ZHANG Feiyang, YAN Feng, HUAN Zhengli, LOU Yue, MA Lizhi, XU Xuanyu
(China Electronics Technology Group Corporation NO. 46 Research Institute, Tianjin 300220, China)
Abstract: Ultra-high Curie temperature bismuth-layered lead-free piezoelectric ceramics based on Ca1-2x(NaCe)xBi2Nb2O9 (x=0, 0.025, 0.050, 0.075, 0.100, 0.150) were prepared by conventional solid state reaction method. The crystal structure and fracture morphology, as well as the dielectric, piezoelectric and ferroelectric properties, were characterized by XRD, SEM, EDS and related electrical performance testing system. The influence of different doping content of (NaCe) on the performance of ceramics was investigated. The results show that when the doping content of (NaCe) is 0.050, the sintering temperature is 1150 ℃, the grains of the ceramic present highly anisotropic plate-like shape and they are very dense. The piezoelectric constant is 17 pC/N. The dielectric loss is only 0.45% and the Curie temperature is 911 ℃. Meanwhile, the thermal stability of Ca0.9(NaCe)0.05Bi2Nb2O9 ceramic is also very outstanding, suggesting that the doped Ca0.9(NaCe)0.05Bi2Nb2O9 ceramic is a potential material in the field of high temperature and high frequency applications.
Key words: bismuth-layered lead-free piezoelectric ceramics; doped; piezoelectric property; thermal stability