Growth and Electric Properties of Relaxor Ferroelectric Single Crystal PZNT93/7

Relaxor ferroelectric single crystal Pb[(Zn1/3Nb2/3)0.93Ti0.07]O3 (PZNT93/7) was grown by a flux-Bridgman method using 50mol% PbO as the flux. Nucleation was modified by O2 gas cooling system at the bottom of Pt crucible. The size of the crucible was 40mm × 40mm × 300mm. The rate of pulling-down was 0.5mm/h and the rate of oxygen fluid was 1-1.6L/min. The maximum size of the obtained crystals was φ30mm×25mm. The as-grown PZNT crystal exhibits an obvious growth morphology and the largest revealed face is (001) determined by X-ray diffraction. Due to unstability of O2 fluid and slow mass transport, red PbO inclusions are easily formed in the crystal. The measurements of dielectric and ferroelectric properties show that the crystal can satisfy the requirements of array-type transducers in a new type of medical diagnostic equipment.