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Title: A Variable Pitch Comb Fixture for Rayleigh Wave Generation and Reception

Abstract

Several methods are available for the generation and reception of Rayleigh waves on a part surface. The use of the so-called 'comb' is one method, where the comb elements or 'fingers' contact the surface with a spacing between adjacent fingers equal to the Rayleigh wavelength of the substrate for a given frequency. Although efficient and simple, a fixed pitch comb is typically useful only at one frequency for a particular substrate. A simple 'parallel link' fixture has been developed where the pitch of the fingers can be varied over a range of spacings, allowing the operator to set the comb pitch for a particular material/frequency at will. The comb elements may be glued to the wear plate of a longitudinal transducer or simply fluid coupled. Elements of the fixture and tests results of the fixtures used for generating Rayleigh waves on aluminum and steel substrates are shown.

Authors:
 [1]
  1. Materials and Engineering Physics Program, Ames Laboratory, USDOE Ames, IA 50011 (United States)
Publication Date:
OSTI Identifier:
21054953
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: 10.1063/1.2718167; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ACOUSTIC TESTING; ALUMINIUM; FLUIDS; PLATES; RAYLEIGH WAVES; SOUND WAVES; STEELS; SUBSTRATES; SURFACES; TRANSDUCERS; WAVELENGTHS; WEAR

Citation Formats

Barnard, Daniel J. A Variable Pitch Comb Fixture for Rayleigh Wave Generation and Reception. United States: N. p., 2007. Web. doi:10.1063/1.2718167.
Barnard, Daniel J. A Variable Pitch Comb Fixture for Rayleigh Wave Generation and Reception. United States. doi:10.1063/1.2718167.
Barnard, Daniel J. Wed . "A Variable Pitch Comb Fixture for Rayleigh Wave Generation and Reception". United States. doi:10.1063/1.2718167.
@article{osti_21054953,
title = {A Variable Pitch Comb Fixture for Rayleigh Wave Generation and Reception},
author = {Barnard, Daniel J.},
abstractNote = {Several methods are available for the generation and reception of Rayleigh waves on a part surface. The use of the so-called 'comb' is one method, where the comb elements or 'fingers' contact the surface with a spacing between adjacent fingers equal to the Rayleigh wavelength of the substrate for a given frequency. Although efficient and simple, a fixed pitch comb is typically useful only at one frequency for a particular substrate. A simple 'parallel link' fixture has been developed where the pitch of the fingers can be varied over a range of spacings, allowing the operator to set the comb pitch for a particular material/frequency at will. The comb elements may be glued to the wear plate of a longitudinal transducer or simply fluid coupled. Elements of the fixture and tests results of the fixtures used for generating Rayleigh waves on aluminum and steel substrates are shown.},
doi = {10.1063/1.2718167},
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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