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Title: Acoustic Characterization and Impact Sensing for Ceramic Thermal Protection Systems (TPS)

Abstract

A study was conducted to understand acoustic wave propagation characteristics in a ceramic matrix composite (CMC) wrapped tile thermal protection system (CMC+ Foam+ RTV+ SIP+ RTV+ Al) and ceramic foam. Sound velocities were measured in three orthogonal directions on the above material. The attenuation coefficients were also determined for a uncoated ceramic foam. Commercially available standard acoustic emission transducers, piezo-wafers and polymer based PVDF (polyvinylidiene fluoride) film were employed in the experiments to acquire the acoustic data. The performance characteristics of these sensors will be discussed in light of impact detection. Variation in the wave propagation characteristics along different directions and the role of processing in causing anisotropic acoustic properties in thermal protection systems will be discussed.

Authors:
 [1]; ;  [2];  [3]
  1. Anteon Corporation, 5100 Springfield St, Suite 509, Dayton, OH, 45431 (United States)
  2. University of Dayton Research Institute, 300 College Park, Dayton, OH, 45469 (United States)
  3. Air Force Research Laboratory, Materials and Manufacturing Directorate (AFRL/MLL), Wright-Patterson AFB, OH 45433 (United States)
Publication Date:
OSTI Identifier:
20798243
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 820; Journal Issue: 1; Conference: Conference on review of progress in quantitative nondestructive evaluation, Brunswick, ME (United States), 31 Jul - 5 Aug 2005; Other Information: DOI: 10.1063/1.2184732; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CERAMICS; COMPOSITE MATERIALS; FOAMS; ORGANIC FLUORINE COMPOUNDS; POLYMERS; SAFETY; SOUND WAVES; THERMAL TESTING; VELOCITY; WAVE PROPAGATION

Citation Formats

Kuhr, S. J., Reibel, R., Sathish, S., and Jata, K. V. Acoustic Characterization and Impact Sensing for Ceramic Thermal Protection Systems (TPS). United States: N. p., 2006. Web. doi:10.1063/1.2184732.
Kuhr, S. J., Reibel, R., Sathish, S., & Jata, K. V. Acoustic Characterization and Impact Sensing for Ceramic Thermal Protection Systems (TPS). United States. doi:10.1063/1.2184732.
Kuhr, S. J., Reibel, R., Sathish, S., and Jata, K. V. Mon . "Acoustic Characterization and Impact Sensing for Ceramic Thermal Protection Systems (TPS)". United States. doi:10.1063/1.2184732.
@article{osti_20798243,
title = {Acoustic Characterization and Impact Sensing for Ceramic Thermal Protection Systems (TPS)},
author = {Kuhr, S. J. and Reibel, R. and Sathish, S. and Jata, K. V.},
abstractNote = {A study was conducted to understand acoustic wave propagation characteristics in a ceramic matrix composite (CMC) wrapped tile thermal protection system (CMC+ Foam+ RTV+ SIP+ RTV+ Al) and ceramic foam. Sound velocities were measured in three orthogonal directions on the above material. The attenuation coefficients were also determined for a uncoated ceramic foam. Commercially available standard acoustic emission transducers, piezo-wafers and polymer based PVDF (polyvinylidiene fluoride) film were employed in the experiments to acquire the acoustic data. The performance characteristics of these sensors will be discussed in light of impact detection. Variation in the wave propagation characteristics along different directions and the role of processing in causing anisotropic acoustic properties in thermal protection systems will be discussed.},
doi = {10.1063/1.2184732},
journal = {AIP Conference Proceedings},
number = 1,
volume = 820,
place = {United States},
year = {Mon Mar 06 00:00:00 EST 2006},
month = {Mon Mar 06 00:00:00 EST 2006}
}
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