A phased electromagnetic acoustic transducer (EMAT) array system has been developed for the detection and characterization of surface-breaking defects. An array of four linear coils that are individually controlled is used to generate a Rayleigh wave. The high-current electronics combined with the coil designs enables the array to generate either narrowband or broadband signals, and controlling the phase delay between the channels makes it possible to change the ultrasound wavelength without requiring the physical separation of the coils to be changed. The experimental results show that the four-coil phased array can generate a wavelength range from 3.0 to 11.7 mm. Surface-breaking defects were characterized using a transmit-receive setup with a broadband EMAT detector being used to detect the Rayleigh wave. Machined surface slots with different depths were used for technique validation. The results show that the array is sensitive to surface defects and a wide depth sensitivity range for defect sizing can be easily achieved by applying phasing to tune the wavelength of operation. A large increase in detection flexibility is immediately shown.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1109/TUFFC.2020.2968151 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Single soliton microcomb combined with optical phased array for parallel FMCW LiDAR.
Nat Commun
January 2025
State Key Laboratory for Extreme Photonics and Instrumentation, International Research Center for Advanced Photonics, Ningbo Innovation Center, College of Optical Science and Engineering, Zhejiang University, Hangzhou, 310058, China.
The frequency-modulated continuous-wave (FMCW) technology combined with optical phased array (OPA) is promising for the all-solid-state light detection and ranging (LiDAR). We propose and experimentally demonstrate a silicon integrated OPA combined with an optical frequency microcomb for parallel LiDAR system. For realizing the parallel wavelengths emission consistent with Rayleigh criterion, the wide waveguide beyond single mode region combined with the bound state in the continuum (BIC) effect is harnessed to obtain an ultra-long optical grating antenna array.
View Article and Find Full Text PDFMicrowave Surface and Lamb Waves in a Thin Diamond Plate: Experimental and Theoretical Investigation.
Ultrasonics
January 2025
Federal State Budgetary Institution , Technological Institute for Superhard and Novel Carbon Materials of National Research Centre, Kurchatov Institute, 108840 Moscow, Troitsk, Russian Federation.
Microwave surface and Lamb waves in a multilayered piezoelectric "Al-IDT/(AlSc)N/(001)[110] diamond" structure designed as a SAW resonator were studied using both the experimental and modeling methods. In this structure, it is possible to generate Rayleigh, surface horizontal (SH) and Lamb waves simultaneously. The successful excitation of Lamb waves at operating frequencies up to 20 GHz has been obtained.
View Article and Find Full Text PDFMicrovascular blood flow ultrasound imaging with microbubble-based H-Scan technology.
Med Biol Eng Comput
January 2025
Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Science, Suzhou, 215613, China.
Ultrasound blood flow imaging plays a crucial role in the diagnosis of cardiovascular and cerebrovascular diseases. Conventional ultrafast ultrasound plane-wave imaging techniques have limited capabilities in microvascular imaging. To enhance the quality of blood flow imaging, this study proposes a microbubble-based H-Scan ultrasound imaging technique.
View Article and Find Full Text PDFElectrokinetic flow instabilities in shear thinning fluids with conductivity gradients.
Soft Matter
January 2025
Department of Mechanical Engineering, Clemson University, Clemson, SC 29634, USA.
Instabilities in the form of periodic or irregular waves at the fluid interface have been demonstrated in microchannel electrokinetic flows with conductivity gradients when the applied electric field is above a threshold value. Most prior studies on electrokinetic instabilities (EKI) are restricted to Newtonian fluids though many of the chemical and biological samples in microfluidic applications exhibit non-Newtonian characteristics. We present in this work an experimental study of the effects of fluid shear thinning on the development of EKI waves through the addition of a small amount of xanthan gum (XG) polymer to both the high- and low-concentration Newtonian buffer solutions.
View Article and Find Full Text PDFEngineering the acoustic field with a Mie scatterer for microparticle patterning.
Lab Chip
January 2025
Key Laboratory of Biomedical Engineering of Ministry of Education, Department of Biomedical Engineering, Zhejiang University, Hangzhou, 310027, China.
The utilization of acoustic fields offers a contactless approach for microparticle manipulation in a miniaturized system, and plays a significant role in medicine, biology, chemistry, and engineering. Due to the acoustic radiation force arising from the scattering of the acoustic waves, small particles in the Rayleigh scattering range can be trapped, whilst their impact on the acoustic field is negligible. Manipulating larger particles in the Mie scattering regime is challenging due to the diverse scattering modes, which impacts the local acoustic field.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!