| ABSTRACT: |
SIMULTANEOUS MEASUREMENT OF MATERIAL PROPERTIES AND THICKNESS OF
CARBON STEEL PLATES USING PULSED EDDY CURRENTS
V.O. de Haan 1, and P. de Jong2
1 BonPhysics BV, Puttershoek, The Netherlands, 2 RTD BV, Rotterdam, The Netherlands.
It is well known from literature that Pulsed Eddy Currents generated by switching off a stationary current
through a coil above a carbon steel plate can be used to measure the thickness of the plate. The procedure is
to measure the induction voltage signal of a receiving coil for a known reference thickness and compare this
to the signal from an unknown thickness. The disadvantage of this method is that a reference measurement is
needed and the result is influenced by variations in material properties. The authors present a method using
the same technique but a different signal interpretation method, enabling the simultaneous determination of
material properties and thickness. A description of the signal interpretation method is given. It is shown that
for several types of carbon steel accuracy up to 10% in can be achieved.
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