PMN-PT detector for electron acoustic imaging system

摘要

The relaxor-based ferroelectric single crystal 67Pb(Mg/sub 1/3/Nb/sub 2/3/)O/sub 3/-33PbTiO/sub 3/ (PMN-PT) with size of /spl Phi/ 40/spl times/80 mm have been grown by a modified Bridgman method in our lab. Their typical properties are d/sub 33//spl sim/1800 pc/N, K/sub 33//spl sim/0.92 and /spl epsi//sub 33//sup T/spl sim//4200. The crystal is used for designing electron acoustic signal detector in the Electron Acoustic Imaging System (EAIS) which is a new non-destructive technology for microstructure analysis, defects testing beneath the surface and properties study on micro-region. The amplitude of electron acoustic signal detected by PMN-PT detector is twice as high as that of PZT-type detector. The resolution of electron acoustic image is clearly improving. For comparison, the electron acoustic images of ferroelectric domain, stress distribution of aluminum and PZN-PZ-PT ceramic texture were presented using PMN-PT detector and PZT-type detector, respectively. The results show that PMN-PT crystal is particularly useful as a receiving detector in the electron acoustic imaging system and other ultrasonic imaging systems.