脉冲电容器用细电滞回线铁电陶瓷材料的研究

采用低锆区的Pb(Zr_0.42Sn_0.40Ti_0.18)O₃(PZST42/40/18)铁电陶瓷为基, 通过少量La和Ba取代Pb同时Nb取代(Zr, Sn, Ti)复合取代的方法得到掺杂PZST42/40/18细电滞回线铁电陶瓷, 其最大极化强度P_max≈20.66μC/cm², 剩余极化强度P_r≈0.55μC/cm^{关键词： 细电滞回线 铁电陶瓷 PZST 脉冲电容器}

Study on slim-loop ferroelectric ceramics for high-power pulse capacitors

A slim-loop ferroelectric ceramic of Pb (Zr_0.42Sn_0.40Ti_0.18)O₃(PZST42/40/18) was prepared by partially replacing Pb with Ba and La, and replacing (Zr, Sn, Ti) with Nb in low zirconiumn. The saturation polarization (P_s), the remnant polarization (P_r) and the area of the hysteresis loop (S) were measured to be 20.66 μC/cm², 0.55 μC/cm² and 0.0298J/cm³, respectively. Relative permittivity (ε)≈2840 can be reached in this ferroelectric ceramic at room temperature and frequency of 1kHz, but the energy density (w) is 0.319J/cm³. The results of the pulse charge-discharge measurements showed that a single piece of the PZST42/40/18 slim-loop ferroelectric ceramic can carry 2330 A and endures charge-discharge cycle over one thousand times. The released charge decreases with increasing cycle times according to second order exponential decay. These ferroelectric ceramics have potential for pulsed power capacitor applications.