An Active Matched Thickness Molded Piezoelectric-Pneumatic Coupled Ultrasonic Transducer

Abstract

The invention provides an active matching thickness mould pressing electropneumatic coupling ultrasonic transducer. The active matching thickness mould pressing electropneumatic coupling ultrasonic transducer comprises a piezoelectric plate (1), a first matching layer (2), a second matching layer (3), a transducer shell (4), a first joint (5) and a second joint (6); the piezoelectric plate (1), the first matching layer (2) and the second matching layer (3) are sequentially arranged in the transducer shell (4) in the emission direction of ultrasonic signals, the first matching layer (2) is of a round sheet structure made of microhole foaming materials, the second matching layer (3) is of a round sheet structure made of a polarization multi-hole PVDF thin film, the second matching layer (3) is communicated with the second joint (6) through a wire, and the diameter of the first matching layer (2) and the diameter of the second matching layer (3) are the same with that of the piezoelectric plate (1). According to the transducer, an active matching layer material is introduced, transmission sound waves can be actively amplified, and the sensitivity can be improved.

Description

technical field [0001] The invention relates to the technical field of ultrasonic non-destructive testing, in particular to an active-matched thickness molded piezoelectric electric-pneumatic coupling ultrasonic transducer. Background technique [0002] Thickness-molded piezoelectric-pneumatic-coupled ultrasonic transducers are the core components of an important non-contact ultrasonic testing technology and have broad application prospects. The difficulty of its core technology is mainly reflected in the serious mismatch between the acoustic impedance of the piezoelectric sheet and the air, resulting in low efficiency of acoustic energy radiation of the transducer and low sensitivity of receiving voltage. Traditional solutions generally use low acoustic impedance materials such as microporous foam materials and silicon aerogels as matching layers. The commonly used matching layer materials of air-coupled ultrasonic transducers reported abroad include porous materials such ...

AI Technical Summary

Problems solved by technology

[0003] The object of the present invention is to provide an active matching thickness molded piezoelectric electric-pneumatic coupling ultrasonic transducer for the technical problem of low sensitivity of the existing thickness-molded piezoelectric electric-pneumatic Source matching method, establish a theoretical model of active matching, introduce active devices as matching layer materials, and carry out "active" amplification of transmitted sound waves on the basis of retaining the traditional enhanced sound wave transmission effect, and further improve air-coupled ultrasonic conversion. Sensitivity of the transducer

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