Guided Ultrasound Inspection of Small Features Using a Horn-Type Transducer Design

Costa, M.; Schaal, Christoph

doi:10.1007/s11340-022-00915-w

Cited by 1 publication

(2 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, internal reflections due to a lack of an attenuating backing cause significant ringing when using this transducer for guided wave excitation. 11 Proc. of SPIE Vol.…”

Section: Transducer Characterizationmentioning

confidence: 99%

See 1 more Smart Citation

On detecting regional inhomogeneity in composite plates using Lamb waves

Schaal

Chow

Logozzo

et al. 2023

Health Monitoring of Structural and Biological Systems XVII

View full text Add to dashboard Cite

It is well known that guided ultrasonic waves are suitable to detect damages in composite plates. It has also been shown that these Lamb waves can be utilized to infer material properties through nondestructive measurements. More recently, it was shown that this may be used to determine regional inhomogeneity that is inherent to composite materials due to manufacturing imperfections. In this project, it is investigated whether automated processing of Lamb wave-based data is generally suitable to detect such imperfections. Woven prepreg and short-fiber composite panels are manufactured. A large set of nondestructive measurements are conducted to determine dispersion and attenuation characteristics for multiple regions across each panel. Automated signal processing is performed to extract characteristic features of the signal, which are in turn used to identify any differences within the panels. Moreover, it is studied which type of sensing technology, such as contact transducers, air-coupled transducers or a laser Doppler vibrometer are most suitable for this task. That is, ultrasound measurements with different actuator and sensor combinations are accompanied by additional transducer characterization measurements. Optimal frequency ranges for each transducer are determined in addition to studying potential effects of transducer orientation. Based on all findings, it can be concluded that detecting regional inhomogeneity remains challenging due to various compounding limitations, such as optimal transducer frequency ranges, human error and generally low signal-to-noise ratios in Lamb wave-based measurements, especially at longer propagation distances. In turn, the development of guided wave-based nondestructive evaluation methods require a holistic approach with careful considerations of the employed transducers.

show abstract

“…However, internal reflections due to a lack of an attenuating backing cause significant ringing when using this transducer for guided wave excitation. 11 Proc. of SPIE Vol.…”

Section: Transducer Characterizationmentioning

confidence: 99%

“…10 However, these transducers are often bulky and are difficult to use on curved surfaces. 11 More recently, air-coupled transducers have been employed for a variety of applications and show great promise despite their reduced sensitivity. 12 Laser ultrasonics have been employed both for actuation 13 and sensing.…”

Section: Introductionmentioning

confidence: 99%