Abstract
Difficulties often occur in eddy current inspection when a defect is situated close to an edge. This is due to the large signal arising from the edge (‘edge-effect’) which tends to obscure any signals coming from the defect [1,2]. To understand the edge-effect in eddy current NDI in more detail, the induction of eddy currents in a conducting 90° edge by a two-dimensional coil is considered in this paper. Firstly, the impedance of a two-dimensional coil in the vicinity of a conducting quarter-space is calculated numerically using a dual boundary-integral-equation (BIE) method and the results compared with experiment. The behaviour of the induced currents (vector potential) in the vicinity of the edge is then examined using the numerical (BIE) results and the results of an analytical approximation [3] valid in the limit of small skin-depth.
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References
B. C. Bishop and N. T. Goldsmith, Non-Destructive Testing Australia 21 2 6–8 (1984).
D. J. A. Williams, J. P. Tilson and J. Blitz, Effects of the Edges of Samples on Eddy-Current Flaw Evaluation, in Proceedings of Fourteenth Symposium on Nondestructive Evaluation, ( San Antonio, Texas, 1983 ).
S. K. Burke, J. Phys. D: Appl. Phys. 18 1745–60 (1985).
A. H. Kahn, J. Res. National Bureau if Standards 89 47–54. (1984).
B. A. Auld, Theoretical Characterization and Comparison of Resonant Probe Microwave Eddy-Current Testing with Conventional Low Frequency Eddy-Current Methods, in Eddy-Current Characterization of Materials and Structures, ASTM STP 722, eds., G. Birnbaum and G. Free, ( American Society for Testing and Materials, Philadelphia, 1981 ), 332–347.
Nag Fortran Library MK 11, Numerical Algorithms Group, 256 Banbury Rd., Oxford, 0X2 7DE UK.
Induction by a current filament above a half-space is treated by many authors (e. g. J. A. Tegopoulos and E. E. Kriezis, “Eddy Currents in Linear Conducting Media. Studies in Electrical and Electronic Engineering 16” (Elsevier, Amsterdam, 1985), p. 89ff). Results for a coil of finite cross-section are obtained by superposition.
C. V. Dodd and W. E. Deeds, J. Appl. Phys. 39 2829–38 (1968)
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Burke, S.K. (1987). Eddy Current Induction by a Coil near a Conducting Edge in 2D. In: Thompson, D.O., Chimenti, D.E. (eds) Review of Progress in Quantitative Nondestructive Evaluation. Review of Progress in Quantitative Nondestructive Evaluation, vol 6 A. Springer, Boston, MA. https://doi.org/10.1007/978-1-4613-1893-4_19
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DOI: https://doi.org/10.1007/978-1-4613-1893-4_19
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