| Autor: |
Bowler, A. I., Drinkwater, B. W., Wilcox, P. D. |
| Předmět: |
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| Zdroj: |
AIP Conference Proceedings; 2/28/2008, Vol. 975 Issue 1, p648-655, 8p, 1 Diagram, 6 Graphs |
| Abstrakt: |
The non-destructive measurement of stress and strain is of interest in many engineering applications. It is known that surface displacement, and hence strain, can be measured using the correlation of optical speckle patterns. In this paper a similar approach is adopted, except that correlation is performed on the speckle in high frequency ultrasonic array images. This has the key potential advantage that the internal strains are measured. Experiments are described in which an ultrasonic array was used to generate high resolution speckle images of the scattering from the microstructure within a metallic bar before and after loading. The full matrix of transmit-receive signals from the array was post processed to synthetically focus the array on every point within the field of view. Cross-correlation was then used to find the displacement of the images and the result compared to the known displacement. Strains ranging from 100–700μ were measured over a 10 mm×5 mm field of view. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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