Structural Optimization of a Piezoelectric Transducer for Selective Guided Wave Excitation

Ultrasonic guided wave inspection technology has been widely for long distance pipeline inspection; however, the pipe elbow’s discontinuous structure and the dispersion of L-type wave are restricting the application of this technology. This paper proposes a method of L(0,2) mode guided wave excitation based on magnetostrictive effect and explores the optimization of the magnetization sensor arrangement. Test results shows that the proposed method can detect many types of defects in the pipe elbow. This paper encourages the use of L(0,2) mode guided wave excitation based on magnetostrictive effect in pipeline site inspections.

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Ultrasonic Nondestructive Evaluation of Stress Corrosion Crack in Welded Steel Plate

Volume 6: Materials and Fabrication ◽

10.1115/pvp2020-21794 ◽

2020 ◽

Author(s):

Zhaoyun Ma ◽

Lingyu Yu ◽

Poh-Sang Lam ◽

Robert L. Sindelar ◽

Andrew J. Duncan ◽

...

Keyword(s):

Carbon Steel ◽

Crack Length ◽

Stress Corrosion ◽

Piezoelectric Transducer ◽

Steel Plate ◽

Guided Wave ◽

Steel Plates ◽

Inspection System ◽

Wave System ◽

Welded Steel

Abstract Stress corrosion cracking (SCC) has been observed in the high-level nuclear waste tanks that were constructed by welding carbon steel plates. This paper aims to establish an ultrasonic inspection system and its fundamental ability for SCC inspection and quantification on thick welded steel plates. A welded steel plate was fabricated without heat treatment by joining two carbon steel plates through gas metal arc welding (GMAW) procedure. SCC growth, which was initiated with starter cracks across the weld, were observed in a few weeks after submerging the plate in 5 molar (5M) sodium nitrate (NaNO3) solution at about 90 °C. The SCC is inspected with an ultrasonic guided wave system, which employs a piezoelectric transducer for guided wave actuation and a scanning laser Doppler vibrometer (SLDV) for wavefield sensing. The measured wavefield can immediately show wave interactions with the crack. Wavefield images are further generated for the crack length quantification. To demonstrate the crack sizing capability of using the piezoelectric transducer and SLDV, the previous results from the magnetic particle test (MT) are compared. Reasonable agreement in crack length measurement is obtained with the ultrasonic test imaging technique.

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SH guided wave excitation by an apparent face-shear mode (d 36) piezocomposite transducer: experiments and theory

Smart Materials and Structures ◽

10.1088/1361-665x/ab4ab3 ◽

2019 ◽

Vol 28 (11) ◽

pp. 115045 ◽

Cited By ~ 4

Author(s):

Hongchen Miao ◽

Lei Xu ◽

Hao Zhang

Keyword(s):

Guided Wave ◽

Shear Mode ◽

Wave Excitation

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Influence of a delamination on Lamb wave excitation by a nearby piezoelectric transducer

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x20919977 ◽

2020 ◽

pp. 1045389X2091997 ◽

Cited By ~ 2

Author(s):

Alisa N Shpak ◽

Mikhail V Golub ◽

Inka Mueller ◽

Artem Eremin ◽

Jens Kathol ◽

...

Keyword(s):

Mathematical Model ◽

Piezoelectric Transducer ◽

Lamb Wave ◽

Lamb Waves ◽

Boundary Integral ◽

Experimental Investigations ◽

Wave Excitation ◽

Damage Scenarios ◽

Active Sensor ◽

Piezoelectric Wafer

This article presents the results of theoretical and experimental investigations of characteristic changes of Lamb wave excitation and scattering by a strip-like horizontal delamination in a layered elastic waveguide for Lamb waves induced by a piezoelectric wafer active sensor. The boundary integral equation method is used to describe wave propagation in an infinite layered waveguide with a delamination, while the frequency domain spectral element method is employed to model the dynamic behaviour of the piezoelectric wafer active sensor, which allows to simulate debonding between the piezoelectric wafer active sensor and the waveguide. Experimental investigations of the dynamic interaction of the piezoelectric wafer active sensor with a layered plate containing a horizontal delamination is conducted for several damage scenarios, showing a good agreement with the results obtained using the developed mathematical model. The obtained mathematical model is employed to analyse alteration of the piezo-induced Lamb waves including modes’ decomposition due to delamination. The conversion and/or conservation of the Lamb waves on account of a delamination is investigated. The electro-mechanical impedance of the piezoelectric transducer and the stress intensity factors of a delamination are analysed in dependence on the delamination location.

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