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A New Technique for Distinguishing Internal Voids from Solid Inclusions

  • K. I. Maslov
  • T. Kundu
  • O. I. Lobkis

Abstract

An acoustic microscope has been proven to be a very effective tool for visualization and characterization of small internal defects in solids[l]. The distinction of internal defects such as cracks and voids from solid inclusions is sometimes necessary for material evaluation. For example in case of light metal casting alloys ultrasonic scattered echo from pores and heavy metal inclusions used for strengthening purposes can give the ultrasonic signal of the same order of magnitude [2]. In this paper it is shown how the phase information of the reflected echo can be used to distinguish void signals from solid inclusion signals. Conventional acoustic imaging techniques that use only amplitude information and ignores the phase information can not distinguish between voids and inclusions.

Keywords

Longitudinal Wave Reflection Coefficient Spherical Inclusion Solid Inclusion Spherical Void 
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 1996

Authors and Affiliations

  • K. I. Maslov
    • 1
  • T. Kundu
    • 2
  • O. I. Lobkis
    • 1
  1. 1.Institute of Chemical PhysicsRussian Academy of ScienceMoscowRussia
  2. 2.Department of Civil Engineering and Engineering MechanicsUniversity of ArizonaTucsonUSA

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