Results 1 to 10 of about 129 (113)
Fabrication and Modeling of Matching System for Air-Coupled Transducer
Micromachines, 2022 The tremendous acoustic impedance difference between the piezoelectric composite and air prevents the ultrasonic transition, resulting in low amplitude for the received signal for the composite defect detection using an air-coupled transducer.
Jinjie Zhou, Jiaqi Bai, Yao Liu
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Air-Coupled Piezoelectric Transducers with Active Polypropylene Foam Matching Layers [PDF]
Sensors, 2013 This work presents the design, construction and characterization of air-coupled piezoelectric transducers using 1–3 connectivity piezocomposite disks with a stack of matching layers being the outer one an active quarter wavelength layer made of ...
Tomás E. Gómez Alvarez-Arenas
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Sensors, 2023 Air-coupled ultrasound sensors have advantages over contact ultrasound sensors when a sample should not become contaminated or influenced by the couplant or the measurement has to be a fast and automated inline process.
Klaas Bente +4 more
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“Pipe organ” air-coupled broad bandwidth transducer [PDF]
2017 IEEE International Ultrasonics Symposium (IUS), 2017 Air-coupled transducers are used to conduct fast non-contact inspections in NDT. Normally, the bandwidth of a conventional transducer can be enhanced, but with a cost to its sensitivity. However, low sensitivity is very disadvantageous in air-coupled devices. This paper presents a methodology for improving the bandwidth of an air-coupled micro-machined
Zhu, B. +4 more
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High-frequency air-coupled transducers [PDF]
The Journal of the Acoustical Society of America, 1990 High-frequency air-coupled ultrasonic transducers are used in industrial applications for detecting or ranging with high resolution. The improvement of the coupling between PZT and air is of importance for the transducer performance. Unfortunately, it is difficult to find a material with proper acoustical impedance and small attenuation at high ...
Xiaoqi Bao +2 more
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Sensors, 2021 Ultrasound non-destructive testing (NDT) is a common technique used for defect detection in different materials, from aluminium to carbon-fiber-reinforced polymers (CFRPs).
Marco Boccaccio +4 more
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AIP Advances, 2022 Air-coupled ultrasonic transducers based on novel piezoelectrets with extremely small acoustic impedance have some distinctive advantages including no coupling agent, flexibility, and eco-friendliness, compared to conventional ultrasonic transducers ...
Feng Li +4 more
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Test, modeling, and analysis of air-coupled ultrasonic transducer based on piezoelectret film
AIP Advances, 2020 Piezoelectrets, a new type of electromechanical transducer material with low acoustic impedance and high piezoelectric d33 and g33 coefficients, are promising candidates for developing high-performance air-coupled ultrasonic transducers. In this work, we
Fenglin Zhang +3 more
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Model-Based Analysis and Regulating Approach of Air-Coupled Transducers with Spurious Resonance
Sensors, 2020 As an essential characteristic of air-coupled transducers, electrical impedance can provide valuable information for quality control during manufacturing of transducers.
Xiangxiang Peng +3 more
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Air-Coupled Ultrasonic Spiral Phased Array for High-Precision Beamforming and Imaging
IEEE Open Journal of Ultrasonics, Ferroelectrics, and Frequency Control, 2022 Sparse spiral phased arrays are advantageous for many emerging air-coupled ultrasonic applications, since grating lobes are prevented without being constrained to the half-wavelength element spacing requirement of well-known dense arrays.
Gianni Allevato +6 more
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