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1.
To explore new relaxor‐PbTiO3 systems for high‐power and high‐temperature electromechanical applications, a ternary ferroelectric ceramic system of Pb(Lu1/2Nb1/2)O3–Pb(In1/2Nb1/2)O3–PbTiO3 (PLN–PIN–PT) have been investigated. The phase structure, dielectric, piezoelectric, and ferroelectric properties of the as‐prepared PLN–PIN–PT ceramics near the morphotropic phase boundary (MPB) were characterized. A high rhombohedral‐tetragonal phase transition temperature TR‐T of 165°C and a high Curie temperature TC of 345°C, together with a good piezoelectric coefficient d33 of 420 pC/N, were obtained in 0.38PLN–0.20PIN–0.42PT ceramics. Furthermore, for (0.8?x)PLN–0.2PIN–xPT ceramics, the temperature‐dependent piezoelectric coefficients, coercive fields and electric‐field‐induced strains were further studied. At 175°C, their coercive fields were found to be above 9.5 kV/cm, which is higher than that of PMN–PT and soft P5H ceramics at room temperature, indicating PLN–PIN–PT ceramics to be one of the promising candidates in piezoelectric applications under high‐driven fields. The results presented here could benefit the development of relaxor‐PbTiO3 with enhanced phase transition temperatures and coercive fields.  相似文献   

2.
A ternary ferroelectric ceramic system, (1?x?y)Pb(In1/2Nb1/2)O3xPb(Zn1/3Nb2/3)O3yPbTiO3 (PIN–PZN–PT, x = 0.21, 0.27, 0.36, 0.42), was prepared using a two‐step precursor method. The phase structure, dielectric, piezoelectric, and ferroelectric properties of the ternary ceramics were systematically investigated. A morphotropic phase boundary (MPB) was identified by X‐ray diffraction. The optimum piezoelectric and electromechanical properties were achieved for a composition close to MPB (0.5PIN–0.21PZN–0.29PT), where the piezoelectric coefficient d33, planar electromechanical coupling factor kp, and remnant polarization Pr are 660 pC/N,72%, and 45 μC/cm2, respectively. The Curie temperature TC and rhombohedral to tetragonal phase transition temperature TR?T were also derived by temperature dependence of dielectric measurements. The strongly “bended” MPB in the PIN–PT system was found to be “flattened” after addition of PZN in the PIN–PT–PZN system. The results demonstrate a possibility of growing ferroelectric single crystals with high electromechanical properties and expanded range of application temperature.  相似文献   

3.
Low‐temperature sintering of 0.25PMN–0.40PT–0.35PZ ceramics was investigated using CuO as a sintering aid. Effect of CuO on the sinterability, microstructure, and electric properties of 0.25PMN–0.40PT–0.35PZ system was systematically studied. The CuO addition significantly reduced the sintering temperature of 0.25PMN–0.40PT–0.35PZ from 1260°C to 950°C. SEM results indicated that a dense microstructure without any second phase was obtained when the amount of CuO was 0.25 wt%, which gave rise to high values of d33 = 532 pC/N and kp = 58.4%. A large field‐induced longitudinal strain ~2.28% (at 30 kV/cm) can also be obtained for 0.25 wt% CuO‐added specimens, which shows a great promise for multilayer actuator applications.  相似文献   

4.
Textured piezoelectric ceramics, such as textured Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) ceramics, have attracted considerable attention from both academia and industry, as they possess crystal-like piezoelectric properties, high composition homogeneity, and low manufacturing cost. However, the main difficulty with the textured piezoelectric ceramics is the presence of BaTiO3 (BT) templates, which greatly reduces their piezoelectricity and phase transition temperature. Thus, it is highly recommended to fabricate textured piezoelectric ceramics using as few templates as possible. Here, we successfully fabricated high-quality <001>-textured PMN-28PT ceramics (texturing degree of 99%) by using an extremely small amount of BT templates (1 vol.%) with the help of CuO/B2O3 sintering aids. The textured PMN-28PT ceramic exhibits 80% piezoelectric coefficient (d33 ∼ 1200 pC/N), 96% electromechanical coefficient (k33 ∼ 88%) and the same temperature stability (Trt ∼ 100, Tc ∼ 150°C) when compared to its single crystal counterpart. In addition, by using an alternating current electric field poling (AC-poling), the piezoelectric coefficient d33 and dielectric permittivity ε33 of the textured PMN-28PT ceramics were further enhanced around 5–8%. It is believed that the advantages of high electromechanical properties, low cost, and easy mass production of textured PMN-28PT ceramic will make it a promising candidate for advanced electromechanical devices.  相似文献   

5.
《Ceramics International》2016,42(6):7223-7229
CuO modified Pb(In1/2Nb1/2)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3 (PIN–PMN–PT) ternary relaxor based ferroelectrics with the composition near the morphotropic phase boundary were synthesized by two-step columbite precursor method. The introduction of CuO significantly improved the sinterability of PIN–PMN–PT ceramics, resulting in the full densification of samples at lower sintering temperatures. It also profoundly modified the crystal structure and fracture mode of the ceramics. Properly increasing CuO content led to the disappearance of rhombohedral-tetragonal phase transition, remarkably improved the Curie temperature (Tc), and made the ceramics more relaxorlike. The ternary ceramics doped with 0.25 wt% CuO possessed optimum piezoelectric properties (d33=584 pC/N, d33*=948 pC/N, and kp=0.68), high ferroelectric properties (Ec=9.9 kV/cm, and Pr=33.1 μC/cm2), low dielectric loss (tan δ=0.9%), and wider temperature usage range (Tc=225 °C). The obtained properties are much higher than those of previously reported PIN–PMN–PT based ceramics, indicating that CuO doped PIN–PMN–PT is a promising candidate for electromechanical applications with high performance and wide temperature/electric field usage ranges.  相似文献   

6.
In this article, perovskite‐structured BiFeO3–Bi(Zn1/2Ti1/2)O3–PbTiO3 (BF–BZT–PT) ternary solid solutions were prepared with traditional solid‐state reaction method and demonstrated to exhibit a coexistent phase boundary (CPB) with Curie temperature of TC~700°C in the form of ceramics with microstructure grain size of several micron. It was found that those CPB ceramics fabricated with conventional electroceramic processing are mechanically and electrically robust and can be poled to set a high piezoelectricity for the ceramics prepared with multiple calcinations and sintering temperature around 750°C. A high piezoelectric property of TC = 560°C, d33 = 30 pC/N, ε33T0 = 302, and tanδ = 0.02 was obtained here for the CPB 0.53BF–0.15BZT–0.32PT ceramics with average grain size of about 0.3 μm. Primary experimental investigations found that the enhanced piezoelectric response and reduced ferroelectric Curie temperature are closely associated with the small grain size of microstructure feature, which induces lattice structural changes of increased amount ratio of rhombohedral‐to‐tetragonal phase accompanying with decreased tetragonality in the CPB ceramics. Taking advantage of structural phase boundary feature like the Pb(Zr,Ti)O3 systems, through adjusting composition and microstructure grain size, the CPB BF–BZT–PT ceramics is a potential candidate to exhibit better piezoelectric properties than the commercial K‐15 Aurivillius‐type bismuth titanate ceramics. Our essay is anticipated to excite new designs of high–temperature, high–performance, perovskite‐structured, ferroelectric piezoceramics and extend their application fields of piezoelectric transducers.  相似文献   

7.
Dielectric, ferroelectric, and piezoelectric properties of both random and textured Mn–PMN–PZT ceramics were characterized under uniaxial stress. Textured ceramics exhibit a large piezoelectric response under uniaxial pressure; the bias field piezoelectric constant is higher than 700 pC/N when pressure is below 50 MPa. Moreover, textured ceramics also show better depolarization resistance under uniaxial stress fields; overall, 30% of the origin performance will remain when stress approaches 200 MPa, but for random ceramics, it is only 10%. The ferroelectricity of both random and textured ceramics is suppressed by uniaxial compression. Ec, Pr, Ei, and dissipation energy all decrease with increasing uniaxial stress. In addition, phase-field simulation was used to better understand the polarization-changing effects on piezoelectric and dielectric performance. The uniaxial stress causes polarization rotation and increases the angle between polarization and the electric field, which is an important factor leading to the increase of the dielectric constant.  相似文献   

8.
Rhombohedral 0.69Pb(Zr0.47Ti0.53)‐0.31Pb(Zn0.6Ni0.4)NbO3 (PZT‐PZNN) ceramics were textured using 10.0 vol. % BaTiO3 (BT) platelets along the <001> direction at 950°C with a high Lotgering factor of 95.3%. BT platelets did not react with the PZT‐PZNN ceramics, and the textured PZT‐PZNN ceramic had a tetragonal structure. The PZT‐PZNN ceramics exhibited a strain of 0.174% with a piezoelectric strain constant (d*33) of 580 pC/N at 3.0 kV/mm. The textured PZT‐PZNN ceramic showed an increased strain of 0.276% and d*33 of 920 pC/N at 3.0 kV/mm, which can be explained by the domain rotation. However, the d33 values of the textured specimens are smaller than those of the untextured specimens because of the small remanent polarization and relative dielectric constant of BT platelets. The textured PZT‐PZNN ceramic synthesized in this work can be used for piezoelectric multilayer actuators because of its large strain and low sintering temperature.  相似文献   

9.
New binary system (1?x) PbTiO3?xBi(Ni1/2Zr1/2)O3 (PT–100x BNZ) with ≤ 0.45 were synthesized via solid‐state reaction route. A morphotropic phase boundary (MPB) was identified around x = 0.40 by X‐ray diffraction (XRD) method. The ceramics with MPB composition exhibit enhanced ferroelectric properties. A large piezoelectric coefficient (d33) up to 400 pC/N was obtained for the PT–40BNZ, which is comparable with the PbTiO3–BiScO3 (PT–BS, 450 pC/N).The frequency dependence of dielectric permittivity of PT–40BNZ shows characteristic of a strong relaxor feature and a transition temperature around 290°C (1 MHz). Temperature effect on the unipolar strain was also investigated. The present system with high d33 is a competitive piezoelectric material, as no expensive oxide is used here compared with the PT–BS.  相似文献   

10.
0.725BiFe1?xScxO3–0.275BaTiO3 + y mol% MnO2 multiferroic ceramics were fabricated by a conventional ceramic technique and the effects of Sc doping and sintering temperature on microstructure, multiferroic, and piezoelectric properties of the ceramics were studied. The ceramics can be well sintered at the wide low sintering temperature range 930°C–990°C and possess a pure perovskite structure. The ceramics with x/y = 0.01–0.02/1.0 sintered at 960°C possess high resistivity (~2 × 109 Ω·cm), strong ferroelectricity (Pr = 19.1–20.4 μm/cm2), good piezoelectric properties (d33 = 127–128 pC/N, kp = 36.6%–36.9%), and very high Curie temperature (618°C–636°C). The increase in sintering temperature improves the densification, electric insulation, ferroelectric, and piezoelectric properties of the ceramics. A small amount of Sc doping (x ≤ 0.04) and the increase in the sintering temperature significantly enhance the ferromagnetic properties of the ceramics. Improved ferromagnetism with remnant magnetization Mr of 0.059 and 0.10 emu/g and coercive field Hc of 2.51 and 2.76 kOe are obtained in the ceramics with x/y = 0.04/1.0 (sintered at 960°C) and 0.02/1.0 (sintered at 1050°C), respectively. Because of the high TC (636°C), the ceramic with x/y = 0.02/1.0 shows good temperature stability of piezoelectric properties. Our results also show that the addition of MnO2 is essential to obtain the ceramics with good electrical properties and electric insulation.  相似文献   

11.
The poling effect on the [011]‐oriented (1?x)Pb(Mg1/3Nb2/3)O3xPbTiO3 (PMN–xPT) single crystals across the morphotropic phase boundary (MPB) was studied. The dielectric and piezoelectric properties were investigated as a function of the poling field. Domain structure evolutions during the poling process were recorded. In the unpoled PMN–xPT phase diagram, an apparent rhombohedral (R)‐tetragonal (T) phase boundary exists. With room‐temperature poling, the structure transformation sequence strongly depends on the composition. The crystal experiences a direct transition to the 2R/2T domain state in the rhombohedral or tetragonal phase field beyond the MPB region, whereas within the MPB zone it is hard to achieve the 2R/2T engineered configuration although the initial state is either rhombohedral or tetragonal as well. The piezoelectric responses of the MPB·PMN–xPTs are extraordinary weak (d33 ~ 250 pC/N), in contrast to the [011]‐oriented multidomain PMN–xPTs with ultrahigh‐piezoelectric coefficient (d33 > 1000 pC/N). We demonstrate that a slight composition variation near the MPB will significantly influence the domain evolution route and piezoelectricity for the [011]‐oriented PMN–xPT crystals. We also confirm the feasibility to realize the 2R/2T engineered domain configuration for the [011]‐oriented MPB crystals, which will extend the desired portion of the Bridgeman‐grown boules with optimal piezoelectric properties.  相似文献   

12.
Pb (In1/2Nb1/2) O3‐Pb (Sc1/2Nb1/2) O3‐PbTiO3 (PIN‐PSN‐PT) ternary ceramics with compositions near morphotropic phase boundary (MPB) were fabricated by solid‐state‐sintering process. Dielectric and piezoelectric properties of xPIN‐yPSN‐zPT (x = 0.19, 0.23 and z = 0.365, 0.385) ceramics were investigated as a function of temperature, showing high Tr‐t and Tc on the order of 160 ~ 200°C and 280 ~ 290°C, respectively. The xPIN‐yPSN‐0.365PT (x = 0.19 and 0.23) ceramics do not depolarize at the temperature up to 200°C, showing a better thermal stability when compared to the state‐of‐the‐art relaxor‐PbTiO3 systems. A slight variation (<9%) of kp, kt, and k33 was observed in the temperature range of 25°C‐160°C for xPIN‐yPSN‐0.385PT (x = 0.19 and 0.23) ceramics. Rayleigh analysis was employed to quantify the contribution of domain wall motion to piezoelectric response, where the domain wall contribution was found to increase with composition approaching MPB for PIN‐PSN‐PT system.  相似文献   

13.
The charge release and related mechanisms for Pb(In1/2Nb1/2)–Pb(Mg1/3Nb2/3)–PbTiO3 (PIN–PMN–PT) ferroelectric crystals under one‐dimensional shock wave compression were investigated using discharge current profile measurement, by which the piezoelectric stress coefficient e31 and the phase transition (from tetragonal to orthorhombic phase) pressure were obtained, being ?2.9 C/m2 and 2.3 GPa, respectively. Based on experiment results and thermodynamics analysis, it was found that the one‐dimensional shock compression favored ferroelectric phase, being different from the effect of hydrostatic pressure, which favored paraelectric phase. This phenomenon can be attributed to the crystal anisotropy and electromechanical coupling effects as one‐dimensional shock compression is applied to PIN–PMN–PT ferroelectric crystals.  相似文献   

14.
For rhombohedral (R) Pb(In1/2Nb1/2)O3–PbZrO3–Pb(Mg1/3Nb2/3)O3–PbTiO3 (PIN–PZ–PMN–PT) relaxor single crystal, high temperature‐insensitive behaviors under different external stimuli were observed (remnant polarization Pr from 30°C to 180°C and piezoelectric strain d33* from 30°C to 116°C). When electric field E ≥ 50 kV/cm in the case of an activation field Ea = 40‐50 kV/cm was applied, it was found that the domain switching was accompanied by a phase transition. The high relaxor nature of the R phase PIN–PZ–PMN–PT was speculated to account for the large Ea and high piezoelectric response. The short‐range correlation lengths extracted from the out‐of‐plane (OP) and in‐plane (IP) nanodomain images, were 64 nm and 89 nm, respectively, which proved the high relaxor nature due to In3+ and Zr4+ ions entering the B‐site in the ABO3‐lattice and enhancing the disorder of B‐site cations in the R phase PIN–PZ–PMN–PT. The switching process of R nanodomain variants under the step‐increased tip DC voltage was visually revealed. Moreover, the time‐dependent domain evolution confirmed the high relaxor nature of the R phase PIN–PZ–PMN–PT single crystal.  相似文献   

15.
The doping of ZnO is efficient to improve the piezoelectric property and thermal stability of Pb(Mg1/3Nb2/3)O3–PbTiO3 (PMN–PT) based ceramics. However, the underlying physics, especially the local domain structures of the ZnO modified PMN–PT ceramics, which is strongly associated with the electric properties, is not clear yet. In this paper, we investigated the local domain structures and their evolution as a function of x in PMN–0.32PT:xZnO ceramics. It was found that, the domain evolution is mainly caused by the growth of grain size induced by the sintering aiding effect of ZnO at < 0.04, and the domain evolution can be attributed to the phase transition induced by the partial replacement of Mg2+ by Zn2+ in the B-site of PMN–PT lattice at > 0.06. Furthermore, we also investigated the domain structure evolution as functions of temperature and local external electric field in PMN–0.32PT:0.06ZnO ceramics, which exhibited superior piezoelectric property relative to other compositions. We found that the irregular nanodomains are more stable at high-temperature range, and the regular non-180° domains exhibited more complex rotation behavior under local electric field, which probably leads to the thermal stability and piezoelectric property enhancement in the ZnO-modified PMN–0.32PT ceramics.  相似文献   

16.
We investigated the influence of CuO amount (0.5–3.0 mol%), sintering temperature (900°C–1000°C), and sintering time (2–6 h) on the low‐temperature sintering behavior of CuO‐added Bi0.5(Na0.78K0.22)0.5TiO3 (BNKT22) ceramics. Normalized strain (Smax/Emax), piezoelectric coefficient (d33), and remanent polarization (Pr) of 1.0 mol% CuO‐added BNKT22 ceramics sintered at 950°C for 4 h was 280 pm/V, 180 pC/N, and 28 μC/cm2, respectively. These values are similar to those of pure BNKT22 ceramics sintered at 1150°C. In addition, we investigated the performance of multilayer ceramic actuators made from CuO‐added BNKT22 in acoustic sound speaker devices. A prototype sound speaker device showed similar output sound pressure levels as a Pb(Zr,Ti)O3‐based device in the frequency range 0.66–20 kHz. This result highlights the feasibility of using low‐cost multilayer ceramic devices made of lead‐free BNKT‐based piezoelectric materials in sound speaker devices.  相似文献   

17.
Piezoelectric ceramics Pb(Ni1/3Nb2/3)O3–Pb(Mg1/2W1/2)O3–Pb(Sb1/2Nb1/2)O3–Pb(Zr0.39Ti0.61)O3 with Ba(Cu1/2W1/2)O3 sintering aids were fabricated using economical industrial oxide powders and their piezoelectric, dielectric, and ferroelectric properties were investigated in order to develop low‐temperature sintering ceramics for multilayer piezoelectric actuators. A quadratic formula and the Curie–Weiss law reveal that the ceramics are typical displacive‐type ferroelectric relaxors. The ceramics sintered as low as 900°C have good piezoelectric properties of d33 = 551 pC/N, kp = 0.52, εr = 3583, tgδ = 0.02, and TC = 161°C, which is much promising to manufacture multilayer piezoelectric transducers.  相似文献   

18.
Nb and Mn were doped, respectively, to 0.8Pb(Sn0.46Ti0.54)O3–0.2Pb(Mg1/3Nb2/3)O3 (PST–PMN) to improve electrical properties for meeting the requirement in various fields. The additions of Nb and Mn influence in a pronounced way the structure, and improve the densities of the ceramics. Nb‐doped PST–PMN increased the piezoelectric coefficient d33, planar electromechanical coupling kp, and relative dielectric constant ε, indicating “soft” piezoelectric behavior. Mn doping played a “hard” part, which significantly enhanced the mechanical quality factor Qm without deteriorating other piezoelectric properties. The most excellent properties of Nb‐doped PST–PMN were obtained with doping amount of 0.75 mol%, specifically d33, kp, being on the order of 455 pC/N, 57.5% and 3560, respectively. The addition of 0.75 mol% Mn for PST–PMN presented the optimum electrical properties, with Qm of 554, d33 of 430 pC/N, kp of 57.0%, ε of 2770. It was proposed that the addition of Nb, Mn generated different defect dipoles involved in the domain walls motion and intrinsic piezoelectric responses, leading to different effects on electrical properties.  相似文献   

19.
Although rare earth neodymium (Nd) doping is common in Pb(Mg1/3Nb2/3)O3–PbTiO3 (PMN–PT) single crystals, it is rarely reported in PMN–PT ceramics. To explore the effect of Nd doping on PMN–PT ceramics, PMN–30PT:xNd3+ (x = 0%, 1%, 2%, and 3%) relaxor ferroelectric ceramics were fabricated using a solid-state method via two-step sintering. An enhanced piezoelectric charge coefficient (d33) of ∼870 pC/N and a high piezoelectric strain coefficient (d33*) of ∼1025 pm/V were achieved for x = 2%. Through Rayleigh analysis of polarization–electric field (PE) hysteresis loops under small electric fields, it was found that the dielectric property was mainly influenced by the intrinsic contribution (local lattice distortion). Furthermore, by investigating domain configurations, high piezoelectric properties were found to be associated with the domain size reduction and local structural heterogeneity. The results indicate that the PMN–30PT:xNd3+ ceramics is a promising material for electronic devices, and that rare earth Nd doping is an efficient strategy for improving the electronic performance of Pb-based relaxor ferroelectrics.  相似文献   

20.
There is a growing requirement for high‐temperature piezoelectric materials in the petrochemical, automotive, and aerospace industries. Here, the piezoelectric materials of Fe and Mn comodified 0.36BiScO3–0.64PbTiO3 (BS‐PTFMn) ceramics with high Curie temperature (Tc), large mechanical quality factor (Qm), and reduced strain hysteresis were presented. XRD results revealed that all the BS‐PTFMn ceramics have a pure perovskite structure with tetragonal symmetry, and the ratio of c/a is insensitive to the contents of Fe. With the modifications of Fe, the dielectric loss tanδ and strain hysteresis decrease clearly, while the mechanical quality factor improves significantly. The Curie temperature, piezoelectric constant, planar electromechanical coupling factor, dielectric loss, and mechanical quality factor of the BS‐PTFMn with 3% Fe content are 492°C, 235 pC/N, 0.38, 0.6%, and 280, respectively. BS‐PTFMn ceramics show 50°C higher Tc than BS‐PT morphotropic phase boundary composition. The figure of merit (product of Qm, and kij) of BS‐PTFMn ceramics is about five times than that of pure BS‐PT ceramics. Furthermore, for the BS‐PTFMn ceramics with Fe content of 3 mol%, the high field strain coefficient value calculated from the electric‐field‐induced strain curves (Smax/Emax) is 320 pm/V, while the strain hysteresis (under 40 kV/cm) is reduced to one fifth that of unmodified BS‐PT ceramics. Moreover, the temperature‐dependent electromechanical coupling coefficient and dielectric constant are very stable in the temperature range from room temperature (RT) to 450°C. These results indicated that BS‐PTFMn ceramics are promising for high‐temperature piezoelectric applications.  相似文献   

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