Inductive and solid-state sensing of pulsed eddy current : a comparative study

  1. Get@NRC: Inductive and solid-state sensing of pulsed eddy current : a comparative study (Opens in a new window)
DOIResolve DOI:
AuthorSearch for:
Proceedings titleInternational Journal of Applied Electromagnetics and Mechanics
Conference16th International Symposium on Applied Electromagnetics and Mechanics (ISEM 2013), July 31-Aug. 2, 2013, Quebec City, Quebec
Pages265271; # of pages: 7
SubjectComparative studies; Magnetic sensing; Non destructive evaluation; Pulsed eddy current
AbstractIn recent years, solid-state devices made their way in the development of electromagnetic non-destructive evaluation (NDE) probes. This fact was evidenced especially for pulsed eddy current, where magneto-resistive and Hall effect devices are used as sensing elements. Their low frequency range and small surface area are suitable to improve the detection of buried and small discontinuities. Although their properties are expected to enhance detectability over simple induction coils, this was still to be proven or demonstrated in a comparative study. This work compares the sensing capabilities of an induction coil to those of two solid-state devices: giant-magneto-resistive (GMR) and Hall effect sensors. All of them are used as detectors in pulsed eddy current probes that have the same excitation mechanism, a ring-type copper coil driven by a constant amplitude square waveform. While the excitation part of the probe is fixed, the sensing components are inter-changeable. Although both induction coils and solid-state sensors output a voltage value as an indication of the magnetic field they are detecting, the voltage for pick-up coils is directly proportional to the rate of change of the magnetic flux. For solid-state sensors the output is in direct relation to the detected magnetic field. Under this study, all three sensing elements are used to detect the driving coil's magnetic output (magnetic field or flux) in air, on planes perpendicular and parallel to the face of the driver coil. The results obtained by all three sensors are quantitatively compared. Then the sensing devices are inserted in the inner space of the driving coil and, subsequently, used for detection of artificially made defects. Finally, the results are compared in terms of magnetic field sensitivity and inspection performance.
Publication date
AffiliationAerospace; National Research Council Canada
Peer reviewedYes
NPARC number21274133
Export citationExport as RIS
Report a correctionReport a correction
Record identifierc0899a19-3603-4efb-b344-43d574395a4f
Record created2015-02-17
Record modified2016-05-09
Bookmark and share
  • Share this page with Facebook (Opens in a new window)
  • Share this page with Twitter (Opens in a new window)
  • Share this page with Google+ (Opens in a new window)
  • Share this page with Delicious (Opens in a new window)