Optimal Design of Electromagnetic Acoustic Transducer

This paper considers the design of EMAT （Electro-Magnetic Acoustic Transducer） based on numerical simulation. The EMAT consists of an exiting coil and two permanent magnets, which transmits the ultrasonic wave by the Lorentz force between the eddy current and the static magnetic field by the magnets. From the experimental result on self-prepared EMATs, the intensity and the directivity of the transmitted wave depend on the widths of the coil and the magnets. By means of EEM analysis the authors attempt to determine the optimal values of the above widths such that both the intensity and the directivity achieve the maximum or allowable performance.