NDTnet 1998 Aug, Vol.3 No.8

Abstract

The geometric characterization of material discontinuities by eddy current patterns is generally difficult due to relatively large dimensions of the transducer and its non-linear response [1].
The problem of the transducer dimensions has been solved by using a transducer with orthogonal coils, showing the advantage of the presence of a very sharp peak when the coil perpendicular to the plane of the material under test crosses the discontinuity [2,3].
The geometric characterization is accomplished by studying the dispersion of the electromagnetic field created by the transducer [4], on the existing material discontinuities, by a procedure similar to the eddy current holography [5].
The theoretical results have been verified on different shapes of discontinuities machined in a block of aluminium-magnesium. alloy, the experimental data being obtained by means of a SFT 6000N eddy current equipment.

References


1. Bowler, J., Nondestructive Testing of Materials, R. Collins et. al. (Eds), 1995, IOS Press.
2. Radu, E., Grimberg, R., Savin, A., Mihalache, 0. Sensors and Actuators, 1997, A59, 201-204.
3. Mihalache, 0., Grimberg, R., Radu, E., Savin, A, Sensors and Actuators, 1997, A59, 213-218.
4. Harfield, N., Bowler J, Nondestructive Testing of Materials, R. Collins et. al. (Eds), 1995, IOS Press
5. Hippler, J. H., Ennert, H., Bernus, L. Journal of Nondestructive Evaluation, 1993, 12, 3:153-162.

Abstract Source:
Book of Abstracts, 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN: 87-986898-0-00

Full-Text Source:
Proceedings of the 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN:

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