A new pulse electromagnet structure to model a transverse magnetic field to pick up the out-of-plane for laser-EMAT integrated system

In order for an electromagnetic acoustic transducer (EMAT) to be able pick up the out-of-plane vibrations of ultrasonic waves generated by laser and facilitate movement system, a new pulse electromagnet EMAT is proposed, which can combined with form laser–pulse integrated system. Because unique structure EMAT, it not only generate uniform transverse magnetic field in shallow surface specimen just below receiving coil but also leave enough space above ensure smooth radiation source on specimen. The optimal parameters probe are determined combining finite element simulation model orthogonal analysis method. experimental results show that pulsed at least 0.22 T when each C-electromagnet, respectively, injects 20 A. used receive various modes vibration velocity component. It lays foundation research simultaneous detection railhead internal defects using system through one scan.