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1.
The pressure-driven force-electric conversion materials with extremely rapid response time have been widely used in mining, defense, and energy areas. The discharge process by the force-electric conversion effect in ferroelectrics is dominated by polar-nonpolar phase transformation. In this work, (Pb0.985La0.01)(ZrxTi1-x)O3 (PLZT, x = 0.85–0.94) ceramics is designed by tunning Zr4+/Ti4+ ratio and aliovalent La doping to achieve high remnant polarization (Pr) and excellent temperature stability. We focus on the pressure-driven depolarization in PLZT ceramics, and their corresponding phase structure, ferroelectric properties, dielectric properties, and thermal depolarization. In PLZT (x = 0.93) ceramics, the original polarization P0 increases to 43.42 μC/cm2. The pressure-driven depolarization releases 37.66 μC/cm2 with the depolarization proportion of 86.73%, which is attributed to irreversible ferroelectric-antiferroelectric phase transition. It also exhibits excellent temperature stability up to 120°C (> 36 μC/cm2). This work provides a high-performance alternative to Pb(Zr0.95Ti0.05)O3 and guidance for the development of pulse power energy conversion devices.  相似文献   

2.
Phase transitions and field-induced preferred orientation in (Pb1-xLax)(Zr0.90Ti0.10)1–x/4O3 (PLZT x/90/10) ceramics upon electric field cycling using in situ X-ray diffraction were studied. The evolution of the {200}pc and {111}pc diffraction line profiles indicate that PLZT 4/90/10 and PLZT 3/90/10 compositions undergo an antiferroelectric (AFE)–ferroelectric (FE) phase switching. Both PLZT 4/90/10 and PLZT 3/90/10 exhibit irreversible preferred orientation after experiencing the field-induced AFE-to-FE phase switching. An electric field-induced structure develops in both compositions which has a reversible character during the field decreasing in PLZT 4/90/10 and an irreversible character in PLZT 3/90/10. In addition, structural analysis of pre-poled PLZT 3/90/10 ceramics show that it is possible to induce consecutive FE-to-AFE and AFE-to-FE transitions when fields of reversed polarity are applied in sequence. The field range required to induce the AFE phase is broad, and the phase transition is kinetically slow. This kind of transition has rarely been reported before.  相似文献   

3.
Currently, there is an urgent need of extraordinary comprehensive pyroelectric materials for the wide application in detectors and energy harvesters. In this study, the (Pb1–1.5xLax)(Zr0.86Ti0.14)O3 (abbreviated as PLZT, x?=?0.02, 0.03, 0.04 and 0.05) ceramics located in ferroelectric-antiferroelectric (FE-AFE) phase boundary were designed and synthesized by using conventional solid-state reaction method. The microstructures, phase structures, dielectric, ferroelectric, thermal depolarization and pyroelectric properties of the PLZT ceramics with different La content were investigated thoroughly. The XRD results show that the PLZT ceramics change from FE phase to AFE phase with increasing La content. The significant improvement of pyroelectric coefficient p and figures of merit (FOMs) are achieved in the PLZT ceramics with the increase in La content because of the increased metastable ferroelectric phase under the application of electric field. The (Pb0.955La0.03)(Zr0.86Ti0.14)O3 (x?=?0.03) ceramic exhibits not only high p of 5.2×10?8C/cm2K and high depolarization temperature (Td) of 179?℃ but also excellent FOMs with Fi=2.2×10?10m/V, Fv=5.0×10?2m2/C, and Fd=3.47×10?5Pa?1/2. In addition, the highest p of 6.8×10?8C/cm2K is achieved in (Pb0.94La0.04)(Zr0.86Ti0.14)O3 (x?=?0.04) ceramic. These results demonstrate that the PLZT ceramics of x?=?0.03 and 0.04 are promising candidates for pyroelectric applications.  相似文献   

4.
Relaxor ferroelectrics are attracting an increasing interest in the application of pulse power systems due to their excellent energy storage performance. In this paper, the (1-x)(Ba0·85Ca0.15)(Zr0·1Ti0.9)O3-xBi(Mg0·5Ti0.5)O3 ((1-x)BCZT-xBMT, x ≤ 0.2) relaxor ceramics are prepared by the solid state method. The influence of BMT on the microstructure, dielectric and energy storage properties of the prepared ceramics is investigated. The XRD results show that the peak intensity of impurities (Bi2O3, TiO2 and Ba2Bi4Ti5O18) is gradually stronger than that of BCZT phase with x increasing. Meanwhile, the grain size of (1-x)BCZT-xBMT ceramics gradually increases on account of the appearance of impurities Bi2O3. Influenced by the impurities and BMT, the dielectric constant of prepared ceramics gradually decreases with x increasing. A large Wrec value of 0.65 J/cm3 with an ultrahigh η value of 97.89% is achieved at x = 0.15 due to the high breakdown strength and slim P-E hysteresis loop. Meanwhile, the η is insensitive to the electric field. The ultrahigh η leads to lesser energy loss during the charge and discharge process. It makes the 0.85BCZT-0.15BMT ceramic more attractive in the application of pulse power systems.  相似文献   

5.
Antiferroelectric (AFE) ceramics based on Pb(Zr,Sn,Ti)O3 (PZST) have shown great potential for applications in pulsed power capacitors because of their fast charge-discharge rates (on the order of nanoseconds). However, to date, it has been proven very difficult to simultaneously obtain large recoverable energy densities Wre and high energy efficiencies η in one type of ceramic, which limits the range of applications of these materials. Addressing this problem requires the development of ceramic materials that simultaneously offer a large ferroelectric-antiferroelectric (FE-AFE) phase-switching electric field EA, high electric breakdown strength Eb, and narrow polarization-electric field (P-E) hysteresis loops. In this work, via doping of La3+ into (Pb1-1.5xLax)(Zr0.5Sn0.43Ti0.07)O3 AFE ceramics, large EA and Eb due to respectively enhanced AFE phase stability and reduced electric conductivity, and slimmer hysteresis loops resulting from the appearance of the relaxor AFE state, are successfully obtained, and thus leading to great improvement of the Wre and η. The most superior energy storage properties are obtained in the 3?mol% La3+-doped (Pb1-1.5xLax)(Zr0.5Sn0.43Ti0.07)O3 AFE ceramic, which simultaneously exhibits at room temperature a large Wre of 4.2?J/cm3 and a high η of 78%, being respectively 2.9 and 1.56 times those of (Pb1-1.5xLax)(Zr0.5Sn0.43Ti0.07)O3 AFE ceramics with x?=?0 (Wre?=?1.45?J/cm3, η?=?50%) and also being superior to many previously published results. Besides, both Wre and η change very little in the temperature range of 25–125?°C. The large Wre, high η, and their good temperature stability make the Pb0.955La0.03(Zr0.5Sn0.43Ti0.07)O3 AFE ceramic attractive for preparing high pulsed power capacitors useable in various conditions.  相似文献   

6.
In this work, we report the polymorphic phase transitions(PPT) in ferroelectric Ba0.95Sr0.05ZrxTi(1-x)O3 (BSZT, x = 0.01–0.10) ceramics synthesized by using a solid-state reaction method. The doping elements and composition ratios were selected to create adjoining PPT phase boundaries near room temperature, hence to achieve a broadened peak of piezoelectric performance with respect to composition. The temperature-composition phase diagram was constructed and the effects of PPT on the electromechanical and ferroelectric properties of the ceramics were investigated. It was revealed that the two adjacent PPT regions at room temperature showed different characteristics in property enhancement. However, due to the proximity of the phase boundaries, Ba0.95Sr0.05ZrxTi(1-x)O3 ceramics in a fairly broad range of compositions (0.02  x  0.07) showed excellent piezoelectric properties, including a large piezoelectric constant (312 pC/N  d33  365 pC/N) and a high electromechanical coupling coefficient kp (0.42  kp  0.49).  相似文献   

7.
Ferroelectric materials under shock compression can generate current and power by a drastic change of the remnant polarizations and surface bound charge. This behavior has been employed in applications involving nuclear fusion trigger, energy storage devices, and high pulse power sources. Despite the large power output in lead-containing ferroelectrics, lead-free materials are highly desirable owing to the environmental concerns. Herein, the phase transition behaviors and current outputs of 0.92Bi0.5Na0.5TiO3-0.08BiAlO3 (BNT-8BA) materials are studied under high pressure. The BNT-8BA ferroelectric ceramics can be completely depolarized from polar to the nonpolar state under shock compression, resulting in a current output in the external circuit. The phase-transition-induced depolarization pressures of BNT-8BA are lower than those of the pure Bi0.5Na0.5TiO3 under both dynamic and static high-pressure loads. These results can allow the understanding of the high-pressure behavior of BNT-8BA for application as ferroelectric pulsed power supply.  相似文献   

8.
Low-temperature sintering behaviour and ferroelectric properties of lead zirconate titanate (PZT95/5) ferroelectric (FE) ceramics doped with CdO were investigated. The addition of CdO significantly promoted the densification and decreased the sintering temperature of PZT95/5 ceramic. When the addition of CdO content is 1?mol-%, PCZT95/5 ceramics with a relative high density of approximately 97.5% can be obtained by sintering at 1100°C and exhibits excellent electric properties with d33 values of 65 pC/N, this d33 value is close to that of PZT95/5 ceramic sintered at 1350°C. With an increase in the CdO content, the FE phase content decreases and the antiferroelectric (AFE) phase content increases gradually. When the CdO content is 2?mol-%, the most of FE phase of PCZT 95/5 ceramics changes to AFE phase, the polarisation value is quite small and the d33 value drops to zero.  相似文献   

9.
Ferroelectric (1-x)Sr0.875Pb0.125TiO3-xBi(Mg0.5Zr0.5)O3 ((1-x)SPT-xBMZ, x = 0-0.2) ceramics with high discharge efficiency and power density were synthesized via a conventional solid-state sintering method. The prepared (1-x)SPT-xBMZ ceramics were detected as a pure perovskite structure and a dense microstructure, and a typical relaxor behavior and an excellent temperature stability were also observed. Although there is no direct correlation between the degree of diffuseness and the maximum polarization, the high degree of diffuseness can reduce the remanent polarization and significantly improve energy storage and release characteristics of ferroelectric ceramics. Based on a polarization electric-field loop measurement, a recoverable energy storage density of 0.762 J/cm3 and a very high efficiency of 96.34% are achieved when x = 0.2 under 150 kV/cm. The energy storage properties of 0.8SPT-0.2BMZ ceramic exhibit good temperature stability (25−130 °C) and frequency stability (2−80 Hz). In a practical charge-discharge circuit testing, a short discharge pulse-period about 94 ns, a high discharge energy density of 1.7 J/cm3 and an ultra-high-power density of 62.8 MW/cm3 are obtained for the 0.8SPT-0.2BMZ ceramic at 240 kV/cm. The results indicate that the 0.8SPT-0.2BMZ ceramic is a promising dielectric material for high-power pulse capacitors.  相似文献   

10.
《Ceramics International》2016,42(11):12875-12879
Pb0.94−xLa0.04Srx[(Zr0.6Sn0.4)0.84Ti0.16]O3 (x=0,0.02,0.04,0.06) antiferroelectric ceramics were fabricated via conventional solid-state reaction. The increase of Sr content enhanced the stability of antiferroelectric phase, which resulted in the rise of phase transition fields and energy density. When x=0.06, the releasable energy density was 1.52 J/cm3 and the efficiency was 93.3% under 129 kV/cm. The pulsed discharge current was also measured to evaluate the energy release properties. Under 129 kV/cm, the obtained current density could be as high as 165.5 A/cm2. The pulsed discharge energy density was 1.21 J/cm3 and 90% of that could be released in less than 200 ns. The high energy density, high efficiency and fast energy release time indicate that the obtained AFE ceramics are very promising for pulsed power capacitors.  相似文献   

11.
《Ceramics International》2020,46(11):19103-19110
High power piezoelectric ceramics 0.04Bi(Ni1/2Ti1/2)O3-xPb(Mn1/3Nb2/3)O3-(0.96-x)Pb(ZryTi1-y)O3 (BNT-xPMnN-PZyT) with various contents of PMnN from 0 to 12 mol% (keep y = 0.50) and Zr/Ti ratio gradually increasing from 48/52 to 52/48 (keep x = 0.06) were prepared by solid-state method. X-ray diffraction (XRD) results show a single phase of polycrystalline perovskite and indicate that the phase structure transforms from tetragonal phase to rhombohedral with x and y increasing. The optimal comprehensive properties of BNT-xPMnN-PZyT ceramic, d33 (355 pC/N), kp (0.58), εr (1512), tanδ (0.40%), Tc (336 °C) and Qm (2010), are obtained at x = 0.06 and y = 0.50, which are apparently superior to typical or commercial Pb(Zr,Ti)O3 (PZT) based power ceramics. Within the range from room temperature to 200 °C, the variation of electric-field induced strains is less than 8.3%, indicating its good temperature stability. The maximum vibration velocity of the ceramic at temperature rise of 20 °C is measured to be 0.92 m/s, which is about 2 times higher than that of commercial hard PZT ceramics, suggesting the BNT-xPMnN-PZyT ceramic is a competitive and potential candidate for power piezoelectric transduction and actuation applications.  相似文献   

12.
To develop high-performance piezo-/ferroelectric materials, Bi(Zn½Ti½)O3–PbZrO3–PbTiO3 (BZT–PZ–PT) ternary solid solution with compositions around the morphotropic phase boundary (MPB) is synthesized by solid-state reaction. The crystal structure and electric properties are investigated systematically by X-ray powder diffraction (XRD), dielectric spectroscopy, and ferroelectric and piezoelectric measurements. On the basis of the results of the XRD, dielectric and ferroelectric measurements, the pseudo-binary phase diagram of the yBi(Zn½Ti½)O3–(1 − y)[(1 − x)PbZrO3xPbTiO3] system has been constructed for three series, namely, y = 0.05, 0.10, and 0.15. It is found that the introduction of BZT into the PZT system makes the paraelectric to ferroelectric phase transition more diffuse, brings the MPB to a lower PT content, and enlarges the MPB region. The best properties with an improved dielectric constant ε' = 1248, and a large remnant polarization Pr = 33 μC/cm2, as well as a relatively high TC = 286°C, and a high coercive field Ec = 23 kV/cm was achieved in the y = 0.15 series with MPB composition x = 0.425, making it a promising material for high-power piezoelectric applications.  相似文献   

13.
《Ceramics International》2020,46(1):180-185
A sample of 0.83Pb(Zr0.5Ti0.5)O3-0.11Pb(Zn1/3Nb2/3)O3-0.06Pb(Ni1/3Nb2/3)O3 (PZNNT) to which MnO2 was added, with a high mechanical quality factor (Qm) and a good transduction coefficient (d33×g33), were systematically investigated. Based on the SEM analysis there existed two kinds of “secondary phases”, Rich Ti and Rich Zn phases, which arose due to the B-site substation of PZNNT-based ceramics by manganese ions. One phase was due to the Mn3+ replacing the Ti4+ to create oxygen vacancies and induce the hardening effect. Another phase was due to the Mn2+ replacing the Zn-site to stabilize the perovskite phase. When the addition of MnO2 reached the solubility limit of 1.5 mol% in the PZNNT-based ceramics, the sample showed optimal electrical properties (Qm=357, d33×g33=9859 × 10−15 m2/N, kp=0.56), which suggested its potential application for piezoelectric energy harvesting in larger field excitation environments.  相似文献   

14.
周静  陈文  徐庆  崔万秋 《陶瓷学报》2002,23(3):160-162
通过分析PZSN系材料的介电温度与介电频率曲线 ,发现PZSN系材料没有明确的相变温度 ,相变属弥散型相变。 12 5K与 4M处的介电频率峰对应O -Ti-O与O -Zr -O的偶极子的空间取向的响应行为 ,在顺电相T >Tcav时这种偶极子是不存在的 ,说明它们的行为与相变有关  相似文献   

15.
Lead‐free ferroelectric ceramics (1–x)(Ba0.7Ca0.3)TiO3xBa(Zr0.2Ti0.8)O3 (BCTZ100x) with x = 0.20, 0.30, 0.40, 0.50, 0.60, 0.70, and 0.80 were evaluated for their pyroelectric energy harvesting performance, using the Olsen cycle. As the composition ratio x increased, the crystal phase changed to tetragonal, orthorhombic, rhombohedral, and cubic; the phase boundaries crossed each other in the vicinity of BCTZ70. The crossover phase transition behavior between first‐order and diffuse phase transition changed to only the diffusion phase transition with increasing x. A pinching effect occurred because an increase in dielectric constant was also observed. Energy densities ND of 229 mJ/cm3 and 256 mJ/cm3 for BCTZ50 and BCTZ80 were obtained, respectively, in temperature of 30°C‐100°C and an electric field of 0‐30 kV/cm. These ND values are over two times higher than that of soft–Pb(Ti,Zr)O3 (PZT), which exhibits piezoelectric performance equivalent to BCTZ50 at room temperature. Compared with soft–PZT, BCTZ50 and BCTZ80 exhibited larger ND values owing to their lower Curie temperatures (TC ~ 50°C‐110°C). We conclude that low–TC ferroelectrics are useful for pyroelectric energy conversion based on the Olsen cycle even if they are unsuitable for piezoelectric applications at high temperatures.  相似文献   

16.
17.
BaTiO3 (BT)-based ceramics usually exhibit superior quasi-static piezoelectric response but relatively low electrostrain, which limits their actuator applications. In this study, lead-free (Ba0.835+xCa0.165-x)(Ti0.91Zr0.09)O3 (x = 0–0.06) (BaxCTZ) ceramics with the compositions close to the tetragonal (T)-rich side of orthorhombic (O)-T polymorphic phase boundary (PPB) were reported to exhibit a field insensitive giant dynamic piezoelectric response (d33* >1050 pm/V) over a wide electric field range up to 2 kV/mm, resulting in the large strain value of ∼0.21 %. Detailed structural investigations combined with various electrical properties measurements reveal that the superior dynamic piezoelectric response is attributed to the combination of piezoelectric effect and domain switching behavior due to the chemical modulated O-T PPB, and the field induced partially irreversible T-O phase transition. The results demonstrate that the studied compositions have great potential for applications of lead-free actuator piezoceramics.  相似文献   

18.
《Ceramics International》2021,47(18):25901-25909
Dielectric tunable properties in ferroelectric ceramics have been optimized by a variety of approaches, e.g., isovalent/aliovalent substitution, system composite et al., while the study of non-stoichiometric regulation on the performance of BCZT ceramics was rarely concerned. Herein, a series of novel non-stoichiometric (Ba0·91Ca0.09)x (Zr0·18Ti0.82)O3 (BCZTx) ceramic specimens were successfully prepared via solid-state reaction. The microstructures of BCZTx ceramics are simultaneously investigated through XRD and SEM. The diffuse phase transition (DPT) behaviour of BCZTx ceramics are studied by the Lorentz-type empirical formula. The significant enhancement of DPT behaviour is observed at x = 1.03, which probably due to the coaction of the generation of partial Schottky defects and prominent reduction of grain size. Furthermore, a high tunability (k) 87.80%, low dielectric loss (tan δ) 0.141%, and a remarkably enhanced FOM of 623 are achieved in x = 0.99 at a low DC bias electric fields (BEFs) of 7.28 kV/cm and room temperature (RT), which is superior to that of the stoichiometric BCZT ceramics and other available reported BT-based ceramics systems in term of the dielectric tunable properties. Meanwhile, it shows that the temperature dependent CQF value of x = 0.99 remained advantageous around the RT. These findings suggested that non-stoichiometric BCZTx ceramics with x = 0.99 are significantly competitive in the applications of dielectric tunable devices at RT. The non-stoichiometric regulation is an effective approach in improving the dielectric tunability properties of BCZT ceramics.  相似文献   

19.
《Ceramics International》2017,43(16):13233-13239
Fe3+-doped (Pb0.94Sr0.05La0.01)(Zr0.53Ti0.47)O3 (PSL(ZT)1-x-Fex) piezoelectric ceramics were prepared by the solid-state reaction method and with a variation of the Fe3+ content. When the Fe3+ content was less than 0.010, the ceramics exhibited the features of soft piezoelectric ceramics with a large remnant polarization (Pr) of 35.7 μC/cm2, a large bipolar strain of 0.22% and a high piezoelectric coefficient (d33) of 412 pC/N. The number of oxygen vacancies increased and the domain walls were pinned by the defect diploes with a further increase of the Fe3+ content. Meanwhile, the PSL(ZT)1-x-Fex ceramics showed typical hard behavior and the mechanical quality factor Qm was as high as 500. The softening-hardening transition of electrical properties was also systematically analyzed by adjusting the oxygen vacancies, the space charges and the difference between the unipolar strain and the value of d33×E.  相似文献   

20.
《Ceramics International》2020,46(14):22575-22580
(Pb, La)(Zr, Sn, Ti)O3 (PLZST) ceramic is one of the most prospective antiferroelectric (AFE) materials for variety of functional applications including energy storage and converter. Systematic structural investigation of domain structures should be of fundamental importance for understanding the structure-property relationship in AFE ceramics. In this study, the hierarchical domain structures and modulated structures correlated to the compositional variation in (Pb0.97La0.02) (Zr0.50SnxTi0.50-x)O3 (x = 0.375, 0.45 and 0.50) were observed and investigated in details by transmission electron microscopy. The PLZST ceramics show exclusively incommensurate modulated structures (IMS) whose modulation period changed from 9.37 to 6.15 and to 4.04 with increasing of the x value. The hierarchical domain structures include, in decreasing scales, AFE domains, incommensurate domains and nanodomains. The elementary domains in PLZST ceramics are pinstriped nanodomains which were formed based on IMS configuration but by frequent modulation of IMS periodicity and formation of faults. Nanodomains accumulated and then dissociated into incommensurate domains and AFE domains successively. The presently revealed structural characteristics in antiferroelectric PLZST may stimulate future researches on the evolution of IMS-based hierarchical domains under external physical fields, e.g. thermal or electrical, and their correlation to the physical performance.  相似文献   

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