Journal of Nondestructive Evaluation

, Volume 3, Issue 3, pp 125–136 | Cite as

On the optimum applied field for magnetic particle inspection using direct current

  • C. L. Oehl
  • L. J. Swartzendruber


Experimental measurements of leakage fields from cylindrical defects were obtained in a geometry which permitted simultaneous measurement of the magnetic induction of the material. The results obtained are compared with calculations using a nonlinear finite difference method. Both the experiments and the calculations indicate that the magnitude of the leakage field continues to grow nearly in proportion with the applied field well into the saturation region of the magnetic material. The implications for magnetic particle inspection are discussed.

Key words

magnetic particle inspection magnetic leakage fields finite difference method NDE 


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Copyright information

© Plenum Publishing Corporation 1982

Authors and Affiliations

  • C. L. Oehl
    • 1
  • L. J. Swartzendruber
    • 1
  1. 1.National Measurement LaboratoryNational Bureau of StandardsWashington, DC

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