitude A _m of the m-th echo and the second amplitude A _n (n>m) of the n-th echo of the ultrasonic shear wave on the reflection surface through the ultrasonic detector. According to the relationship between the attenuation coefficient and the echo amplitude, the first attenuation coefficient α ₁ of the isosceles trapezoidal test block 1 is calculated. At the same time, the first equation between the first attenuation coefficient and the absorption attenuation constant _Ca and the scattering attenuation constant C _s is constructed, wherein the attenuation coefficient is the sum of the absorption attenuation coefficient, the scattering attenuation coefficient and the diffusion attenuation coefficient. Since the isosceles trapezoidal test block has a regular shape and a large size, its diffusion attenuation coefficient α _d conforms to the attenuation formula, as shown below:

Therefore, the attenuation coefficient of the isosceles trapezoidal test block 1 is: α ₁ =α _a +α _s1 +α _d , and the obtained equation is as follows:

Wherein, _α1 is the first attenuation coefficient of ultrasonic shear wave on the isosceles trapezoidal specimen 1, _αa is the absorption attenuation coefficient, _αs1 is the scattering attenuation coefficient of the isosceles trapezoidal specimen 1, _Ca is the absorption attenuation constant, _Cs is the scattering attenuation constant, f is the ultrasonic shear wave frequency, _d1 is the average grain size of the isosceles trapezoidal specimen 1, h is the distance between the isosceles trapezoidal surface of the isosceles trapezoidal specimen 1 and the ultrasonic incident point, and δ is the single bottom wave reflection loss of the isosceles trapezoidal specimen 1.

Repeat steps S2 and S3, fix the ultrasonic shear wave probe with a frequency of f at the center of the coupling surface of the isosceles trapezoidal test block 2 with an average grain size of d ₂ and a distance of h between the isosceles trapezoidal surface and the ultrasonic incident point, and use an ultrasonic detector to excite the ultrasonic shear wave probe to generate and emit ultrasonic shear waves. The ultrasonic shear wave forms echoes on the coupling surface and the reflection surface of the isosceles trapezoidal test block 2. The ultrasonic shear wave probe receives the m-th echo and the n-th echo formed on the reflection surface of the isosceles trapezoidal test block 2, and records the third amplitude B _m of the m-th echo and the fourth amplitude B _n (n＞m) of the n-th echo of the ultrasonic shear wave on the reflection surface through the ultrasonic detector. According to the relationship between the attenuation coefficient and the echo amplitude, calculate the second attenuation coefficient α ₂ of the isosceles trapezoidal test block 2. At the same time, construct equations between the second attenuation coefficient and the absorption attenuation constant _Ca and the scattering attenuation constant _Cs , as shown below:

Wherein, _α2 is the second attenuation coefficient of ultrasonic shear wave on the isosceles trapezoidal specimen 2, _αa is the absorption attenuation coefficient, _αs2 is the scattering attenuation coefficient of the isosceles trapezoidal specimen 2, _Ca is the absorption attenuation constant, _Cs is the scattering attenuation constant, f is the ultrasonic shear wave frequency, _d2 is the average grain size of the isosceles trapezoidal specimen 2, h is the distance between the isosceles trapezoidal surface of the isosceles trapezoidal specimen 2 and the ultrasonic incident point, and δ is the single bottom wave reflection loss of the isosceles trapezoidal specimen 2.

Combining the above equation (11) with equation (12), we can obtain the absorption attenuation constant and the scattering attenuation constant:

According to α _a =C _a f and α _s =C _s f ⁴ d ³ , the absorption attenuation coefficient and scattering attenuation coefficient of the workpiece to be measured are calculated:

Where d _c is the average grain size of the workpiece to be tested.

Step S4: select two relatively parallel surfaces of the workpiece to be tested as its coupling surface and reflection surface respectively, and fix an ultrasonic shear wave transmitting probe of a preset frequency on the coupling surface of the workpiece to be tested, and use an ultrasonic detector to excite the ultrasonic shear wave transmitting probe to transmit ultrasonic shear waves to the reflection surface of the workpiece to be tested.

Specifically, in an embodiment of the present invention, an ultrasonic shear wave transmitting probe with a frequency of f is fixed at a certain position of the coupling surface of the workpiece to be tested, and an ultrasonic detector is used to excite the ultrasonic shear wave transmitting probe to generate ultrasonic shear waves, which are emitted according to a preset refraction angle β.

Step S5: The ultrasonic shear wave forms an echo between the coupling surface and the reflecting surface of the workpiece to be measured, and the ultrasonic shear wave receiving probe is fixed at a preset multiple span to receive the echo at the preset multiple span reflected by the reflecting surface, and the amplitudes of different echoes are recorded by the ultrasonic detector, and the diffusion attenuation coefficient of the workpiece to be measured is calculated based on the amplitude and the absorption attenuation coefficient and the scattering attenuation coefficient.

Specifically, in the embodiment of the present invention, the ultrasonic shear wave forms an echo on the coupling surface and the reflection surface of the workpiece to be measured. The ultrasonic shear wave receiving probe is fixed at a first position m times the span and a second position n times the span away from the ultrasonic shear wave transmitting probe in the coupling surface. The ultrasonic shear wave receiving probe receives the m times span echo of the first position and the n times span echo of the second position respectively, and records the fifth amplitude C _m of the m times span echo of the ultrasonic shear wave on the reflection surface and the sixth amplitude C _n (n>m) of the n times span echo through the ultrasonic detector. The third attenuation coefficient α ₃ of the workpiece to be measured is calculated according to the echo amplitude, and the diffusion attenuation coefficient is calculated according to the absorption attenuation coefficient and the scattering attenuation coefficient of the workpiece to be measured. The calculation formula is as follows:

α _dc =α ₃ -α _ac -α _sc (18)

Wherein, H is the thickness of the workpiece to be measured, β is the preset refraction angle of the ultrasonic shear wave transmitting probe, and δ _c is the single bottom wave reflection loss of the workpiece to be measured.

Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims (10)

1. A device for measuring the attenuation coefficient of ultrasonic transverse waves, comprising: an ultrasonic detector, an ultrasonic transverse wave probe and a preset number of test blocks;

the ultrasonic detector is used for exciting the ultrasonic transverse wave transmitting probe to generate ultrasonic transverse waves with preset frequency, recording echo amplitude formed by the ultrasonic transverse waves received by the ultrasonic transverse wave receiving probe on the reflecting surfaces of the test block and the workpiece to be tested, and sequentially calculating the absorption attenuation coefficient, the scattering attenuation coefficient and the diffusion attenuation coefficient of the workpiece to be tested according to the amplitude;

the ultrasonic transverse wave probe comprises an ultrasonic transverse wave transmitting probe and an ultrasonic transverse wave receiving probe, and is used for being fixed on the coupling surface of the test block or the workpiece to be tested, the ultrasonic transverse wave transmitting probe is excited by the ultrasonic detector to generate ultrasonic transverse waves and transmit the ultrasonic transverse waves, and the ultrasonic transverse wave receiving probe receives echoes of the ultrasonic transverse waves and returns the echoes to the ultrasonic detector;

the test block is designed according to the material property of the workpiece to be tested and the attenuation characteristic of the ultrasonic transverse wave, so that the ultrasonic transverse wave propagates in the ultrasonic test block and forms an echo on the reflecting surface, and the echo is used for calculating the absorption attenuation coefficient, the scattering attenuation coefficient and the diffusion attenuation coefficient of the workpiece to be tested;

The test block comprises: the surface roughness, acoustic impedance and materials of the semi-cylindrical test blocks or the isosceles trapezoid test blocks are the same as those of the workpiece to be tested;

the cylindrical surface radius of each semi-cylindrical test block is the same and is set to be larger than the preset multiple of the near field region of the ultrasonic transverse wave probe, the surface roughness is set to be smaller than the first preset proportion of the transverse wave wavelength, and the average grain sizes of the semi-cylindrical test blocks are different from each other and are set to be smaller than the second preset proportion of the transverse wave wavelength;

the distances between the isosceles trapezoid surfaces of the isosceles trapezoid test blocks and the ultrasonic transverse wave incidence point are the same, the distances are set to be larger than the preset multiple of the near field region of the ultrasonic transverse wave probe, the surface roughness is set to be smaller than the first preset proportion of the transverse wave wavelength, the average grain sizes of the isosceles trapezoid test blocks are different from each other, and the average grain sizes of the isosceles trapezoid test blocks are set to be smaller than the second preset proportion of the transverse wave wavelength.

2. The ultrasonic transverse wave attenuation coefficient measuring device according to claim 1, wherein the ultrasonic transverse wave probe is provided with a magnetic attraction or compression device for ensuring that the coupling force of the ultrasonic transverse wave probe is consistent when measured on different test blocks or workpieces to be measured.

3. The device for measuring attenuation coefficient of ultrasonic transverse wave according to claim 2, wherein,

according to the propagation characteristics of the ultrasonic transverse waves, an ultrasonic transverse wave probe with ultrasonic transmitting and receiving functions is fixed on the coupling surface of the test block;

and respectively fixing an ultrasonic transverse wave transmitting probe and an ultrasonic transverse wave receiving probe at different positions on the coupling surface of the workpiece to be detected, wherein the positions are separated by a preset multiple span.

4. The ultrasonic transverse wave attenuation coefficient measuring device according to claim 1, wherein if the workpiece to be measured does not have a reflecting surface approximately parallel to the coupling surface, a block to be measured having the same acoustic beam diffusion cross-sectional area as the ultrasonic transverse wave probe is manufactured, and the thickness, the material and the surface roughness of the block to be measured are the same as those of the workpiece to be measured.

5. A method of operating a device for measuring the attenuation coefficient of ultrasonic transverse waves, characterized in that the device according to claims 1-4 is used for measuring the attenuation coefficient of ultrasonic transverse waves, the method comprising:

determining a coupling surface and a reflecting surface of a test block, selecting a rectangular surface of a semi-cylindrical test block as the coupling surface, and selecting a semi-cylindrical curved surface as the reflecting surface, or selecting the upper surface of an isosceles trapezoid test block as the coupling surface and two isosceles trapezoid surfaces as the reflecting surfaces;

Respectively fixing ultrasonic transverse wave probes with preset frequency on the coupling surfaces of a preset number of test blocks, and exciting the ultrasonic transverse wave probes to emit ultrasonic transverse waves to the reflecting surfaces corresponding to the test blocks by adopting an ultrasonic detector;

the ultrasonic transverse wave forms echoes between the coupling surface and the reflecting surface of each test block, the ultrasonic transverse wave probe receives echoes of preset times reflected by the reflecting surface of each test block, the ultrasonic detector records the amplitudes of different echoes, the absorption attenuation constant and the scattering attenuation constant are obtained according to the amplitudes, and the absorption attenuation coefficient and the scattering attenuation coefficient of a workpiece to be tested are calculated according to the absorption attenuation constant and the scattering attenuation constant;

selecting two relatively parallel surfaces of a workpiece to be detected as a coupling surface and a reflecting surface respectively, fixing an ultrasonic transverse wave transmitting probe with preset frequency on the coupling surface of the workpiece to be detected, and exciting the ultrasonic transverse wave transmitting probe to transmit ultrasonic transverse waves to the reflecting surface of the workpiece to be detected by adopting an ultrasonic detector;

and the ultrasonic transverse wave forms echo between the coupling surface and the reflecting surface of the workpiece to be detected, the ultrasonic transverse wave receiving probe is fixed at the span position with preset times, the echo at the span position with preset times reflected by the reflecting surface is received, the amplitude of different echoes is recorded by the ultrasonic detector, and the diffusion attenuation coefficient of the workpiece to be detected is calculated according to the amplitude, the absorption attenuation coefficient and the scattering attenuation coefficient.

6. The method of operating an ultrasonic transverse wave attenuation coefficient measuring apparatus according to claim 5, wherein,

on a test block, the incidence point and the receiving point of the ultrasonic transverse wave are the central positions of the coupling surface of the test block, and the ultrasonic transverse wave passes through the axis of the semi-cylindrical test block and is emitted along the radial direction of the cross section of the semi-cylindrical test block or is emitted in parallel with the normal direction of the trapezoid surface of the isosceles trapezoid test block;

on a workpiece to be measured, the incidence point of the ultrasonic transverse wave is the fixed position of the ultrasonic transverse wave transmitting probe, the receiving point is the fixed position of the ultrasonic transverse wave receiving probe, and the ultrasonic transverse wave is transmitted to the reflecting surface of the workpiece to be measured according to a preset refraction angle.

7. The method according to claim 5, wherein the diffusion attenuation coefficients of the semi-cylindrical test block and the isosceles trapezoid test block satisfy the attenuation formula.

8. The method for operating an ultrasonic transverse wave attenuation coefficient measuring device according to claim 5, wherein the number of the semi-cylindrical test blocks or the isosceles trapezoid test blocks is at least 2.

9. The method according to claim 8, wherein the process of receiving, by the ultrasonic transverse wave probe, echoes of the preset times reflected by the reflecting surface from each test block, recording the amplitudes of the different echoes by the ultrasonic detector, obtaining an absorption attenuation constant and a scattering attenuation constant according to the amplitudes, and calculating the absorption attenuation coefficient and the scattering attenuation coefficient of the workpiece to be measured according to the absorption attenuation constant and the scattering attenuation constant comprises:

The ultrasonic transverse wave forms an echo on the reflecting surface of the first test block and the reflecting surface of the second test block;

the ultrasonic transverse wave probe receives m echoes and n echoes formed on the reflecting surface of the first test block, and records a first amplitude of the m echoes and a second amplitude of the n echoes through the ultrasonic detector;

calculating a first attenuation coefficient of a first test block according to the first amplitude and the second amplitude, and constructing a first equation between the first attenuation coefficient and an absorption attenuation constant and a scattering attenuation constant;

the ultrasonic transverse wave probe receives m echoes and n echoes formed on the reflecting surface of the second test block, and records a third amplitude of the m echoes and a fourth amplitude of the n echoes through the ultrasonic detector;

calculating a second attenuation coefficient of a second test block according to the third amplitude and the fourth amplitude, and constructing a second equation between the second attenuation coefficient and the absorption attenuation constant and between the second attenuation coefficient and the scattering attenuation constant;

the absorption attenuation constant and the scattering attenuation constant are calculated by combining the first equation and the second equation;

and calculating the absorption attenuation coefficient and the scattering attenuation coefficient of the workpiece to be measured according to the absorption attenuation constant and the scattering attenuation constant.

10. The method according to claim 9, wherein the step of fixing the ultrasonic transverse wave receiving probe at a preset multiple span, receiving echoes at the preset multiple span reflected by the reflecting surface, recording the amplitudes of the different echoes by the ultrasonic detector, and calculating the diffusion attenuation coefficient of the workpiece to be measured according to the amplitudes, the absorption attenuation coefficient and the scattering attenuation coefficient comprises:

the ultrasonic transverse wave forms an echo on a reflecting surface of a workpiece to be detected, and an ultrasonic transverse wave receiving probe is respectively fixed at a first position which is m times of a span and a second position which is n times of a span in a coupling surface and is away from the ultrasonic transverse wave transmitting probe;

the ultrasonic transverse wave receiving probe receives m times of span echo of the first position and n times of span echo of the second position respectively, and records a fifth amplitude of the m times of span echo and a sixth amplitude of the n times of span echo through an ultrasonic detector;

calculating a third attenuation coefficient of the workpiece to be measured according to the fifth amplitude and the sixth amplitude;

and calculating a diffusion attenuation coefficient according to the third attenuation coefficient, the absorption attenuation coefficient and the scattering attenuation coefficient of the workpiece to be measured.