Analytical solutions in eddy current testing of layered metals with continuous conductivity profiles

Author

Theodoulidis, T.P. ; Tsiboukis, T.D. ; Kriezis, E.E.

Author_Institution

Dept. of Electr. & Comput. Eng., Aristotelian Univ. of Thessaloniki, Greece

Volume

31

Issue

3

fYear

1995

fDate

5/1/1995 12:00:00 AM

Firstpage

2254

Lastpage

2260

Abstract

In this paper exact analytical expressions for the impedance of a cylindrical air-core coil above a layered metal structure whose conductivity varies continuously with depth are presented. Although the model is general, attention is focused on three conductivity profiles: the linear, the quadratic and the exponential. The derived expressions for the impedance change for each profile could provide a useful tool for the solution of the inverse problem: that of determining the conductivity from variable frequency measurements of the impedance. Furthermore, the obtained final formulas contain elegant mathematical functions and show a substantially higher computational efficiency with respect to existing methods

Keywords

coils; eddy current testing; electrical conductivity measurement; inverse problems; probes; computational efficiency; conductivity profiles; continuous conductivity profiles; cylindrical air-core coil; eddy current testing; exponential profile; impedance change; inverse problem; layered metals; linear profile; mathematical functions; quadratic profile; variable frequency measurements; Coils; Conductivity measurement; Current measurement; Differential equations; Eddy current testing; Eddy currents; Frequency measurement; Geometry; Inverse problems; Surface impedance;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.376236

Filename

376236