Field Induced Phase Transition Behavior And Energy Storage Characteristics Of Antiferroelectric Ceramics Based On PLZST

In recent years,pulsed power equipment such as electron guns,particle beam accelerators,ballistic missile systems and high-power microwave sources can be developed and applied with the rapid development of pulsed power technology.As an important part of the pulse power system,energy storage components have been limiting the development of pulse power equipment.Therefore,how to achieve the characteristics of high energy storage,high power and rapid charge-discharge of energy storage materials has become an urgent problem for academia and industry.In this experiment,the intrinsic material properties of PLZST-based anti-ferroelectric ceramics were modified by means of composite,doping and proportioning.In addition,the influence of the two types of forming samples and the thickness of thick film by isostatic treatment on the energy storage characteristics were researched.The purpose of this study is to optimize the energy storage and dielectric properties of PLZST-based anti-ferroelectric ceramics through different research methods,so as to provide a new way for the further research of PLZST-based anti-ferroelectric ceramics.The results are as follows:?1?The influence of Zr:Sn ratio on the energy storage characteristics of PBLZST ceramics was studied.The experimental results showed that the increase of Sn⁴⁺content promotes grain refinement and contributed to the stability of anti-ferroelectric phase,which improve PBLZST ceramic phase transition and dielectric breakdown strength.Therefore,the maximum effective energy storage density of 1.94 J/cm³.In addition,the small amount of Ba²⁺doping and the increase of Sn⁴⁺have a stability effect on the anti-ferroelectric phase,so that the ceramics have a high energy storage efficiency and the max value more than 80%.These performances demonstrate the potential of the PBLZST materials for pulse energy storage components.?2?The two-phase composite of PLZST ceramics with high polarization tetragonal PLZST and high phase transition field strength is used to achieve the complementary advantages of two phase structure ceramics,so as to improve the energy storage characteristics.In addition,the influence of membrane thickness and sample type?block,thick film?on energy storage characteristics has been studied.The results show that the thick film samples often show more excellent and stable energy storage characteristics compared with the block material.The strength of phase transition field of tetragonal phase PLZST ceramics was significantly enhanced by the composition of orthogonal phase PLZST ceramics.For four layers of thick film,the maximum effective energy storage density W_re is 3.18 J/cm³.The two layers of thick film has higher breakdown strength due to the reduction of defects and the maximum effective energy storage density W_re is 3.44 J/cm³.?3?As a quantum parametric material,SrTiO₃ has a high dielectric constant?>300?,breakdown strength and high energy storage efficiency.PLZST-based anti-ferroelectric material and SrTiO₃ are combined and doped to achieve high energy storage efficiency.The results show that the increase of SrTiO₃ composite quantity promotes the transition trend of anti-ferroelectric phase to relaxation anti-ferroelectric phase in the hysteresis loop of composite ceramics at room temperature and the energy storage efficiency is significantly improved.The maximum effective energy storage density is 1.6 J/cm³ and the energy storage efficiency is 83.85%when the composite quantity is 0.05.In addition,the performance of the composite method is better than that of the doped method when the amount of SrTiO₃ is the same.