Optimal design of surface wave emats for enhancing their ultrasonic signal strength

The strength of the ultrasonic signal transmitted by electromagnetic acoustic transducers (EMATs) is very weak, which severely confines the further expansion of the application scope of EMATs. To solve this problem, the features of the transmission process of a surface wave EMAT are studied based on a 3-D model. Simulation reveals that performances of the transducer are significantly affected by its parameters. Aiming at enhancing the strength of the ultrasonic signal, this paper investigates the influence of EMAT parameters on the ultrasound field of the transducer and accomplishes the optimal design of the EMAT by utilizing orthogonal test method. Experiments indicate that after optimization, the received signal of the EMAT has increased by 162.3%, which suggests the ultrasonic signal of EMATs can be effectively enhanced by utilizing orthogonal test method based on the 3-D EMAT model. Acknoweledgement: Supported by “the Fundamental Research Funds for Central Universities” (Grant No. HIT. NSRIF. 2012008)