Interaction of ultrasonic waves with surface-breaking defects
| Autor: | R. S. Edwards, M. H. Rosli, Francisco Hernandez-Valle, A. R. Clough |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
Surface (mathematics)
Materials science business.industry 020206 networking & telecommunications 02 engineering and technology Laser Signal law.invention Amplitude Optics Transducer Position (vector) law Surface wave 0202 electrical engineering electronic engineering information engineering 020201 artificial intelligence & image processing Ultrasonic sensor business |
| Zdroj: | AIP Conference Proceedings |
| ISSN: | 0094-243X |
| DOI: | 10.1063/1.4914750 |
| Popis: | It is well known that surface-breaking defects can be characterised using ultrasonic surface waves. The transmitted amplitude of the waves in the region of a defect is related to the frequency content of the wave, the sample thickness, and the defect depth, while an enhanced signal is observed close to the defect opening due to several effects, including constructive interference of incident and reflected waves. We present measurements of surface-breaking defects in metal samples using non-contact ultrasonic techniques (electromagnetic acoustic transducers (EMATs) and lasers). The use of non-contact transducers allows easy scanning of samples, in order to study defect interactions in both the near- and far-field relative to the defect position. The effect of geometry and position of the defect (for example straight slots, angled slots, and branched slots) is studied, and compared to the behaviour of the methods on real defects. The benefits of the non-contact techniques for crack characterisation are highlighted, including the ability to measure separately the in-plane and out-of-plane components of the wave velocity. The scanning approach also gives a simple method of locating defects on the sample surface. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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