MATERIAL CHARACTERIZATION USING HERTZIAN POINT CONTACT TRANSDUCERS Sample
نویسندگان
چکیده
Non-destructive Hertzian contacts are used to couple ultrasonic waves for characterization and defect detection in anisotropic solid pates. Spring loaded quartz rods bonded to PZT-5H transducers are used to form a point source point receiver pair and ultrasonic plate modes are excited and detected around 200 KHz with 50 dB signal to ratio at the receiving end. Measurements are performed on silicon wafers and various graphite-epoxy composite plates. The direction dependence and dispersion curves of the zeroth order antisymmetric Lamb wave are measured and excellent agreement with theoretical calculations is observed.
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