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Point-Source/Point-Receiver Materials Testing

  • Wolfgang Sachse
  • Kwang Yul Kim

Abstract

Conventional measurements in the ultrasonic testing of materials, when used as the basis of a materials characterization procedure, typically rely on one or two piezoelectric transducers operating as source and receiver, attached to a specimen to launch and detect ultrasonic waves in the object to be characterized. Measurements of signal arrival time (or velocity) and amplitude (or attenuation), possibly as a function of frequency, are then correlated with the composition and the macro- and micro-structure of the material, which may include voids, flaws and inclusions distributed through a region of the material. While relative measurements of the time-of- flight and ultrasonic amplitudes do not present extraordinary measurement challenges, absolute measurements do. It is unfortunate that absolute quantities are often required since they are difficult to obtain reliably with a conventional piezoelectric transducer-based ultrasonic system. For this reason, a considerable effort over the past decade has been undertaken to develop and improve non-contact methods for generating and detecting ultrasonic signals in materials. However, a limiting factor of all the existing non-contact measurement systems is the care required for their use and their reduced sensitivity in comparison to those utilizing piezoelectric transducers.

Keywords

Acoustic Emission Acoustic Emission Signal Piezoelectric Transducer Wave Arrival Magnitude Spectrum 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • Wolfgang Sachse
    • 1
  • Kwang Yul Kim
    • 1
  1. 1.Department of Theoretical and Applied MechanicsCornell UniversityNew YorkUSA

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