Contact type dry coupling ultrasonic transverse wave probe

Abstract

The invention provides a contact type dry coupling ultrasonic transverse wave probe, which comprises a dry coupling head and an ultrasonic excitation element, and is characterized in that the dry coupling head is a hemisphere and is used for coupling an ultrasonic transverse wave normal probe and an object to be detected in a dry coupling and point contact manner; and an ultrasonic signal is conducted between the ultrasonic excitation element and the to-be-tested material. The ultrasonic excitation element is attached to the dry coupling head and is used for transmitting and receiving ultrasonic waves. According to the ultrasonic transverse wave probe, the point contact dry coupling of the object to be tested is realized through the dry coupling head, and the ultrasonic transverse wave probe can still be used under the conditions that the object to be tested cannot be processed or a coupling agent is not suitable for being used in the testing process.

Description

Technical Field

[0001] The invention relates to the field of ultrasonic nondestructive testing, and in particular to a contact-type dry-coupled ultrasonic shear wave probe. Background Art

[0002] In the field of ultrasonic nondestructive testing, ultrasonic shear wave probes are core components that transmit ultrasonic pulses and receive echoes. In order to achieve effective acoustic coupling between the probe and the surface of the object to be tested, traditional ultrasonic shear wave probes require the surface of the object to be tested to be flat and use shear wave probe coupling agent. Therefore, when the object to be tested cannot be processed or the coupling agent is not suitable during the test, traditional ultrasonic shear wave probes cannot meet the testing needs. Summary of the invention

[0003] In order to solve the above problems, the present invention provides a contact-type dry-coupled ultrasonic shear wave probe, which includes a dry-coupled head and an ultrasonic excitation element, wherein:

[0004] The dry coupling head is a hemispherical body, and is used to couple the ultrasonic shear wave straight probe and the object to be tested by dry coupling and point contact, and to conduct ultrasonic signals between the ultrasonic excitation element and the material to be tested.

[0005] The ultrasonic excitation element is attached to the dry coupling head to realize the emission and reception of ultrasonic waves.

[0006] When emitting ultrasonic waves, the ultrasonic excitation element vibrates under the stimulation of electric pulses and radiates ultrasonic waves; when receiving ultrasonic waves, when the ultrasonic waves act on the ultrasonic excitation element, the ultrasonic excitation element is forced to vibrate, deform, and convert into corresponding electrical signals.

[0007] In some embodiments, the ultrasonic shear wave probe further includes a liquid backing layer and a shell, wherein:

[0008] The liquid backing layer wraps the ultrasonic excitation element and is used to absorb the ultrasonic waves emitted by the ultrasonic excitation element to prevent excessive interference of clutter on the signal acquisition of the piezoelectric ultrasonic shear wave straight probe; and produces a damping effect to stop the ultrasonic shear wave probe from vibrating as soon as possible after emitting an ultrasonic pulse.

[0009] The housing encapsulates the liquid backing layer and the ultrasonic excitation element, and fixes the dry coupling head on the outside.

[0010] In some more specific embodiments, the ultrasonic shear wave probe further includes a connecting rod, wherein:

[0011] The two ends of the housing are respectively connected to the dry coupling head and the connecting rod, and are also used to transmit the pressure provided by the connecting rod to the dry coupling head.

[0012] The connecting rod is used to apply pressure to the ultrasonic shear wave probe to enhance the coupling between the dry coupling head and the object to be measured.

[0013] In some embodiments, the ultrasonic excitation element is a piezoelectric vibrator.

[0014] In some more specific embodiments, the piezoelectric vibrator is composed of two identical piezoelectric chips bonded in parallel.

[0015] The ultrasonic shear wave probe also includes a negative electrode lead and a positive electrode lead, which are used to conduct electrical signals between the ultrasonic shear wave probe and an external control terminal.

[0016] The positive electrode lead is led out from the bonding surfaces of the two wafers, and the negative electrode lead is connected to the surfaces of the two wafers opposite to the bonding surfaces and led out.

[0017] In some embodiments, the ultrasonic excitation element is a magnetostrictive vibrator.

[0018] In some more specific embodiments, the magnetostrictive vibrator is composed of two magnetostrictive material rods placed in parallel, and the two magnetostrictive material rods are fixed on a dry coupling head.

[0019] The ultrasonic shear wave probe provided by the present invention realizes dry point contact coupling of the object to be tested through a dry coupling head. It can still be used in situations where the object to be tested cannot be processed or the coupling agent is not suitable for use during the test. For general objects to be tested, the process of grinding the surface of the object to be tested can also be omitted. In addition, the sound field distribution of the shear wave emitted by the ultrasonic shear wave probe provided by the present invention is similar to that of a point sound source, has omnidirectionality, and can meet the detection needs inside larger objects to be tested. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 A schematic diagram of the structure of a contact-type dry-coupled ultrasonic shear wave probe provided by the present invention;

[0022] Figure 2 A schematic diagram of the structure of a contact-type dry-coupled piezoelectric ultrasonic shear wave probe provided by the present invention;

[0023] Figure 3 A schematic diagram of the structure of a contact-type dry-coupled magnetostrictive ultrasonic shear wave probe provided by the present invention;

[0024] Figure 4 A schematic diagram of the principle of exciting shear waves in different directions by a contact-type dry-coupled magnetostrictive ultrasonic shear wave probe provided by the present invention;

[0025] In the above figures: mark 1 represents the dry coupling head, mark 2 represents the ultrasonic excitation element, mark 3 represents the liquid backing layer, mark 4 represents the shell, mark 5 represents the connecting rod, mark 6 represents the negative electrode lead, mark 7 represents the positive electrode lead, mark 8 represents the piezoelectric vibrator, and mark 9 represents the magnetostrictive vibrator. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0027] The invention provides a contact-type dry-coupled ultrasonic shear wave probe, which can be used on a rough surface in a dry-coupled and point-contact manner without using a shear wave probe coupling agent.

[0028] The structure of the dry-coupled piezoelectric ultrasonic shear wave probe provided by the present invention is shown in the figure Figure 1 As shown, in this embodiment, the ultrasonic shear wave probe includes a dry coupling head 1, an ultrasonic excitation element 2, a liquid backing layer 3, a shell 4 and a connecting rod 5. The characteristics and main functions of each part are respectively introduced below.

[0029] First, let me introduce the characteristics and main functions of the dry coupling head 1:

[0030] The dry coupling head 1 is a hemisphere, and its front end makes point contact with the object to be tested, replacing the surface contact of the traditional ultrasonic shear wave probe. The ultrasonic shear wave probe provided by the present invention is coupled with the object to be tested by the dry coupling head using dry coupling and point contact, and can be used directly on a rough surface without using a shear wave probe coupling agent or grinding the surface of the object to be tested. In addition, point contact can also make the sound field distribution of the ultrasonic shear wave emitted by the probe approximate to a point sound source, with omnidirectionality, and can meet the detection needs inside a larger object to be tested.

[0031] The dry coupling head 1 is also used to conduct ultrasonic signals between the ultrasonic excitation element 2 and the object to be tested. The object to be tested can be referred to as a workpiece to be tested or a material to be tested. In order to ensure the conduction effect of the ultrasonic signal, the material of the dry coupling head 1 can be selected according to the characteristic acoustic impedance of the object to be tested and the working environment of the probe. For example, if the object to be tested is a workpiece made of alloy, the material of the dry coupling head can be selected from the alloy; if the object to be tested is ceramic, the material of the dry coupling head can be selected from wear-resistant ceramic; if the probe works in a high temperature, corrosive environment for a long time, a material with corrosion resistance and thermal stability such as Hastelloy can be selected.

[0032] The dry coupling head 1 is also used to protect the ultrasonic excitation element 2 to prevent the ultrasonic excitation element 2 from being contaminated or damaged in the working environment.

[0033] The above are the characteristics and usage of the dry coupling head. Next, the characteristics, classification and main usage of the ultrasonic excitation element 2 are introduced:

[0034] The ultrasonic excitation element 2 is attached to the dry coupling head 1 to realize the emission and reception of ultrasonic waves, and specifically includes:

[0035] Ultrasonic emission: When the ultrasonic excitation element 2 is powered, it generates stretching vibrations under the stimulation of electric pulses according to the inverse piezoelectric effect or the forward magnetostrictive effect, which is ultrasonic waves, in which the propagation direction of the transverse wave is perpendicular to the vibration direction. In this process, the electrical signal is converted into an ultrasonic signal.

[0036] Ultrasonic wave reception: When the ultrasonic wave from the inside of the object to be tested acts on the surface of the ultrasonic excitation element, the ultrasonic excitation element is forced to vibrate. According to the positive piezoelectric effect or the reverse magnetostrictive effect, the surface of the ultrasonic excitation element 2 generates an electrical signal related to the vibration, and then transmits the electrical signal to the circuit system through the electrode lead. In this process, the ultrasonic signal is converted into an electrical signal.

[0037] In some embodiments, the ultrasonic excitation element 2 is a piezoelectric vibrator 8. A probe using a piezoelectric vibrator as an ultrasonic excitation element is called a piezoelectric ultrasonic shear wave probe. The piezoelectric ultrasonic shear wave probe can generate low-frequency ultrasonic shear waves, which can effectively reduce the sound attenuation during the propagation of shear waves.

[0038] Figure 2 FIG. 2 shows a piezoelectric ultrasonic shear wave probe structure provided by an embodiment of the present invention. Figure 2 As shown, the piezoelectric vibrator is composed of two parallel-bonded transmitting-receiving piezoelectric chips, each of which adopts a thickness-direction polarization mode. The two piezoelectric chips generate low-frequency vibrations with a shearing tendency under the excitation of electric fields in opposite directions, thereby exciting ultrasonic shear waves to be incident on the object to be tested. The piezoelectric ultrasonic shear wave probe also includes a negative electrode lead 6 and a positive electrode lead 7, which are used to conduct electrical signals between the ultrasonic shear wave probe and the external control end. The positive electrode lead 7 is led out from the bonding surface of the two chips, and the negative electrode lead 6 connects the surfaces of the two chips opposite to the bonding surface and leads out.

[0039] In some embodiments, the ultrasonic excitation element 2 is a magnetostrictive vibrator 9. Hereinafter, a probe using a magnetostrictive vibrator as an ultrasonic excitation element is referred to as a magnetostrictive ultrasonic shear wave probe.

[0040] Figure 3 FIG. 2 shows the structure of a magnetostrictive ultrasonic shear wave probe provided by an embodiment of the present invention. Figure 3As shown, the magnetostrictive vibrator 9 is composed of two magnetostrictive material rods placed in parallel, and the two magnetostrictive material rods are fixed on the dry coupling head 1. Under the excitation of a given electrical signal, the two magnetostrictive material rods vibrate upward and downward in the vertical direction respectively, driving the front dry coupling head 1 to generate a vibration with a shearing tendency in the horizontal direction, thereby exciting the ultrasonic shear wave to be incident on the object to be measured.

[0041] In the magnetostrictive ultrasonic shear wave probe, by adjusting the placement of the magnetostrictive vibrator 9, shear wave propagation in different horizontal directions can be achieved. The principle diagram of this process is shown in FIG. Figure 4 As shown. By placing a group of magnetostrictive material rods in the horizontal direction, vibration with a shearing tendency can be generated in the horizontal direction, thereby exciting transverse waves in the horizontal direction; similarly, placing a group of magnetostrictive material rods in the longitudinal direction can also achieve longitudinal transverse wave excitation. In addition, electrical signals with different amplitudes and phases can be given to the magnetostrictive vibrators 9 in the horizontal and longitudinal directions, respectively, so as to couple the transverse and longitudinal excited transverse wave signals and realize transverse wave propagation in any horizontal direction.

[0042] The above introduces the characteristics, classification and main usage of the ultrasonic excitation element 2. Next, the other parts of the contact-type dry-coupled ultrasonic shear wave probe are introduced, including the liquid backing layer 3, the shell 4 and the connecting rod 5:

[0043] The liquid backing layer 3 wraps the ultrasonic excitation element 2 and is used to absorb the ultrasonic waves emitted by the ultrasonic excitation element 2 to prevent excessive interference of clutter on the signal acquisition of the piezoelectric ultrasonic shear wave straight probe; and produces a damping effect to stop the ultrasonic shear wave probe from vibrating as soon as possible after emitting an ultrasonic pulse.

[0044] The housing 4 is used to encapsulate and protect the liquid backing layer 3 and the ultrasonic excitation element 2. The housing 4 is connected to the dry coupling head 1 and the connecting rod 5 at both ends of the exterior, and is also used to transmit the pressure provided by the connecting rod 5 to the dry coupling head 1.

[0045] The connecting rod 5 is used to apply pressure to the ultrasonic shear wave straight probe so that the dry coupling head fits the workpiece as closely as possible, thereby enhancing the coupling between the dry coupling head and the object to be measured, thereby improving the energy utilization rate of the ultrasonic wave.

[0046] As can be seen from the above, the ultrasonic shear wave probe provided by the present invention realizes dry point contact coupling of the object to be tested through a dry coupling head. It can still be used in situations where the object to be tested cannot be processed or the coupling agent is not suitable for use during the test. For general objects to be tested, the process of grinding the surface of the object to be tested can also be omitted. In addition, the sound field distribution of the shear wave emitted by the ultrasonic shear wave probe provided by the present invention is similar to that of a point sound source, has omnidirectionality, and can meet the detection needs inside larger objects to be tested.

[0047] In the description of the embodiments of the present application, words such as "exemplary", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "for example" or "for example" is intended to present related concepts in a concrete way.

[0048] In the description of the embodiments of the present application, the term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, B exists alone, and A and B exist at the same time. In addition, unless otherwise specified, the term "plurality" means two or more.

[0049] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. The terms "include", "comprises", "has" and their variations all mean "including but not limited to", unless otherwise specifically emphasized.

[0050] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solution of the present invention should be included in the scope of protection of the present invention.

Claims

1. An ultrasonic shear wave probe, characterized in that: It comprises a dry coupling head (1) and an ultrasonic excitation element (2), wherein: The dry coupling head (1) is a hemispherical body, and is used to couple the ultrasonic shear wave straight probe and the object to be measured by dry coupling and point contact, and to conduct ultrasonic signals between the ultrasonic excitation element (2) and the object to be measured; The ultrasonic excitation element (2) is fitted to the dry coupling head (1) to achieve the emission and reception of ultrasonic waves.

2. The ultrasonic shear wave probe according to claim 1, characterized in that: The ultrasonic shear wave probe further comprises a liquid backing layer (3) and a shell (4), wherein: The liquid backing layer (3) wraps the ultrasonic excitation element (2) and is used to absorb the ultrasonic waves emitted by the ultrasonic excitation element (2) to prevent excessive interference of clutter with the signal acquisition of the piezoelectric ultrasonic shear wave straight probe; and to produce a damping effect so that the ultrasonic shear wave probe stops vibrating as soon as possible after emitting an ultrasonic pulse; The housing (4) encapsulates the liquid backing layer (3) and the ultrasonic excitation element (2), and fixes the dry coupling head (1) on the outside.

3. The ultrasonic shear wave probe according to claim 2, characterized in that: The ultrasonic shear wave probe further comprises a connecting rod (5), wherein: The two ends of the housing (4) are respectively connected to the dry coupling head (1) and the connecting rod (5), and are also used to transmit the pressure provided by the connecting rod (5) to the dry coupling head (1); The connecting rod (5) is used to apply pressure to the ultrasonic shear wave probe to enhance the coupling between the dry coupling head and the object to be measured.

4. The ultrasonic shear wave probe according to claim 1, characterized in that: The ultrasonic excitation element (2) is a piezoelectric vibrator (8).

5. The ultrasonic shear wave probe according to claim 4, characterized in that: The piezoelectric vibrator is composed of two identical piezoelectric chips laminated in parallel.

6. The ultrasonic shear wave probe according to claim 5, characterized in that: The ultrasonic shear wave probe further comprises a negative electrode lead (6) and a positive electrode lead (7); The positive electrode lead (7) is led out from the bonding surface of the two wafers, and the negative electrode lead (6) is connected to the surfaces of the two wafers opposite to the bonding surface and led out; The negative electrode lead (6) and the positive electrode lead (7) are used to conduct electrical signals between the ultrasonic shear wave probe and an external control terminal.

7. The ultrasonic shear wave probe according to claim 1, characterized in that: The ultrasonic excitation element (2) is a magnetostrictive vibrator (9).

8. The ultrasonic shear wave probe according to claim 7, characterized in that: The magnetostrictive vibrator (9) is composed of two magnetostrictive material rods placed in parallel, and the two magnetostrictive material rods are fixed on the dry coupling head (1).

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