A Comparison of Millimeter Wave and Eddy Current Detection of Surface Breaking Defects in Conducting Materials

  • S. Ross
  • M. Lusk
  • W. Lord


The detection of surface breaking defects in conducting materials is an important aspect of nondestructive evaluation (NDE). Eddy current NDE methods have been used effectively for the detection of fatigue cracks and other surface breaking flaws in conducting materials [1], however, a detracting characteristic is that the eddy current transducer must be placed in close proximity to the test specimen. Since millimeter wave energy can propagate in air and does not require a couplant, millimeter wave NDE offers an alternative technique with the significant advantage of detection in a stand off mode of operation. Millimeter wave NDE has been shown to be effective at detecting small cracks [2–3], however, some methods under study require that the transducer be in close proximity with the specimen and thus suffer from the same disadvantages as eddy current techniques. This paper compares the detection capabilities of surface breaking flaws on conducting materials for millimeter wave NDE in the stand off mode and conventional eddy current NDE.


Synthetic Aperture Radar Synthetic Aperture Radar Image Eddy Current Test Eddy Current Transducer Eddy Current Probe 
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Copyright information

© Plenum Press, New York 1995

Authors and Affiliations

  • S. Ross
    • 1
  • M. Lusk
    • 2
  • W. Lord
    • 3
  1. 1.Electrical and Computer Engineering DepartmentIowa State UniversityAmesUSA
  2. 2.Division of EngineeringColorado School of MinesGoldenUSA
  3. 3.Electrical and Computer Engineering DepartmentIowa State UniversityAmesUSA

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