Numerical and experimental evaluation of the receiving performance of meander-line coil EMATs

Electromagnetic acoustic transducers (EMATs) have low transduction efficiency and they are sensitive to the electromagnetic noise, which can result in low signal-to-noise ratio of the received signals. This article presents a multi-physical finite element (FE) model for meander-line (ML) coil EMATs, operating on the Lorentz force mechanism, and the influence of the surrounding electromagnetic fields is also taken into consideration. The generation and reception of Rayleigh waves by EMATs can be described by this model. The receiving performances of two kinds of ML coils have been simulated by the FE model and tested by experiments. The experimental results agree well with the simulation.

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