Numerical Simulation Of Electromagnetic Acoustic Transducer Used For Nondestructive Testing

The electromagnetic acoustic transducer (EMAT) is a new ultrasonic transmitting and receiving device. As no contact is required between the transducer and the test piece, the EMAT has extend traditional ultrasonic application into high-temperature, high-speed and on-line detection fields. In addition, without the necessity of a good surface condition, the time consuming and complicated preparation works of the test piece also can be omitted, and thus lead to a great improvement of the detection efficiency. However, the EMAT has the problem of low energy conversion, its principle should be studied and parameters should be optimized to improve the energy conversion rate. Because the EMAT's nonlinear problems and electromagnetic– stress field coupling problem is very complex, it is difficult to analysis the EMAT's principle using traditional analytical methods, thus this paper gives a EMAT's mathematical model which is established on the basis of the EMAT's mathematical equations, then models and simulates it by means of finite element methods. And also several major parameters of the EMAT are analysed, the law of every parameter impacted on the EMAT has obtained.