Piezoelectric properties of MnO2 doped low temperature sintering Pb(Mn1/3Nb2/3)O3–Pb(Ni1/3Nb2/3)O3–Pb(Zr0.50Ti0.50)O3 ceramics

In this study, in order to develop the composition ceramics for low loss and low temperature sintering multilayer piezoelectric actuator, Pb(Mn_1/3Nb_2/3)O₃–Pb(Ni_1/3Nb_2/3)O₃–Pb(Zr_0.50Ti_0.50)O₃ (abbreviated as PMN-PNN-PZT) ceramics were fabricated using Li₂CO₃ and Na₂CO₃ as sintering aids, and their piezoelectric and dielectric characteristics were investigated according to the amount of MnO₂ addition. At the 0.2 wt% MnO₂ doped specimen sintered at 900 °C, density and mechanical quality factor (Q _m) showed the maximum values of 7.81[g/cm³]and 1186, respectively. And also, at 0.1 wt% MnO₂ doped specimen, electromechanical coupling factor (k _p), piezoelectric constant (d ₃₃) of specimen showed the maximum values of 0.608 and 377[pC/N], respectively. Dielectric constant (? _r) slightly decreased with increasing MnO₂. Taking into consideration the density of 7.81[g/cm³], electromechanical coupling factor (k _p)of 0.597 the mechanical quality factor (Q _m) of 1,186, and piezoelectric constant (d ₃₃) of 356[pC/N], it could be concluded that 0.2 wt% MnO₂ doped composition ceramics sintered at 900 °C was best for low loss and low temperature sintering multilayer piezoelectric actuator application.     

Piezoelectric characteristics of low temperature sintering Pb(Ni1/3Nb2/3)O3–Pb(Zr1/2Ti1/2)O3 ceramics as a function of Pb(Mn1/3Sb2/3)O3 substitution

In this study, in order to develop the composition ceramics for multilayer ceramic for ultrasonic nozzle and ultrasonic actuator application, Pb(Mn_1/3Sb_2/3)O₃ (abbreviated as PMS) substituted Pb(Ni_1/3Nb_2/3)O₃–Pb(Zr,Ti)O₃ (abbreviated as PNN-PZT) ceramics were fabricated using two-stage calcinations method and Li₂CO₃, Na₂CO₃ and ZnO as sintering aids, and their piezoelectric and dielectric characteristics were investigated. With the increase of the amount of PMS substitution, electromechanical coupling factor (k _p), and mechanical quality factor (Q _m) of specimens showed the maximum value at 3 mol% substituted specimen while dielectric constant (? _r) was decreased. At the sintering temperature of 900 °C, the density, ? _r, k _p, and Q _m of 3 mol% PMS substituted PNN-PZT composition ceramics showed the optimal values of 7.92 [g/cm³], 959, 0.584, and 1003, respectively, for low loss multilayer piezoelectric actuator application.     

Dielectric and pyroelectric properties of Li2CO3 doped 0.2Pb(Mg1/3Nb2/3)O3–0.5Pb(Zr0.48Ti0.52)O3–0.3Pb(Fe1/3Nb2/3)O3 ceramics

Relaxor ferroelectric compositions of 0.2Pb(Mg_1/3Nb_2/3)O₃–0.5Pb(Zr_0.48Ti_0.52)O₃–0.3Pb(Fe_1/3Nb_2/3)O₃ (0.2PMN–0.5PZT–0.3PFN) ceramics were doped with different concentrations of Li₂CO₃ and were prepared by a columbite precursor process. Their structural, dielectric and pyroelectric properties were studied. A phase analysis was performed using the X-ray diffraction patterns from 2θ?=?44° to 46°, over which the tetragonal phase displays two peaks, (002)_T and (200)_T, while the rhombohedral phase displays one peak, (200)_R. A well saturated P–E hysteresis loop was obtained for the 0.2PMN–0.5PZT–0.3PFN ceramic doped with 0.2 wt.% Li₂CO₃, and the values for the remnant polarization (P _r) and coercive field (E _c) were 30 μC/cm² and 5.4 kV/cm, respectively. A maximum value of the pyroelectric coefficient, 518 μC/m²K, was obtained for the 0.2PMN–0.5PZT–0.3PFN ceramic doped with 0.3 wt.% Li₂CO₃ at the maximum temperature (T _max) due to the decrease of the binding energy for the polarization charge which in formed at the surface.     

Piezoelectric and dielectric characteristics of low-temperature-sintering Pb(Mg1/2W1/2)O3–Pb(Ni1/3Nb2/3)O3–Pb(Zr,Ti)O3 ceramics according to the amount of PNN substitution

In this study, in order to develop low-temperature-sintering ceramics for multilayer piezoelectric actuator, Pb(Mg_1/2W_1/2)O₃–Pb(Ni_1/3Nb_2/3)O₃–Pb(Zr,Ti)O₃ (abbreviated as PMW–PNN–PZT) ceramics were fabricated using Li₂CO₃ and CaCO₃ as sintering aids and their dielectric and piezoelectric properties were investigated with the amount of Pb(Ni_1/3Nb_2/3)O₃ (abbreviated as PNN) substitution. PMW–PNN–PZT composition ceramics could be sintered up to 870°C by adding sintering aids. At the sintering temperature of 900°C, electromechanical coupling factor (k _p), piezoelectric constant (d ₃₃) and Curie temperature (Tc) in the composition ceramics with 9 ;mol% PNN substitution showed the optimal value of 0.64 517 ;pC/N and 317°C, respectively for multilayer actuator application.     

Properties of (001)-textured Pb(Mg1/3Nb2/3)O3–PbTiO3 thin films

Relaxor ferroelectric Pb(Mg_1/3Nb_2/3)O₃–PbTiO₃ (PMN–PT) thin films with [001] preferential orientation were deposited on platinized silicon wafers by a sol–gel method, in which a PbO seeding layer was involved. The influences of annealing temperature on the crystal phase, microstructure, and electrical properties of the PMN–PT films were investigated. Pyrochlore-free perovskite PMN–PT films could be formed on PbO-seeded Pt(111)/Ti/SiO₂/Si wafers at 800 °C, which was also the optimal annealing temperature for endowing the film with the best ferroelectric and dielectric properties. The enhanced properties were attributed to the improved crystallinity and microstructure. The leakage behaviors of the PMN–PT films annealed at different temperatures were also measured and discussed.     

Synthesis and characterizations of the (1 − x)Pb(Sc1/2Nb1/2)O3–xPbTiO3 solid solution ceramics

We report a systematic study of the (1???x)Pb(Sc_1/2Nb_1/2)O₃–xPbTiO₃ (PSN–PT) solid solution in the form of ceramics with compositions at or near the morphotropic phase boundary (MPB) region (0.35?≤?x?≤?0.50). The PSN–PT ceramics have been synthesized by an improved two-step wolframite precursor method. The synthetic process has been optimized in terms of calcining and sintering conditions. Both dielectric permittivity measurements and differential scanning calorimetry (DSC) show a clear peak at T _C, at which the transition from the paraelectric to ferroelectric phase takes place. Interestingly, the solid solution of the MPB compositions displays a T _C?>?200 °C, i.e. higher than the T _C of the Pb(Mg_1/3Nb_2/3)O₃–PbTiO₃ and Pb(Zn_1/3Nb_2/3)O₃–PbTiO₃ solid solutions, making the PSN–PT system very promising piezoelectric and ferroelectric materials for high-temperature applications. A dielectric maximum as high as 50,000 is obtained for the 0.65PSN–0.35PT ceramic with losses smaller than 0.05. The values of the remnant polarization and the strain level of the PSN–PT ceramics are comparable to those of the PZT ceramics.     

Pb(Mg1/3Nb2/3)O3 and (1 − x)Pb(Mg1/3Nb2/3)O3 − xPbTiO3 Relaxor Ferroelectric Thick Films: Processing and Electrical Characterization

The lead magnesium niobate [Pb(Mg_1/3Nb_2/3)O₃ or PMN], and its solid solutions with lead titanate (PbTiO₃ or PT), are of great interest because of their high electromechanical properties. At large PMN content, these materials exhibit relaxor characteristics with large electrostrictive strains and a large permittivity, while compositions near the morphotropic phase boundary present very interesting piezoelectric properties. So far, properties of these materials in ceramic, thin film and single-crystal form have been investigated. In this paper, we report on preparation and properties of pyrochlore free PMN and 0.65PMN-0.35PT thick films (thickness = 10 to 20 m). The films were prepared from ethyl cellulose ink by screen printing on alumina substrate. The influence of various parameters, such as powder characteristics, inks formulation and films sintering conditions, on films densification are discussed. The dielectric and electromechanical properties of the films were examined. Relaxor-like behaviour was clearly demonstrated in PMN films. The maximum relative permittivity for PMN film was 10000 (at 0.1 kHz), which is lower than in bulk ceramics (17800 at 0.1 kHz) prepared under the same conditions. For 0.65PMN-0.35PT, the maximum relative permittivity was around 15500 against 24000 in the bulk. Several parameters, which might be responsible for the lower permittivity, are discussed. Poled 0.65PMN-0.35PT thick films exhibit relatively large piezoelectric response (d ₃₃ up to 200 pm/V) and unipolar strains approaching 0.1%, making these films of interest for various actuator and transducer applications.     

DIELECTRIC AND PIEZOELECTRIC CHARACTERISTICS OF 0.07Pb (Mn1/3Nb2/3) O3 −0.10Pb (Ni1/3Nb2/3) O3− 0.83Pb(Zr0.48Ti0.52) O3 CERAMICS ACCORDING TO THE HEATING RATE

ABSTRACT

In this study, in order to develop the composition ceramics for low loss multilayer piezoelectric actuator, 0.07Pb (Mn_1/3Nb_2/3) O₃ ?0.10Pb (Ni_1/3Nb_2/3) O₃? 0.83Pb(Zr_0.48Ti_0.52) O₃ (abbreviated as PMN-PNN-PZT) ceramics were fabricated using Li₂CO₃, Bi₂O₃ and CuO as sintering aids and according to variation of heating rate. And also, their dielectric and piezoelectric properties were investigated. At the heating rate of 700°C/h and sintering temperature of 900°C, density, electromechanical coupling coefficient (kp), mechanical quality factor (Qm), dielectric constant (ε _r ) and piezoelectric constant (d₃₃) of PMN-PNN-PZT ceramics showed the excellent values of 7.67 g/cm³, 0.58, 1199, 1560 and 380 pC/N, respectively for low loss multilayer piezoelectric actuator application.     

Synthesis and Dielectric Characterization of Pyrochlore-Free Pb1−x Ba x (Zn1/3Nb2/3)O3 Ceramics

The dielectric properties and synthesis of pyrochlore-free lead zinc niobate ceramics with Ba substituting for Pb were investigated. Ba partial substitution for Pb was effective in stabilizing the perovskite structure in PZN ceramics, where the minimum amount of Ba substitution needed was about 20 mol%. The dielectric loss and the temperature coefficient of dielectric constant of PZN were reduced markedly with Ba substitution, while the dielectric constant was greater than 110. Good dielectric properties were obtained for the composition of Pb_0.3Ba_0.7(Zn_1/3Nb_2/3)O₃: = 133.5, tan = 0.0009, = –811 ppm/°C.     

Study of the electrical properties of Pb(Zn,Ni)1/3Nb2/3O3–PbTiO3 ceramics across the morphotropic phase boundary

Structure and electrical properties of (1???x)Pb(Zn_0.2Ni_0.8)_1/3Nb_2/3O₃–xPbTiO₃ ceramics with x?=?0.24–0.38 were examined in detail. X-ray diffraction measurements reveal that all samples are in pure perovskite phase, and most of them lie within the morphotropic phase boundary (MPB) region. The dielectric behaviors of all compositions are characterized with diffuse phase transition and frequency dispersion. The variable power law and the Vogel–Fulcher relation have been used to describe such dielectric behaviors. The highest dielectric constant and the largest piezoelectric coefficient are simultaneously observed when x?=?0.30. The variation of the ferroelectric property with PT content is also discussed.     

Piezoelectric and Dielectric Properties of Pb(Zr x Ti1 − x )O3-Pb(Ni1/3Sb1/3Nb1/3)O3 Piezoelectric Ceramics

In this paper, piezoelectric and dielectric properties of 0.9PbZr_xTi_1–xO₃-0.1PbNi_1/3Sb_1/3Nb_1/3O₃ were studied as a function of Zr/Ti mole ratio(x) for application to piezoelectric actuator. Also, microstructure and crystalline phase are investigated by using SEM and XRD, respectively. As a results, the substitution of Sb5+ to B-site increases the piezoelectric and dielectric properties, and when Zr/Ti mole ratio is 49/51 and ternary mole ration is 0.1(0.9PbZr_0.49Ti_0.51O₃-0.1PbNi_1/3Sb_1/3Nb_1/3O₃), the corresponding composition were found belonging to the Morphotropic Phase Boundary region with electromechanical coupling coefficient(k_p), mechanical quality factor (Q_m), permittivity(_r) and piezoelectric strain constant(d₃₃) equaled to 63%, 360, 2000 and 470 pC/N, respectively. Sintering temperature was about 1150_C and Curie temperature was determined around 290_C.     

Effect of additive SrWO4 on microwave dielectric properties of SrTiO3–Sr(Mg1/3Nb2/3)O3 ceramics

The crystal structure and the properties of a new microwave dielectric ceramics x SrTiO₃–(1???x)Sr(Mg_1/3Nb_2/3)O₃ have been investigated. With x?=?0.025, The new microwave dielectric ceramic achieves the dielectric properties of a dielectric constant ? _r ～27.8, a Q?×?f value ～26,800, and a τ _f value ～7.4 ppm/°C. When the SrWO₄ is added, the sintering temperature of x SrTiO₃–(1???x)Sr(Mg_1/3Nb_2/3)O₃ ceramics will fall to 1350 °C, and its Q?×?f value can be improved further and the τ _f value becomes smaller. When the SrWO₄ is added by 0.07 mol, the specimen acquires the following microwave properties: a dielectric constant ? _r ～30.3, a Q?×?f value ～29,500, and a τ _f value of approximately ?0.4 ppm/°C.     

Structural evolution and microwave dielectric properties of (1 − x)BaZn1/3Nb2/3O3 + xBaMg1/2W1/2O3 ceramics

Structural evolution and microwave dielectric properties of (1 − x)BaZn_1/3Nb_2/3O₃ + xBaMg_1/2W_1/2O₃ (0 ≤ x ≤ 1) system have been investigated in this work. All samples exhibit single perovskite phase except for the samples with x = 0 and x ≥ 0.8 in which barium niobate and BaWO₄ second phase existed, respectively. 1:1 cations ordering existed in the samples with x ≥ 0.1, and the ordering degree increases with the increase of x. Liquid phase sintering was observed in the sample with x ≥ 0.8. Dielectric constant decreases almost linearly from 40.8 to 17.4 with increasing x. Q × f value monotonically increases from 26,162 GHz to 64,705 GHz with increasing x. The τ_f value changes from +30 ppm/°C to −27.8ppm/°C. Near zero τ_f value of −1.4 ppm/°C could be obtained at x = 0.4 composition.     

Lead-free piezoelectric ceramics of (Bi1/2Na1/2)TiO3–(Bi1/2K1/2)TiO3–(Bi1/2Ag1/2)TiO3 system

The ternary lead-free piezoelectric ceramics system of 0.90[x(Bi_1/2Na_1/2)TiO₃–(1???x)(Bi_1/2K_1/2)TiO₃]–0.10(Bi_1/2Ag_1/2)TiO₃ (x?=?0.77, 0.79, 0.81, 0.83, 0.85) were successfully synthesized by conventional ceramic sintering technique. The samples were studied by X-ray diffraction, dielectric, ferroelectric and piezoelectric measurements. The MPB composition of the system appears to be near BNKA-79 according to the results of the X-ray diffraction and ferroelectric properties. The sample with x?=?0.79 showed the highest piezoelectric constant d ₃₃?=?160 pC/N. The maximum electromechanical coupling factors, k _p and k _t, are 0.30 for BNKA-79 and 0.42 for BNKA-85, respectively.     

Effect of CuO addition on sintering temperature and piezoelectric properties of 0.05Pb(Al0.5Nb0.5)O3−0.95Pb(Zr0.52Ti0.48)O3+0.7 wt.% Nb2O5 + 0.5 wt.% MnO2 ceramics

Effect of CuO addition on piezoelectric properties of 0.05Pb(Al_0.5Nb_0.5)O₃?0.95Pb(Zr_0.52Ti_0.48)O₃+0.7 wt.% Nb₂O₅ + 0.5 wt.% MnO₂ (PAN-PZT) ceramics was studied to decrease the sintering temperature below 900°C for LTCC. The PAN-PZT ceramics sintered at 1200°C had piezoelectric properties of d ₃₃ = 340 pC/N, k _p = 61.6%, Q _m = 1,725, and density of 7.5 g/cm³. The addition of CuO significantly decreased the sintering temperature due to the formation of liquid phase containing a binary combination of PbO and CuO in grain boundary. Piezoelectric properties of d ₃₃ = 361 pC/N, k _p = 57%, Q _m = 145, and density of 7.8 g/cm³ were achieved at sintering temperature of 900°C. The CuO doped PAN-PZT ceramics show high density and d ₃₃ at low sintering temperature though its electromechanical quality factor abruptly decreases due to the CuO additive effect.     

Microstructure and microwave dielectric properties of (1 − x)Ca(Mg1/3Nb2/3)O3/xCa0.61Nd0.26TiO3 complex perovskite ceramics

Ceramics in the (1?x)Ca(Mg_1/3Nb_2/3)O₃/xCa_0.61Nd_0.26TiO₃ system were prepared and characterized. Single phase solid solutions were obtained up to x?=?0.4, and the crystal structure belonged to monoclinic space group P21(4) for x?=?0.1 and orthorhombic space group Pbnm(62) for x above 0.1. The secondary phase of Ca₂(Ti,Nb)₂O₆ was observed for x?=?0.6 and 0.8. Good combination of microwave dielectric properties was achieved in the present ceramics with x?=?0.4: ? _r?=?46.5, Qf?=?14,136 GHz, τ _f?=??12.5 ppm/°C.     

Low-temperature sintering and dielectric properties of the Bi(Nb1−x Ta x )O4 system

Low-temperature sintering and dielectric properties of the Bi(Nb_1?x Ta _x )O₄ (x?=?0.1, 0.3, and 0.5) system was investigated as a function of the zinc borosilicate (ZBS) glass content with a view to applying this system to LTCC technology. The addition of 7 wt% ZBS glass ensured a successful sintering below 900°C. The complete solid solution of Bi(Nb, Ta)O₄ with an orthorhombic structure was formed and the high temperature form of Bi(Nb, Ta)O₄ with a triclinic structure was not observed. The second phase of Bi₂SiO₅ was observed for all compositions. The non-relative liquid phase sintering (NLPS) occurred and the one-stage sintering was conducted. The Q?×?f values were improved by the addition of Ta. Bi(Nb_0.7Ta_0.3)O₄ with 7 wt% ZBS glass sintered at 900°C demonstrated 35.8 in the dielectric constant (? _r), 2,200 GHz in the quality factor (Q?×?f ₀), and ?48 ppm/°C in the temperature coefficient of resonant frequency (τ _f).     

High-ε Microwave Dielectrics in Pb0.6Ca0.4Zr0.6+x (Fe1/2Nb1/2)0.4−x O3 System

Modification of Pb_0.6Ca_0.4Zr_0.6(Fe_1/2Nb_1/2)_0.4O₃ dielectric ceramics was performed by Zr substitution for (Fe, Nb). The XRD patterns showed that the single phase with orthorhombic distortion unit cell was obtained in the present ceramics. The decreasing dielectric constant by Zr substitution was due to its smaller value of /r ³ _ion. The calculated polarizability was compared with the observed one, and the results showed a good fit, considering the polarizability of oxygen dependent on the V _ox. The Zr substitution on B-site reduced the temperature coefficient of dielectric constant effectively due to the reduced dielectric constant. The effects of tilting transition on the temperature coefficient of dielectric constant were also discussed. The modified microwave dielectric properties were obtained in Pb_0.6Ca_0.4Zr_0.6+x (Fe_1/2Nb_1/2)_0.4–x O₃ for x = 0.3: _r = 100, Q × f = 3,300 to 3,600 GHz, _f = 6–8 ppm/°C.     

Investigation of the BaTiO3–BaMg1/3Nb2/3O3 system: Structural, dielectric, ferroelectric and electromechanical studies

Lead-free (1?x) BaTiO₃ –x BaMg_1/3Nb_2/3O₃ ceramics with x?=?0.03, 0.04, 0.05 and 0.06 were prepared by solid-state synthesis. The effects of the Ba(Mg_1/3Nb_2/3)O₃ addition on the phase composition, dielectric and ferroelectric properties, as well as the electromechanical response of the classic ferroelectric BaTiO₃ were investigated. The room-temperature X-ray diffraction analyses of all the ceramics revealed a perovskite phase after sintering at 1300 °C with a composition-dependent symmetry. The samples with a lower concentration of Ba(Mg_1/3Nb_2/3)O₃, i.e., x?=?0.03 and 0.04, were tetragonal, while the samples with x?=?0.05 and 0.06 were found to be cubic. The result is in agreement with the dielectric, ferroelectric and electromechanical properties. With x increasing from 0.03 to 0.06 the temperature of the diffused maximum of the dielectric permittivity decreased from 348 K to 265 K. All the ceramics showed a large electromechanical response: the calculated room-temperature electrostrictive coefficient M ₃₃ of the sample with x?=?0.06 was 1.4 · 10^?16?m²/V², which is comparable to the value measured for Pb(Mg_1/3Nb_2/3)O₃ ceramics.