where expertise comes together - since 1996 -

The Largest Open Access Portal of Nondestructive Testing (NDT)

Conference Proceedings, Articles, News, Exhibition, Forum, Network and more

where expertise comes together
- since 1996 -

Technical Discussions
06:24 Apr-16-2004
determining conductivity using eddy current testing

Hi, I have a question about measuring conductivity using an eddy current device. I obtained results from several unknown samples using an eddy current tester which simply displays an impedance diagram. I've also applied the eddy current tester to some samples of known conductivity, so I have some calibration points on my impedance display. All my measurements were done at the knee of the impedance plot, where mostly the imaginary component varies. Now I would like to find the conductivity of the unknown samples, by measuring their location on the impedance plot and comparing that result to the location of the calibration samples. However in order to get the conductivity of the unknown samples, I need a function relating the position of a sample on the locus to its conductivity. This function should partially be based on the experimental calibration data, however the form of this function should be based on some underlying physical theory, whether it's an equivalent circuit model or the EM equations underlying the eddy current test.

That is I need to know if the graph of location on the locus vs. conductivity for the calibration points should follow a polynomial of a certain order, or 1/(r^2-1) or what. If I had enough calibration point is could just fit some polynomial to them, but I don't, so I need to base it on the underlying theory. Any suggestions on how to do this, whether using physical theory or equivalent circuit?

Thank you.


Product Spotlight

Research and Applications Development For NDT

The Research and Applications Development (RAD) group is a newly formed team within Acuren dedicat
ed to tackling challenging inspection problems. Our focus is the development of novel, field deployable, advanced inspection techniques for use in cases where standard NDT methods are ineffective. We don't wait for new innovations, we engineer them. From concept to commissioning.

Swift & Scorpion2 - a state-of-the-art remote-control ultrasonic crawler

The Swift and Scorpion2 dry-coupled, remote-access ultrasonic crawler bring major efficiency and d
ata improvements to tank shell inspections and other structures such as vessels and offshore installations.


Very Powerful Superior Performance Extremely Portable Smart Phased Array Ultrasonic Flaw Detector an
d Recorder with 2 Conventional UT and TOFD Channels uniquely combines PA, single- and multi-channel conventional UT, and TOFD modalities providing 100% raw data recording and imaging. Suitable for all kinds of every-day ultrasonic inspections

Ultrasonic Testing Immersion Tanks with Unmatched Scanning Features

TecScan’s non-destructive testing Ultrasonic Immersion Tanks & scanners are designed for high perf
ormance and demanding NDT testing applications. Our Scan3D™ line of High Precision Immersion Tanks are specifically designed for automated ultrasonic testing of complex composites parts used in aerospace and industrial applications.

We use technical and analytics cookies to ensure that we will give you the best experience of our website - More Info
this is debug window