Accurate Modeling and Analysis for Transmission Process of Surface Wave EMATs

To increase the accuracy of the model of the meander-line-coil surface wave EMATs used for the inspection of surface layer of aluminum plates, this paper established a novel 3D accurate model by combining numerical calculations and analytical solutions with special attention to the influence of the dynamic magnetic field. Simulation and analysis indicated that the frequency of the surface waves due to the dynamic magnetic field was twice of that due to the static magnetic field; the double-frequency surface wave component could effectively improve the sensitivity of the transducers; both increasing transmitting current and decreasing lift-off distance could significantly enhance the component. The validity and accuracy of the established model was verified by experiment.