Study And Development Of Re Giant Magnetostrictive Transducer And Software Package Of Optimization Design

The ultrasonic emission source in the widely used ultrasonic nondestructive testing device now is piezoelectric ceramic.Its radialization power is low and penetrating capability is not good,so it doesn't meet the testing requirement of mass component in the large bridge(such as bridge tower,pier,girder). However giant magnetostrictiv material has many advantages,like high radialization power,short aftershock,long transmiting distance,low work voltage,small volumes and so on.By researching and analysing the idiosyncrasy and design method of the prevalent Giant Magnetostrictiy Transducer, a suit of software package has been empoldered which can optimize the transducer.The rare earth transducer which has high power and good performance has been made by using of the new software package.This kind of transducer is suitable for nondestructive testing of bridge.Using this transducer ,the nondestructive testing device can measure the transmit velocity of ultrasonic in the load(such as concrete) accvrately.And hence the ultrasonic nondestructive testing about quality of bridge and mass concrete inside has been realized.The new software package is empoldered by using of Four-terminal Network Method and Fourier transform.The GMM transducer has been calculated and analysed by it.The software package can give the result by data and curve after inputing some structure and material parameters of the transducer. It can also optimize the transducer. It can optimize the pre pressure,electrical structure and geometrical structure of the transducer and hence a reliable design theory is poromoted for the transducer.The distribution of magnetic field of the GMM transducer has been calculated by using of Finite Element Method (FEM).The result is the same as that derived from software package .This validates that the software package is effective. The impedance of the transducer under small signal and the waveform of the ultrasonic under big electricity have been measured.Comparing the result with that derived from the software package,it proved that the result which was produced by software package was right. At last ,GMM transducer with high power has been developed by using the software package. It is suitable for nondestructive testing of bridge.The transmiting power of the transducer is more than 10kw,and the transmiting signal is close to mono-pulse.The main frequency of the transducer is 43kHz and aftershock is very short.