Time Domain Analysis of Ultrasonic Wave Propagation Using an Electromagnetic Acoustic Transducer

In this paper an Electromagnetic Acoustic Transducer (EMAT) transmitter and receiver system is modelled. This work uses finite element as the numerical method to efficiently calculate the EMAT model. The model is capable of solving the transmitting and receiving of ultrasonic waves in non ferromagnetic materials. The EMAT model accounts for the coupling of electromagnetic analysis, mechanical analysis and acoustic analysis. The Finite element method used was thoroughly investigated by varying the mesh density and time step for convergence test and the EMAT parameters such as Rayleigh damping were also investigated to efficiently produce accurate results. The presented model also accounts for the calculation of induced voltage at the receiving EMAT by converting the transient particle displacement field in the aluminium material, and a shear stress analysis was conducted at different depths in the material.