共查询到19条相似文献,搜索用时 921 毫秒
1.
研究了铌掺杂锆锡钛酸铅铁电陶瓷Pb0.99Nb0.02[(Zr0.90Sn0.10)0.96Ti0.04]0.98O3(PZST 90/10-4-2Nb)在静水压(0-300 MPa)下的电荷释放量和介电性能. 对压力诱导的低温铁电三方(FR(LT))→反铁电正交(AO)相变进行了研究. PZST 90/10-4-2Nb铁电陶瓷分为未极化、极化和压力去极化三种. 极化PZST 90/10-4-2Nb陶瓷FR(LT)→AO相变过程中,电荷释放量为29.3 μC/cm2,相变压力为140 MPa. 介电性能表明:极化PZST 90/10-4-2Nb陶瓷相变压力为136 MPa,而未极化陶瓷相变压力为104 MPa,压力去极化陶瓷未表现出明显的相变特征.
关键词:
静水压
铁电陶瓷
相变
介电 相似文献
2.
研究了Pb[(Zr052Ti048)095(Mn1/3Nb2/3)005]O3 (PMnN_PZT) 铁电陶瓷电滞回线的温度和频率响应,结果显示在高频和室温条件下测试铁电特性时,电滞回线呈现“束腰”形状,而不是通常所看到的方形回线 . 在低频和高温条件下测试时才能观察到正常的方形回线,同时,诸如矫顽场、极化强度、 内偏场这些重要的铁电参数也会随频率和温度发生显著的变化. 剩余极化强度随频率和温度 的大幅增长表明“束腰” 电滞回线有可能是由于缺陷偶极子引起的. 电滞回线形状与温度 和频率存在较强的相关性说明缺陷偶极子存在一特征弛豫时间,缺陷偶极子反转响应速度由 此弛豫时间决定.
关键词:
电滞回线
氧空位
频率响应
温度响应 相似文献
3.
用弱场介电温谱、热释电流谱、强场电滞回线和变温X射线衍射谱研究了微量La掺杂Pb(Zr,Sn,Ti)O3(PZST)反铁电(AFEt)陶瓷在-100—180℃温区内的结构与电学特性.弱场介电温谱显示,AFEt陶瓷在低温段(-100—50℃)呈现介电频率弥散(0.1—100kHz)和扩散型相变的特征,而变温X射线衍射谱却表明材料在这一温区内保持四方相结构;低温下经强场作用后,AFEt被诱导为亚稳三方铁电态,介电频率弥散消失.基于多元复杂化合物的组分起伏理论,讨论了PZST AFEt陶瓷
关键词:
Pb(Zr
Sn
3反铁电陶瓷')" href="#">Ti)O3反铁电陶瓷
反铁电弛豫
相变
变温X射线衍射 相似文献
4.
从Landau-Devonshire唯象理论出发,考虑到晶格失配导致的NFDA3位错应力场与极化场的耦合,研究了在SrTiO3衬底上外延生长的PbZr0.4Ti0.6O3薄膜厚度对其自发极化强度、电滞回线的影响. 结果表明,产生刃位错的PbZr0.4Ti0.6O3薄膜临界厚度为~1.27nm,当薄膜厚度大于临界厚度时,在所形成的位错附近,极化强度出现急剧变化,形成自发极化强度明显减弱的“死层”;随着薄膜厚度的减小,位错间距增大,“死层”厚度与薄膜总厚度之比增加. 由薄膜电滞回线的变化情况可知,其剩余极化强度随着薄膜厚度的减小而逐渐减小.
关键词:
铁电薄膜
自发极化强度
电滞回线
位错 相似文献
5.
用传统固相烧结法制备了Sr2Bi4-xDyxTi5 O18(SBDT-x, x=0—0.20)陶瓷样品. x射线衍射分析表明, 微量的Dy掺杂没有影 响Sr2Bi4Ti5O18(SBTi) 原有的层状钙钛 矿结构. 通过研究样品的介电特性, 发现Dy掺杂减小了材料的损耗因子, 降低了样品铁电- 顺电相转变的居里温度. 铁电性能测量结果表明, 随Dy含量的增加, SBDT-x系列样品的剩余 极化先增大, 后减小. 当Dy掺杂量为0.01时, 剩余极化达到最大值, 约为20.1 μC·cm-2. 掺杂引起剩余极化的变化, 与材料中缺陷浓度、内应力以及晶格畸变程度等因 素有关, 是多种作用机理相互竞争的结果. (Bi2O2)2+ 层通常被看作是绝缘层和空间电荷库, 对材料的铁电性能起关键作用. 掺杂离子进入(Bi2O2)2+层会导致铁电性能变差.
关键词:
2Bi4Ti5O18陶瓷')" href="#">Sr2Bi4Ti5O18陶瓷
Dy掺 杂
铁电性能
居里温度 相似文献
6.
7.
8.
9.
利用X射线衍射、弱场介电温度谱、强场极化强度研究了不同La含量(Pb1-xLa2x3)(Zr06Sn03Ti01)O3(000≤x≤012)(PLZSnT)陶瓷的相变与电学特性.实验发现,随La含量增大,室温下材料由铁电三方相(x=000)转变为反铁电四方相(003≤x≤009)和立方相(x=012).介电测试表明,La含量增大,反铁电→顺电相变温度降低,峰值介电常量减小.在x=006的PLZSnT三元相图中,反铁电四方相区扩大到Ti含量约为18at%,该系统反铁电陶瓷具有“窄、斜”型双电滞回线和“三电滞回线”;在高Zr、高Sn区,反铁电→顺电相变呈现弥散相变和介电频率色散特征,即反铁电极化弛豫现象.从ABO3钙钛矿结构的容忍因子(t)和反铁电相的结构特征出发,讨论了La对Pb(Zr,Sn,Ti)O3相变与电学性质的影响机理
关键词:
场诱相变
弛豫型反铁电体
介电性能
La调节Pb(Zr
Sn
Ti)O3 相似文献
10.
《物理学报》2020,(12)
在实际应用中,反铁电陶瓷常处于快速变化的脉冲电场下,而传统电滞回线测量时所施加的电场变化速率较慢,并不能真实反映反铁电陶瓷实际应用时的极化和相变行为.本研究建立了反铁电陶瓷脉冲电滞回线测试平台,研究了Pb_(0.94)La_(0.04)[(Zr_(0.52)Sn_(0.48))_(0.84)Ti_(0.16)]O_3反铁电陶瓷在微秒级脉冲电场下的极化和相变行为.研究结果表明,反铁电陶瓷在微秒级脉冲电场下可以发生相变,但其极化强度降低,正向相变电场变高,反向相变电场变低,从而导致其储能特性发生了显著的变化.因此,低频电滞回线并不能真实反映反铁电陶瓷在脉冲电场下的性能,脉冲电滞回线对其应用具有更重要的参考价值. 相似文献
11.
R. Yimnirun X. Tan S. Ananta S. Wongsaenmai 《Applied Physics A: Materials Science & Processing》2007,88(2):323-328
In this study, lead indium niobate (Pb(In1/2Nb1/2)O3 or PIN) ceramics were prepared by a wolframite precursor method via a vibro-milling technique. Fine-grain ceramics were achieved
with average grain size of 1–2 μm, indicating advantage of the vibro-milling technique used. The dielectric and ferroelectric
properties were measured by means of an automated dielectric measurement set-up and a standardized ferroelectric tester, respectively.
The dielectric properties of PIN ceramic were measured as functions of both temperature and frequency. The results indicated
that the dielectric properties of the PIN ceramic were of relaxor ferroelectric behavior with temperature of dielectric maximum
(Tm)∼53 °C and dielectric constant (εr)∼4300 (at 1 kHz). The P–E hysteresis loop measurements at various temperatures showed that the ferroelectric properties of
the PIN ceramic changed from the paraelectric behavior at temperature above Tm to slim-loop type relaxor behavior at temperature slightly below Tm. Moreover, the P–E loop became more open at temperatures much lower than Tm.
PACS 77.22.Ch; 77.84.Dy 相似文献
12.
Hyun Woo Chung 《Applied Surface Science》2006,252(13):4545-4548
New ferroelectric Pb(Zr,Ti)O3-Pb(Mn,W,Sb,Nb)O3 (PZT-PMWSN) thin film has been deposited on a Pt/Ti/SiO2/Si substrate by pulsed laser deposition. Buffer layer was adopted between film and substrate to improve the ferroelectric properties of PZT-PMWSN films. Effect of a Pb(Zr0.52Ti0.48)O3 (PZT) and (Pb0.72La0.28)Ti0.93O3 (PLT) buffer layers on the stabilization of perovskite phase and the suppression of pyrochlore phase has been examined. Role of buffer layers was investigated depending on different types of buffer layer and thickness. The PZT-PMWSN thin films with buffer layer have higher remnant polarization and switching polarization values by suppressing pyrochlore phase formation. The remnant polarization, saturation polarization, coercive field and relative dielectric constant of 10-nm-thick PLT buffered PZT-PMWSN thin film with no pyrochlore phase were observed to be about 18.523 μC/cm2, 47.538 μC/cm2, 63.901 kV/cm and 854, respectively. 相似文献
13.
M. Chandrasekhar 《Phase Transitions》2016,89(9):944-957
Dielectric, ferroelectric and piezoelectric properties of the (0.94–x) Bi0.5Na0.5TiO3–0.06BaTiO3–xK0.5Na0.5NbO3/BNT–BT–KNN ceramics with x = 0.02 and 0.05 (2KNN and 5KNN) were studied in detail. Dielectric study and temperature-dependent polarization hysteresis loops indicated a ferroelectric-to-antiferroelectric transition at depolarization temperature (Td). The low Td in both the ceramic samples suggested the dominant antiferroelectric ordering at room temperature (RT), which was also confirmed by RT polarization and strain hysteresis loops studies. Antiferroelectric-to-paraelectric phase transition temperature (Tm) was nearly same for both systems. The 5KNN ceramic samples showed the relaxor behaviour. The values of the dielectric constant, Td, and maximum strain percentage increased, whereas the coercive field and remnant polarization decreased with the increase of the KNN percentage in the BNT–BT–KNN system. High-energy storage density ~0.5 J/cm3 at RT hinted about the suitability of the 5KNN system for energy storage applications. 相似文献
14.
Polycrystalline ceramics of the perovskite solid solution 0.5Pb(Ni1/3Nb2/3)O3-(0.5-x)-Pb(Zn1/3Nb2/3)O3–xPb(Zr1/2Ti1/2)O3; x=0.0–0.5 (PNN–PZN–PZT) were synthesized by a modified columbite method. Highly dense ceramics lacking parasitic pyrochlore
phases were prepared at a calcination temperature of 950 °C by using a double-crucible configuration, excess PbO (2 mol %),
and a fast heating/cooling rate (20 °C/min). The ceramics were characterized by a variety of techniques including X-ray diffraction,
ferroelectric hysteresis loop measurements, field-induced longitudinal strain measurements, and electron microscopy. It was
observed that the remanent polarization exhibited a significant increase with increasing x. In addition, the squareness of
the hysteresis loop increased quasi-linearly as the molar fraction of PZT increased. The maximum spontaneous polarization
and remanent polarization for the x=0.5 composition were 31.9 μC/cm2 and 25.2 μC/cm2, respectively. Moreover, the data were analyzed to show the evolution of the micro-domain state as a function of the molar
fraction of PZT.
PACS 77.22.-d; 77.80.Bh; 77.84.Dy; 61.10.Nz; 77.80.Dj 相似文献
15.
V. G. Beshenkov V. A. Marchenko A. G. Znamenskii 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2010,4(5):761-765
The composition of PZT thin films deposited by diode HF sputtering of a ceramic target on Pt/Ti/SiO2/Si substrates was studied. The remanent polarization of grown films was to 22 μC/cm2. A technique for verifying the adequacy of elemental and phase composition of thin films to the ferroelectric phase composition was proposed. The problems of reliable contact of Pt electrodes with the PZT layer were considered. 相似文献
16.
《Current Applied Physics》2019,19(12):1383-1390
To investigate the effect of indium-tin-oxide (ITO) electrode on the Al-doped HfO2 (Al:HfO2) ferroelectric thin films, we fabricated and characterized the ITO/Al:HfO2/ITO and ITO/Al:HfO2/TiN capacitors by changing the annealing conditions. The ferroelectric remnant polarization (2Pr) was obtained to be 13.25 μC/cm2 for the ITO/Al:HfO2/TiN capacitors with the post-deposition annealing, which was termed T1. The 2Pr decreased after the post-metallization annealing due to the interface degradation between the Al:HfO2 and ITO electrode. Alternatively, the switching time and activation field of the T1 for the ferroelectric polarization switching were 1.25 μs and 1.15 MV/cm. These parameters were sensitively influenced by the interfacial dead layer formation and the amounts of ferroelectric orthorhombic phase. Furthermore, the fatigue endurance of the T1 were improved by preventing the crowding of oxygen vacancies at interfaces between the Al:HfO2 and top electrodes, in which the polarization values did not experience marked variations even after the fatigue cycles of 108. 相似文献
17.
《Current Applied Physics》2019,19(9):1040-1045
Normal-ferroelectric Pb(Zr0.52Ti0.48)O3 (PZT) and relaxor-ferroelectric Pb0.9La0.1(Zr0.52Ti0.48)O3 (PLZT) thin-films are deposited on SrRuO3-covered SrTiO3/Si substrates. An ultrahigh recoverable energy-storage density (Ureco) of 68.2 J/cm3 and energy efficiency (η) of 80.4% are achieved in the PLZT thin-films under a large breakdown strength (EBD) of 3600 kV/cm. These values are much lower in the PZT thin-films (Ureco of 10.3 J/cm3 and η of 62.4% at EBD of 1000 kV/cm). In addition, the remanent polarization (Pr) and dielectric-constant are also investigated to evaluate the breakdown strength in thin-films. Polar nano-regions (PNRs) are created in the PLZT thin-films to enable relaxor behavior and lead to slim polarization loops along with very small Pr. The excellent operating temperature of energy-storage performance and also the breakdown strength obtained in the PLZT thin-films are mainly ascribed to the presence of PNRs. Moreover, both PZT and PLZT thin-films exhibit superior performance up to 1010 times of charge-discharge cycling. 相似文献
18.
Electromechanical-induced antiferroelectricben ferroelectric phase transition in PbLa(Zr,Sn,Ti)O3 ceramic 下载免费PDF全文
Antiferroelectric—ferroelectric (AFE—FE) phase transition in ceramic Pb0.97La0.02(Zr0.75Sn0.136Ti0.114)O3 (PLZST) was studied by dielectric spectroscopy as functions of frequency (102—105 Hz) and pressure (0—500 MPa) under a DC electric field. The hydrostatic pressure-dependent remnant polarization and dielectric constant were measured. The results show that remnant polarization of the metastable rhombohedral ferroelectric PLZST poled ceramic decreases sharply and depoles completely at phase transition under hydrostatic pressure. The dielectric constant undergoes an abrupt jump twice during a load and unload cycle under an electric field. The two abrupt jumps correspond to two phase transitions, FE—AFE and AFE—FE. 相似文献
19.
Yu -Jin Chang 《Applied Physics A: Materials Science & Processing》1982,29(4):237-244
95/5 PZT ceramics with compositions of Pb(Zr1–x
Ti
x
)3+1 wt% Nb2O5 (x=0.025 and 0.04) are studied with TEM. The coexistence of both ferroelectric (F) and antiferroelectric (AF) phases in one ceramic grain at room temperature is confirmed for these two compositions. The AF phase is mainly tetragonal, while a pseudo-cubic arrangement of AF polarization is also possibly present. When the Ti4+ concentration is increased, the F phase becomes predominant. Direct interfaces between F and AF domains can be observed, the former expands at the expense of the latter when bombarded by 200 keV electrons. 相似文献