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Title: Ultrasonic Porosity Estimation of Low-Porosity Ceramic Samples

Abstract

We report on efforts to extend the applicability of an airborne ultrasonic pulse-reflection (UPR) method towards lower porosities. UPR is a method that has been used successfully to estimate porosity and tortuosity of high porosity foams. UPR measures acoustical reflectivity of a target surface at two or more incidence angles. We used ceramic samples to evaluate the feasibility of extending the UPR range into low porosities (<35%). The validity of UPR estimates depends on pore size distribution and probing frequency as predicted by the theoretical boundary conditions of the used equivalent fluid model under the high-frequency approximation.

Authors:
;  [1]; ;  [2];  [1];  [3]
  1. Electronics Research Unit, Department of Physical Sciences, University of Helsinki, P.O. Box 64 FIN-00014 (Finland)
  2. Division of Geophysics, Department of Physical Sciences, University of Helsinki, P.O. Box 64 FIN-00014 (Finland)
  3. (Finland)
Publication Date:
OSTI Identifier:
21054946
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 894; Journal Issue: 1; Conference: Conference on review of progress in quantitative nondestructive evaluation, Portland, OR (United States), 30 Jul - 4 Aug 2006; Other Information: DOI: 10.1063/1.2718118; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; APPROXIMATIONS; BOUNDARY CONDITIONS; CERAMICS; DISTRIBUTION; FLUIDS; FOAMS; INCIDENCE ANGLE; POROSITY; PULSES; REFLECTION; REFLECTIVITY; SURFACES; ULTRASONIC TESTING

Citation Formats

Eskelinen, J., Hoffren, H., Kohout, T., Pesonen, L. J., Haeggstroem, E., and Helsinki Institute of Physics, PO Box 64, FIN-00014. Ultrasonic Porosity Estimation of Low-Porosity Ceramic Samples. United States: N. p., 2007. Web. doi:10.1063/1.2718118.
Eskelinen, J., Hoffren, H., Kohout, T., Pesonen, L. J., Haeggstroem, E., & Helsinki Institute of Physics, PO Box 64, FIN-00014. Ultrasonic Porosity Estimation of Low-Porosity Ceramic Samples. United States. doi:10.1063/1.2718118.
Eskelinen, J., Hoffren, H., Kohout, T., Pesonen, L. J., Haeggstroem, E., and Helsinki Institute of Physics, PO Box 64, FIN-00014. Wed . "Ultrasonic Porosity Estimation of Low-Porosity Ceramic Samples". United States. doi:10.1063/1.2718118.
@article{osti_21054946,
title = {Ultrasonic Porosity Estimation of Low-Porosity Ceramic Samples},
author = {Eskelinen, J. and Hoffren, H. and Kohout, T. and Pesonen, L. J. and Haeggstroem, E. and Helsinki Institute of Physics, PO Box 64, FIN-00014},
abstractNote = {We report on efforts to extend the applicability of an airborne ultrasonic pulse-reflection (UPR) method towards lower porosities. UPR is a method that has been used successfully to estimate porosity and tortuosity of high porosity foams. UPR measures acoustical reflectivity of a target surface at two or more incidence angles. We used ceramic samples to evaluate the feasibility of extending the UPR range into low porosities (<35%). The validity of UPR estimates depends on pore size distribution and probing frequency as predicted by the theoretical boundary conditions of the used equivalent fluid model under the high-frequency approximation.},
doi = {10.1063/1.2718118},
journal = {AIP Conference Proceedings},
number = 1,
volume = 894,
place = {United States},
year = {Wed Mar 21 00:00:00 EDT 2007},
month = {Wed Mar 21 00:00:00 EDT 2007}
}
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