Loading...
Signal enhancement in Rayleigh wave interactions using a laser-ultrasound/EMAT imaging system
Author(s)
Dewhurst, R. J.
Date Issued
June 1, 2005
Type
Article
Abstract
Enhancement of signal amplitudes from Rayleigh wave interaction at solid surface features has been investigated when signals were detected by an in-plane electromagnetic acoustic transducer (EMAT). A laser-ultrasound system was used to inspect surface-breaking slots, serving as artificial defects. Nd:YAG laser pulses were delivered onto a metal surface via an optical fiber and focused to a line source by a cylindrical lens. An in-plane EMAT receiver detected transient surface acoustic waves. A-scan signals and B-scan images from surface defects revealed increased signal amplitude up to 2.8 ± 0.3 depending on the distance of the transducer from a slot. An explanation is based on the interaction of the EMAT sensor with the Rayleigh wave. A supporting computer model was derived to show that experimental signal enhancements were consistent with numerical predictions. © 2005 Elsevier B.V. All rights reserved.
Citation
Ultrasonics, 43(7), 512-523, 2005