Detection of cracks by eddy current testing based on dilation invariance principle

Abstract

The objective of this paper is a proof of concept on the possibility to measure the same magnetic fields, by the principle of dilation invariance. According to this principle, dilation of the dimensional and electrical parameters of a probe and a plate with crack reproduces the same magnetic field (measured at every dilated point) which was produced by a probe and a plate with crack, without dilation. This implies that, in order to evaluate the performance of eddy current method in a specific industrial case study, one can carry out tests in a scaled model in the laboratory and then, extend the conclusions to the real situation by using dilation invariance principle. The experimental and simulation results show a good agreement of crack detection by using two eddy current probes of which one is the dilated version of the other.

Keywords

ECT eddy current testing nondestructive evaluation dilation invariance principle

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