Non-Contact Ultrasonic Characterization of Defects Using EMATs
- University of Warwick, Dept. of Physics, Coventry CV4 7AL (United Kingdom)
We have developed a non-contact ultrasonic technique for detecting and gauging the depth of surface and subsurface defects in metals. A low-frequency broadband Rayleigh-wave pulse is generated and detected by two electro-magnetic acoustic transducers (EMATs) held at a standoff of up to 5 mm, with laser generation and detection also possible. This technique has applications for online testing such as rail track inspection, where faster speeds than with conventional contact ultrasonic techniques should be possible. We describe experiments gauging the position and depth of cracks by measuring the change in signal amplitude and frequency content with the EMATs on either side of the defect, or by looking for an enhancement of the signal close to the defect.
- OSTI ID:
- 20655350
- Journal Information:
- AIP Conference Proceedings, Vol. 760, Issue 1; Conference: Conference on review of progress in quantitative nondestructive evaluation, Golden, CO (United States), 25-30 Jul 2004; Other Information: DOI: 10.1063/1.1916857; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
- Country of Publication:
- United States
- Language:
- English
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