A new frequency-tuned longitudinal wave transducer for nondestructive inspection of pipes based on magnetostrictive effect

Facing the difficulty of carrying out optimum inspection of defects and optimization design of Kwun´s magnetostrictive transducer, a new transducer configuration is proposed. The mutilple-belts coils are used as the transmitting coil and receiving coil. This kind of coil is often used in electromagnetic ultrasonic transducer (EMAT), but it is used for magnetostrictive tansducer firstly. To verify the performance of the transducer, several experiments were performed. The results show that the proposed coils not only could tune the center frequency but also could improve the amplitude and signal-to-noise (SNR) of the detected signals.