物理学报2017，Vol.66Issue(4)：256-262,7.DOI:10.7498/aps.66.047201
冲击波作用下Pb(Zr0.95Ti0.05)O3铁电陶瓷去极化后电阻率动态特性
Dynamic resistivity of Pb(Zr0.95Ti0.05)O3 depolarized ferro electric under shock wave compression
摘要
Abstract
Explosive-driven ferroelectric generator (EDFEG) has important applications due to its excellent properties of high energy density and small volume. The output of EDFEG is based on the depolarization of ferroelectric during shock wave compression. In a "normal mode" configuration, a planar shock wave propagates in a direction perpendicular to the polarization axis. If the resulting depolarizing current passes through a large resistive load or a small capacitive load, high electric fields can be produced within the ferroelectric sample. In this case, a portion of the depolarizing charges are lost in the sample due to finite resistivity of shocked ferroelectrics during shock wave transit. But it is very difficult to accurately measure the resistivity of shocked ferroelectric during shock wave compression, due to high pressure and short duration time. In previous studies, the value of the resistivity of shocked Pb(Zr0.95Ti0.05)O3 (PZT95/5) ferroelectric was obtained from the experimental output charge difference for different large resistive loads or by fitting the experimental current histories. However, the current leakage was not observed directly in experiment in the past. Furthermore, the value of the resistivity obtained in each of all these studies was a time-averaged value. In the present work, a new experiment method is developed to investigate dynamic resistivity of PZT95/5 under shock wave compression, in which a pulse capacitor is used as an output load. The current leakage in shocked PZT95/5 is observed in the experiment at a shock stress of 3.5 GPa after the depolarization of all ferroelectrics. This current leakage is just related to the resistance of shocked PZT95/5 and the voltage applied. The experimental results show that the resistivity of shocked PZT95/5 continuously changes in a range of 2.2 × 104 ?·cm–3.5 × 104 ?·cm for time more than the shock transit time of the sample. Based on the experimental results, a dynamic resistance model is established to analyze the resistivity of depolarized PZT95/5 ferroelectric ceramic during shock wave transit in ferroelectric. The simulation results reveal dynamic characteristic of the resistivity of depolarized PZT95/5 ferroelectric ceramic under shock wave compression. The further analysis of experimental results shows that the resistivity continuously changes between 2.0 × 104 ?·cm and 8.0 × 104 ?·cm during shock transit in ferroelectrics. It is believed that dynamic characteristic of the resistivity of shocked PZT95/5 ferroelectric ceramic is related to pressure, electrical field applied and the defects in the material. The dynamic resistivity of shocked PZT95/5 obtained in this paper and its dynamic resistance model will be helpful for designing EDFEGs and their applications in the future.关键词
Pb(Zr0.95Ti0.05)O3/冲击波/去极化/电阻率Key words
Pb(Zr0.95Ti0.05)O3/shock wave/depolarization/resistivity引用本文复制引用
伍友成,刘高旻,戴文峰,高志鹏,贺红亮,郝世荣,邓建军..冲击波作用下Pb(Zr0.95Ti0.05)O3铁电陶瓷去极化后电阻率动态特性[J].物理学报,2017,66(4):256-262,7.基金项目
Project supported by the National High Technology Research and Development Program of China (Grant No. 2014AAX0X3029). 国家高技术研究发展计划(批准号: 2014AAX0X3029)资助的课题. （Grant No. 2014AAX0X3029）
