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Combined Shear-Compression Ultrasound Reflection Tomography

  • Mehran Moshfeghi
  • David Hanstead
Part of the Acoustical Imaging book series (ACIM, volume 14)

Abstract

A new imaging technique has been developed for carrying out real-time ultrasound reflection tomography of cylindrical objects. A circular synthetic aperture is realised by object rotation. Two scans are performed, one isonifying the object with compression waves and the other with shear waves. Each scan is processed separately, using convolution backprojection, and the two resultant tomographic images are then superimposed to form the final image. Images of real defects (voids and cracks) in rods and pipes are presented. It is illustrated that certain classes of defects can only be imaged correctly if the compression and shear images are superimposed to complement each other.

Keywords

Shear Wave Compression Wave Shear Velocity Parallel Beam Pulse Transit Time 
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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References

  1. 1.
    S. J. Norton, M. Linzer, “Ultrasonic Reflectivity Tomography Reconstruction with circular transducer arrays”, Ultrasonic Imaging 1 (1979) 154 – 184.CrossRefGoogle Scholar
  2. 2.
    P. D. Hanstead, “Simplified digital synthesis of ultrasonic images”, Proc. R. Soc. Lond. A 374 (1981) 491 – 502.ADSGoogle Scholar
  3. 3.
    L. A. Shepp, B. F. Logan, “The Fourier reconstruction of a head section”, IEEE Trans Nucl Sci. Vol. NS-21(3) (1974) 21 – 43.Google Scholar
  4. 4.
    K. Liang, B. T. Khuri-Yakub, G. S. Kino, “Reflection tomography at 50 and 300 MHz”, IEEE Ultrasonic symposium (1981) 925 – 929.Google Scholar
  5. 5.
    C. Curry, Geometrical optics, Edward Arnold, London (1956) 31.Google Scholar
  6. 6.
    J. Krautkrämer, H. Krautkrämer, Ultrasonic Testing of Materials, Third revised edition. Springer-Verlag (1983) 329.Google Scholar
  7. 7.
    S. Ganapathy, W. S. Wu, B. Schmult, “Analysis and design considerations for a real-time system for non-destructive evaluation in the nuclear industry”, Ultrasonics. (November 1982) 249 – 256.Google Scholar
  8. 8.
    M. Moshfeghi, P. D. Hanstead, “Ultrasound reflection tomography of cracks in polyester resin”, Proc. of the Vimeiro workshop on Polymer NDE, held at Vimeiro, Portugal, Sept 4–5 1984 (Technomic 1985 to be published).Google Scholar

Copyright information

© Plenum Press, New York 1985

Authors and Affiliations

  • Mehran Moshfeghi
    • 1
  • David Hanstead
    • 1
  1. 1.H. H. Wills Physics LaboratoryUniversity of BristolBristolEngland

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