Materials Characterization from Elastic Wave Anisotropy Images
We describe in this paper the use of transient ultrasonic waves to image wave anisotropy effects in single crystal specimens of silicon. The measurements rely on the point-source/point-receiver (PS/PR) technique with a Nd: YAG laser as a scanned source and a point piezoelectric transducer as a detector. The image is based on the measurement of the signal arrival times and corresponding amplitudes of wave groups along various propagation directions in the single crystal specimens. It is found that along some directions there are strong focusing effects. An interpretation of the measured images based on an analysis of elastic waves in anisotropic solids is given. A potential application of this imaging procedure as a materials characterization tool is also shown.
KeywordsAnisotropic Material Ultrasonic Signal Oriented Crystal Crystal Specimen Single Crystal Specimen
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