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An anisotropic ultrasonic transducer for Lamb wave applications
Smart Structures and Systems, 2016An anisotropic ultrasonic transducer is proposed for Lamb wave applications, such as passive damage or impact localization based on ultrasonic guided wave theory. This transducer is made from a PMNPT single crystal, and has different piezoelectric coefficients d31 and d32, which are the same for the conventional piezoelectric materials, such as Lead ...
Wensong Zhou, Hui Li, Fuh-Gwo Yuan
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Ultrasonic Lamb Wave Inspection Using Fiber Bragg Gratings
2008 China-Japan Joint Microwave Conference, 2008A new ultrasonic Lamb wave nondestructive testing (NDT) system is developed in this paper. The basic idea is to use fiber Bragg gratings (FBG) sensors as acoustic receivers of ultrasonic Lamb waves. The spectral response of fiber Bragg gratings (FBGs) subjected to the ultrasonic field has been theoretically and numerically investigated.
Zhang Haiyan +4 more
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Propagation of ultrasonic Lamb waves in piezoelectric plates
Journal of Applied Physics, 1991The propagation of the lowest-order symmetric (S0) and antisymmetric (A0) Lamb wave modes in a piezoelectric plate is investigated both theoretically as well as experimentally. The characteristics of the modes and their relation to the surface acoustic wave is modified by electrical boundary conditions on the plate surfaces.
S. G. Joshi, Y. Jin
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Lamb wave devices using capacitive micromachined ultrasonic transducers
Applied Physics Letters, 2001Lamb wave devices based on capacitive micromachined ultrasonic transducers (CMUTs) have been built on 500-μm-thick silicon wafers for frequencies in the vicinity of 1 MHz. CMUTs have been used to both excite and detect Lamb waves in the substrate. This configuration eliminates the need for piezoelectric materials, which are not compatible with the ...
G. G. Yaralioglu +5 more
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A multisensor employing an ultrasonic Lamb-wave oscillator
IEEE Transactions on Electron Devices, 1988Initial experimental, analytical, and numerical evaluations of a microsensor that uses ultrasonic Lamb waves propagating in a thin plate supported by a silicon die are presented. Changes of oscillator frequency indicate magnitudes of the variables sensed.
S.W. Wenzel, R.M. White
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Excitation of ultrasonic Lamb waves in piezoelectric plates
Journal of Applied Physics, 1991The excitation of ultrasonic Lamb waves by an interdigital transducer (IDT) deposited on a piezoelectric plate is analyzed using the Green’s-function method. The amplitudes of the generated Lamb waves are obtained in terms of the charge density on transducer electrodes.
S. G. Joshi, Y. Jin
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Coupling of interdigital transducer to ultrasonic Lamb waves
Applied Physics Letters, 1991The coupling of an interdigital transducer to ultrasonic Lamb waves propagating in a piezoelectric plate has been calculated using Green’s function method. It is found that when the plate thickness is more than a few acoustic wavelengths, the lowest order symmetric (S0) and antisymmetric (A0) modes are almost equally generated. The slight difference in
Yu Jin, Shrinivas G. Joshi
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Nonlinear sensitivity of capacitive micromachined ultrasonic Lamb wave transducers
Proceedings of Meetings on Acoustics, 2009A capacitive micromachined Lamb wave transducer using the second-order bending mode of high-aspect rectangular diaphragms to excite and receive Lamb waves in a silicon plate was presented [L. Ge, Proc. SPIE 6358, 1 (2006)]. Thus, the width of the diaphragm is made equal to the wavelength of the A0 wave, and all the transducer parameters can be ...
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Ultrasonic Lamb Waves Applied In Nondestractive Damage Evaluation
2019 13th Symposium on Piezoelectrcity, Acoustic Waves and Device Applications (SPAWDA), 2019Among nondestructive damage testing (NDT) and structural health monitoring (SHM) techniques, the Lamb wave based methods have shown great potential for fast damage detection in plate-like structures. In order to develop Lamb waves based NDE methods, we firstly study the signal processing methods to find a good time-frequency representation (TFR) for ...
Zheng LI +3 more
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Ultrasonic Lamb Wave Measurement and Data Analysis System
Advanced Materials Research, 2012Ultrasonic Lamb wave detection technology is an important, nondestructive testing technology for the damage of plate. In order to inspect the plate material nondestructively, an ultrasonic measurement system is investigated and the principle and structure of the system are described in this paper.
Xiao Chen, Hai Kun Wu
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