Effects of Pulse Distortion on Phase Velocity Measurements Using the Zero-Crossing Shift Technique

  • Y. Li
  • R. B. Thompson
Part of the Review of Progress in Quantitative Nondestructive Evaluation book series


One of the technique that is often used in the measurement of phase velocities of guided elastic modes is the zero-crossing shift technique. Using this technique, one measures time delays (usually through a counter) of a specific zero-crossing for a number of different separation distances of two transducers. The phase velocity Vp is computed as the slope of the distance-delay plot. For non-dispersive waves, this produces no problem as the pulse retains its shape as it propagates.


Phase Velocity Pulse Envelope Texture Characterization Lamb Mode Pulse Distortion 
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Copyright information

© Springer Science+Business Media New York 1990

Authors and Affiliations

  • Y. Li
    • 1
  • R. B. Thompson
    • 1
  1. 1.Ames LaboratoryIowa State UniversityAmesUSA

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