Piezoelectric transducer capable of omnidirectionally exciting and receiving horizontal shear wave, and preparation method thereof

Abstract

The invention discloses a piezoelectric transducer capable of omnidirectionally exciting and receiving horizontal shear wave, and a preparation method thereof. According to the present invention, a piezoelectric ceramic ring is polarized along a thickness direction and is equally divided into 2n fan-shaped bodies, electrodes are prepared on the side surfaces of the fan-shaped bodies, a ring is reconstructed, the polarizing directions of adjacent transducer subunits are opposite, and the piezoelectric transducer with characteristics of polarizing along the thickness direction, direction alternating and reversing, circumferential electric field applying, and omnidirectional SH0 wave exciting and receiving is formed; various transducer subunits are taken from the same piezoelectric ceramic ring, such that the difference of the polarization degree, the electromechanical coupling coefficient and other material parameters can be ignored so as to ensure the uniformity of the transducer along various directions; the polarization process along the thickness is far more simple than the circumferential polarization; compared to EMAT and MPT, the piezoelectric transducer of the present invention has advantages of high energy conversion rate, strong signal and strong anti-interference ability; and the piezoelectric transducer of the present invention has the strong practical value, and is suitable for the plate detection ultrasonic guided wave detection.

Description

technical field [0001] The invention relates to the field of intelligent materials, in particular to a piezoelectric transducer for omnidirectional excitation and reception of horizontal shear waves and a preparation method. Background technique [0002] Large plate and shell structures are commonly found in structures such as pressure vessels and chemical raw material storage warehouses. Due to corrosion, fatigue damage and other reasons, accidents of this type of structure often occur, causing heavy economic losses and casualties. Therefore, the detection and evaluation of the safety of giant plate shell structures is of great significance. Non-destructive testing and structural health monitoring technology can evaluate the integrity and remaining life of the plate and shell structure, realize timely maintenance, and avoid major safety accidents. Compared with other non-destructive testing techniques, ultrasonic guided wave has attracted more and more attention due to it...

AI Technical Summary

Problems solved by technology

[0005] In order to solve the problems of the existing piezoelectric transducers such as difficulty in circumferential polarization and non-uniform omnidirectional performance, the present invention proposes a piezoelectric transducer for omnidirectional excitation and reception of horizontal shear waves and a preparation method thereof. It overcomes the disadvantages of low energy conversion rate, weak signal, and poor anti-interference ability of MPT and EMAT, and can work in a wide frequency range. use in testing

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