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Title: Hidden Crack Detection with GMR Sensing of Magnetic Fields from Eddy Currents

Abstract

A giant magneto-resistive (GMR) sensor placed inside a coil has been used for same side eddy current measurements on metallic plates. Magnetic fields from eddy currents generated in these metallic plates by excitation of the coil, are detected by the GMR sensor. The signal excitation and detection is accomplished using a lock-in amplifier which allows independent measurement of the phase and magnitude. The sensor configuration has been used to detect notches. Phase and magnitude images acquired with this sensor configuration are compared with the images obtained using the coil only.

Authors:
;  [1]; ;  [2]
  1. Structural Integrity Division, University of Dayton Research Institute, 300 College Park Drive, Dayton, Ohio 45469-0120 (United States)
  2. Metals, Ceramics, and NDE Division, Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio 45433 (United States)
Publication Date:
OSTI Identifier:
21054965
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: 10.1063/1.2717983; (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; ALLOYS; CRACKS; DETECTION; EDDY CURRENT TESTING; EDDY CURRENTS; EXCITATION; IMAGES; LOCK-IN AMPLIFIERS; MAGNETIC FIELDS; MAGNETORESISTANCE; PLATES; SENSORS

Citation Formats

Ko, Ray T., Sathish, Shamachary, Knopp, Jeremy S., and Blodgett, Mark P. Hidden Crack Detection with GMR Sensing of Magnetic Fields from Eddy Currents. United States: N. p., 2007. Web. doi:10.1063/1.2717983.
Ko, Ray T., Sathish, Shamachary, Knopp, Jeremy S., & Blodgett, Mark P. Hidden Crack Detection with GMR Sensing of Magnetic Fields from Eddy Currents. United States. doi:10.1063/1.2717983.
Ko, Ray T., Sathish, Shamachary, Knopp, Jeremy S., and Blodgett, Mark P. Wed . "Hidden Crack Detection with GMR Sensing of Magnetic Fields from Eddy Currents". United States. doi:10.1063/1.2717983.
@article{osti_21054965,
title = {Hidden Crack Detection with GMR Sensing of Magnetic Fields from Eddy Currents},
author = {Ko, Ray T. and Sathish, Shamachary and Knopp, Jeremy S. and Blodgett, Mark P.},
abstractNote = {A giant magneto-resistive (GMR) sensor placed inside a coil has been used for same side eddy current measurements on metallic plates. Magnetic fields from eddy currents generated in these metallic plates by excitation of the coil, are detected by the GMR sensor. The signal excitation and detection is accomplished using a lock-in amplifier which allows independent measurement of the phase and magnitude. The sensor configuration has been used to detect notches. Phase and magnitude images acquired with this sensor configuration are compared with the images obtained using the coil only.},
doi = {10.1063/1.2717983},
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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