A magnetic field optimized structure electromagnetic acoustic transducer design
In order to further enhance the detection capability of electromagnetic ultrasonic testing technology in the field of pipe thickness measurement,the structure of electromagnetic ultrasonic transducer(EMAT)is optimized in this paper.A multi-magnet symmetric distribution type EMAT is proposed,which can realize a smaller magnet volume to produce a stronger surface remanent magnetic strength.The influence of eddy currents on the measurement is solved by using slots on the surface of silicon steel to limit the area of eddy current formation.Establishment of thickness measurement experimental system,compared with a single magnet type and multi-magnet symmetric distribution type EMAT in different lifting distance on the change rule of the detection signal.The results show that multi-magnet symmetric distribution type structure can be enhanced through the EMAT bias field to achieve a better signal-to-noise ratio effect.The use of high-temperature resistant probe shell and samarium cobalt magnets improves the detection performance of EMAT probe in high temperature environment.
Electromagnetic ultrasonic transducerThickness measurementHigh temperature
万方数据
维普
