CN-121988518-A - Piezoelectric ultrasonic transverse wave transducer for resisting structural scattering interference

Abstract

The application provides a piezoelectric ultrasonic transverse wave transducer for resisting structure scattering interference, which comprises a shell, an inclined wedge, a piezoelectric wafer attached to the inclined wedge and a back lining layer filled in the shell, wherein the material of the back lining layer is uniformly distributed in a region along the front edge and the upper edge of the back lining layer, the inclined wedge is provided with a front wedge surface, an inclined wedge front angle and an inclined wedge rear angle, the front wedge surface is of a saw-tooth structure, the angle range of the inclined wedge rear angle comprises any interval of [29 degrees, 34 degrees ] or [38 degrees, 41 degrees ], and the angle range of the inclined wedge front angle comprises any interval of [60 degrees, 80 degrees ] or [100 degrees, 115 degrees ]. According to the piezoelectric ultrasonic transverse wave transducer for resisting structural scattering interference, through the collaborative design of key structural parameters of the wedge blocks and the backing layer structure, the propagation state of sound waves in the transducer is effectively optimized, the structural scattering interference problem of the piezoelectric ultrasonic transverse wave transducer can be solved, and the anti-interference capability and the detection performance of the piezoelectric ultrasonic transverse wave transducer are improved.

Inventors

• ZHU XINJIE
• LIU YUANYANG
• REN HAOSHENG
• AN XIAOHUI

Assignees

• 北方民族大学

Dates

Publication Date

20260508

Application Date

20260127

Claims (9)

1. 1. A piezoelectric ultrasonic transverse wave transducer for resisting structure scattering interference comprises a shell, an inclined wedge block, a piezoelectric wafer attached to the inclined wedge block and a back lining layer filled in the shell, and is characterized in that, The material of the backing layer is uniformly distributed along the front edge and the upper edge of the backing layer; The wedge block is provided with a front wedge surface, a wedge front angle and a wedge rear angle, wherein the front wedge surface is provided with a saw-tooth structure, the angle range of the wedge rear angle comprises any interval of [29 degrees, 34 degrees ] or [38 degrees, 41 degrees ], and the angle range of the wedge front angle comprises any interval of [60 degrees, 80 degrees ] or [100 degrees, 115 degrees ].
2. 2. The piezoelectric ultrasonic shear wave transducer of claim 1, wherein the angle of the wedge relief angle is 33 ° or 40 °.
3. 3. The piezoelectric ultrasonic shear wave transducer of claim 1, wherein the angle of the wedge rake angle is 65 ° or 115 °.
4. 4. The piezoelectric ultrasonic shear wave transducer of claim 1, wherein the saw tooth structure is a plurality of parallel arranged transverse grooves.
5. 5. The piezoelectric ultrasonic shear wave transducer of claim 1, wherein the saw tooth structure is a plurality of intersecting orthogonal grooves.
6. 6. The piezoelectric ultrasonic shear wave transducer of claim 4 or 5, wherein the depth h of the grooves in the saw tooth structure satisfies the following relationship: And lambda is the sound wave wavelength corresponding to the central frequency of the transducer.
7. 7. The piezoelectric ultrasonic shear wave transducer of claim 1, wherein the backing layer is formed by curing a mixed material of tungsten powder and epoxy resin in a volume ratio of 0.522-0.638:1.
8. 8. The piezoelectric ultrasonic shear wave transducer of claim 7, wherein the backing layer has a density of 3.94g/cm 3 ± 10%.
9. 9. The piezoelectric ultrasonic transverse wave transducer for resisting structural scattering interference according to claim 1, wherein a positioning clamping groove is formed in the inner side wall of the shell, the inclined wedge is fixed in the shell through the positioning clamping groove, and the shape and the position of the positioning clamping groove are adaptively set according to the angle of the front angle of the inclined wedge.

Description

Piezoelectric ultrasonic transverse wave transducer for resisting structural scattering interference Technical Field The application relates to the technical field of nondestructive testing, in particular to a piezoelectric ultrasonic transverse wave transducer for resisting structural scattering interference. Background Piezoelectric ultrasonic shear wave transducers are devices that utilize the piezoelectric effect to convert electrical energy into mechanical vibrations and propagate the vibrations in the form of shear waves in a medium. The method has important application value in the nondestructive testing fields such as welding structure defect detection, material internal crack detection, thickness measurement and the like. Conventional piezoelectric ultrasonic transverse wave transducers are typically composed of piezoelectric wafers, backing layers, protective films, wedges, and housings. The piezoelectric wafer is excited to produce high frequency vibrations and the vibrational energy is coupled to the surface of the workpiece or medium at a specific angle by a wedge, thereby producing a transverse wave. However, existing piezoelectric ultrasonic shear wave transducers are prone to generate significant structural scattering echoes within them during operation. Specifically, the acoustic wave excited by the piezoelectric wafer undergoes multiple reflections and refractions between the wedge, backing layer and associated interfaces, and some of the acoustic energy is not effectively absorbed and remains inside the transducer, forming a delayed, non-periodic echo signal. The scattered echoes of the structures are often overlapped with the workpiece defect echoes in the time domain, and particularly, obvious interference is generated on detection of micro defects or near-surface defects, so that the detection signal-to-noise ratio and the detection reliability are reduced. In the prior art, aiming at the problems of internal reflection and noise interference of a piezoelectric ultrasonic transverse wave transducer, some proposals have been tried to restrain through structural improvement. For example, US2683821a discloses a shear wave ultrasound transducer that mounts a quartz crystal transducer on a wedge structure to attenuate unwanted reflected echoes generated inside the transducer. Also for example, CN105793674a discloses an ultrasound transducer with a backing having a spatially segmented surface, by spatially segmenting the backing surface, the acoustic reflection is spread out in time, thereby reducing the net amplitude of the internally reflected wave. These schemes alleviate the problem of structural scattering to a certain extent, but for the acoustic wave propagating in the wedge after the piezoelectric wafer is excited, the structural scattering interference caused by the specific propagation path and reflection characteristics of the acoustic wave still needs to be further optimized and solved, and in particular, a high-resolution and high-sensitivity application scenario is required. Therefore, how to effectively inhibit the scattering interference of the structure generated in the piezoelectric ultrasonic transverse wave transducer under the premise of ensuring the transverse wave excitation efficiency is still a technical problem to be solved in the field. Disclosure of Invention The invention aims to provide a piezoelectric ultrasonic transverse wave transducer for resisting structural scattering interference, which can solve the structural scattering interference problem of the piezoelectric ultrasonic transverse wave transducer and improve the anti-interference capability and detection performance of the piezoelectric ultrasonic transverse wave transducer. The application is realized by the following technical scheme, and specifically comprises the following steps: The piezoelectric ultrasonic transverse wave transducer for resisting structure scattering interference comprises a shell, a wedge block, a piezoelectric wafer attached to the wedge block and a back lining layer filled in the shell, wherein the material of the back lining layer is uniformly distributed along the front edge and the upper edge of the back lining layer, the wedge block is provided with a front wedge surface, a wedge front angle and a wedge rear angle, the front wedge surface is of a saw-tooth structure, the angle range of the wedge rear angle comprises any interval of [29 degrees, 34 degrees ] or [38 degrees, 41 degrees ], and the angle range of the wedge front angle comprises any interval of [60 degrees, 80 degrees ] or [100 degrees, 115 degrees ]. According to the scheme, through the collaborative design of key structural parameters of the wedge and the backing layer structure, the sound wave propagation state in the transducer is effectively optimized, the propagation path and the energy distribution of sound waves in the wedge are optimized from the source through limiting the rear angle and the front a