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High‐power piezoelectric ceramics are typically driven to output vibration velocity (v0) under high AC electric fields. Herein, the Fe2O3 doped 0.125 Pb(Zn1/3Nb2/3) O3–0.075 Pb(Mn1/3Nb2/3)O3–0.8 Pb(Zr0.48Ti0.52)O3(PZMNZT–xFe; x = 0.05–0.35) piezoelectric ceramics were prepared to enhance v0, and the favorable comprehensive electrical properties, such as d33 = 315 pC/N, Qm = 1738, kp = 0.58, kt = 0.48, εr = 1156, tan δ = 0.4%, and Tc = 320°C, were achieved in the PZMNZT–0.15Fe ceramic. Most importantly, the PZMNZT–0.15Fe ceramic presented a reliable v0 of 0.90 m/s, which was 2.25 times of the commercial PZT4 ceramic (∼0.40 m/s). The excellent high‐power performance should be attributed to ordering functional elements such as crystal grains and ferroelectric domains. Overall, this work reveals that the PZMNZT–0.15Fe ceramic is competitive for high‐power applications. [ABSTRACT FROM AUTHOR]

Magnetoelectric (ME) sensors are an important tool to detect weak magnetic fields in the industry; however, to date, there are no high-quality ME sensors available for high-temperature environments such as engines, deep underground, and outer space. Here, a 0.364BiScO3–0.636PbTiO3 piezoelectric ceramic and Terfenol-D alloy with a Curie temperature of 450 and 380 °C, respectively, were bonded together by an inorganic glue to achieve a high-temperature ME sensor. The ceramic shows a piezoelectric d33 coefficient of 780 pC/N at 420 °C, and the inorganic glue has a high maximum stress of 9.12 MPa even at 300 °C. As a result, the sensor exhibits the maximum ME coefficient αE of 2.008, ∼1.455, and ∼0.906 V cm−1 Oe−1 at 20, 200, and 350 °C, respectively. Most importantly, the magnetic field detecting precision is as small as 42 nT at 20–350 °C. The ME sensor provides an effective solution for the detection of weak magnetic fields in harsh environments. [ABSTRACT FROM AUTHOR]

Bi(Zn1/2Ti1/2)O3−BiScO3−PbTiO3 (BZT−BS−PT) high Curie temperature piezoelectric ceramics were synthesized by the conventional solid‐state reaction method. Systematical investigations on the sintering, piezoelectric, and dielectric properties of the piezoceramics have been conducted. It was found that the sintering temperature could be remarkably depressed by varying the compositions in BZT−BS−PT systems. For composition of 11BZT−34BS−55PT ceramic, the sintering temperature is even lowered down to 750°C without any extra additions of sintering aids. Meanwhile, the ceramic sintered at this ultralow temperature presents dense microstructure with relative density up to 97%, as well as optimal properties of piezoelectric coefficient d33 of 336 pC/N and Curie temperature of 415°C. The mechanism of low sintering temperature may be ascribed to the low melting point bismuth‐based components in BZT−BS−PT solid solutions. Furthermore, 11BZT−34BS−55PT multilayer ceramics have been co‐fired at 750°C with Ag internal electrodes. The dense structures, low cost, and optimal comprehensive properties of the co‐fired multilayers illustrate obvious advantages of the ultralow sintering temperature in LTCC devices, implying promising applications of this Bi(Zn1/2Ti1/2)O3−BiScO3−PbTiO3 high Curie temperature ternary system. [ABSTRACT FROM AUTHOR]

Pb(Zr, Ti)O3(PZT)-based piezoelectric ceramics and Al2O3-based structural ceramics were cast and co-fired to prepare a layered piezoelectric ceramic/structural ceramic composite. Considering the significant differences in sintering characteristics of PZT- and Al2O3-based ceramics, control of the sintering temperature and the dependence of the linear shrinkage on the solid content of the tape-casting films were systematically conducted at first. The sintering density and the interface bonding properties of the prepared composites were then investigated. The results of electrical and mechanical properties of the composite ceramics indicate: By using sintering aids, Al2O3 ceramic could be fully densified and co-fired with PZT ceramic at 1150 °C. Shrinkage matching during sintering was achieved by adjusting the solid contents to 45 vol.% and 65 vol.% for PZT and alumina tape-casting films. In the layered composites, Al2O3 structural ceramic presents an excellent mechanical property with HV hardness of 667, while the PZT functional ceramic presents d33, εr and tanδ of 259 pC/N, 965 and 0.37%, respectively. [ABSTRACT FROM AUTHOR]

The development of high-power piezoelectric ceramics with superior piezoelectric properties and broad temperature usage ranges is vital for the thriving progress of electromechanical applications. However, achieving high piezoelectricity, high mechanical quality factor, and temperature stability often presents a trade-off. In this study, we present an advanced ceramic material with excellent high-power piezoelectric properties and superior temperature stability. The piezoelectric coefficient d 33 reaches 348 pC N−1, the electromechanical coupling factor k p is 54%, the mechanical quality factor Q m is 1501, the dielectric loss tanδ is 0.35%, and the d 33 variation is less than 10% within 25–210 °C in 0.05Pb(Mg1/3Nb2/3)O 3 -0.05Pb(Mn 1/3 Sb 2/3)O 3 -0.9Pb 0.95 Sr 0.05 (Zr 0.48 Ti 0.52)O 3 ceramic. The excellent piezoelectricity is attributed to the enhancement of intrinsic ionic displacement and reversible domains wall motion because of symmetry-conforming short-range distribution of oxygen vacancy, while the high Q m is a result of increased domain size and oxygen vacancy. The outstanding temperature stability is related to the stable non-180°domains structure due to the oxygen vacancy pinning effect. These properties hold great potential for advanced applications, particularly for piezoelectric high-power applications requiring constant d 33 over a broad temperature range. [ABSTRACT FROM AUTHOR]

Temperature scaling of dynamic ferroelectric hysteresis for the morphotropic phase boundary (MPB) compositions in xBiScO3–(1‐x‐y)PbZrO3–yPbTiO3 (xBS–(1‐x‐y)PZ–yPT, 0.018 ≤ x ≤ 0.264) ternary system was systematically investigated. The power‐law relation was obtained for remanent polarization Pr and temperature T, that is, Pr ∝ Tβ. It is interesting to find that the power‐law exponent β could be modulated by BiScO3 content x. With the increase of x from 0.018 to 0.264, β varies from −1.09398 to 2.44147. Transition of β from negative to positive produces in the vicinity of 0.054BS–0.476PZ–0.470PT ceramic. At this composition, the magnitude of β is very close to zero with value of only −0.01567, implying an almost temperature‐independent polarization characteristic of the ceramic. Comparing with the conventional PZT‐based piezoelectric ceramics that usually with negative exponent β, when x > 0.054, the xBS–(1‐x‐y)PZ–yPT ceramics show positive β value, so that the ferroelectric polarization is enhanced with increasing temperature. Such a positive temperature dependence of ferro‐/piezoelectric property makes the ternary system a promising candidate for high‐temperature applications. [ABSTRACT FROM AUTHOR]

We report experimental investigation on the ferroelectricity and electric field-induced strain response in LiNbO 3 -doped 0.94(Bi 0.5 Na 0.5 )TiO 3 -0.06BaTiO 3 (BNT-BT) piezoelectric ceramics. At room temperature, a large strain of 0.6% (at 70 kV/cm) is achieved in the 2.5%-LiNbO 3 -doped BNT-BT, higher than that of commercially-utilized Pb(Zr,Ti)O 3 . The corresponding piezoelectric coefficient d * 33 reaches 857 pm/V, which is high among these of BNT-based ceramics at room temperature. Further study indicates that the superior piezoelectric properties are realized at the ferroelectric-relaxor transition temperature T F-R , which is pushed to room temperature with 2.5% LiNbO 3 doping. This indicates that large electromechanical response can be induced via delicate mixing of the ferroelectric rhombohedral phase and the polar nanoregions (PNRs) relaxor-ferroelectric tetragonal phase. [ABSTRACT FROM AUTHOR]

Piezoelectric ceramics with large energy density coefficient d33· g33 value have been found suitable for piezoelectric energy harvesting applications. In this study, the phase structures and piezoelectric properties of x Pb( Zr0.5 Ti0.5)O3− y Pb( Zn1/3 Nb2/3)O3−(1− x− y) Pb( Ni1/3 Nb2/3) O3 ( x PZT− y PZN−(1− x− y) PNN) ceramic were investigated with systematically varying PZN and PNN components. The ternary phase diagram of PZT− PZN− PNN system was illustrated and the composition region of morphotropic phase boundary (MPB) was determined. Piezoelectric and dielectric measurements verify that the materials in MPB region all present large d33 and d33· g33 values. In particular, very high d33· g33 coefficients of 20162.2 × 10−15 m2/N and 21026.3 × 10−15 m2/N are observed from samples 0.75 PZT−0.15 PZN−0.1 PNN and 0.8 PZT−0.05 PZN−0.15 PNN with compositions located on the rhombohedral phase side near MPB because the dielectric coefficient ε33T/ε0 decreases faster than the d33 coefficient at this side. [ABSTRACT FROM AUTHOR]

Lead-free 0.96(K0.5Na0.5)NbO3-0.04LiTaO3 + x% MgO ceramics with x = 0.00, 0.25, 0.50, 0.75 and 1.00 were prepared by conventional solid-state sintering technique. The effects of MgO on the phase transitional behavior, microstructure, piezoelectric and dielectric properties were investigated. 0.96(K0.5Na0.5)NbO3-0.04LiTaO3 ceramics were chosen because of their high piezoelectric coefficient d33 and electromechanical coupling factor kp. These samples exhibit a polymorphic phase transition from orthorhombic to tetragonal symmetry near the room temperature, which is analogous to the morphtropic phase boundary (MPB). In order to further improve the piezoelectric and dielectric characteristics meanwhile decrease sintering temperature, alkaline earth element Mg had been doped in 0.96(K0.5Na0.5)NbO3-0.04LiTaO3 ceramics. Our results show that the doping of MgO could not only improve the sintering performance but also be effective on promoting the dielectric properties. [ABSTRACT FROM AUTHOR]

The enhanced and reliable high-power performance of x Pb(Mn 1/3 Nb 2/3)O 3 –(1- x)Pb(Zr 0.5 Ti 0.5)O 3 –0.5mol%Co 2 O 3 piezoelectric ceramics (x PMN–(1- x)PZT–Co; x = 0.04–0.10) has been achieved. It is noteworthy that the vibration velocity (υ 0) of the 0.08PMN–0.92PZT–Co ceramic reaches up to 0.9 m/s, which is 2.25 times that of commercial PZT4 ceramics (∼0.4 m/s). The high υ 0 of the 0.08PMN–0.92PZT–Co ceramic is attributed to its excellent electromechanical parameters: d 33 = 405 pC/N, Q m = 1405, and k p = 0.61. The 0.08PMN–0.92PZT–Co ceramic achieves a relatively low high-field tan δ (tan δ = 3.74% at 500 V/mm), thereby suppressing heat generation. Additionally, the significantly high Curie temperature (T c) value of 346 °C for the 0.08PMN–0.92PZT–Co ceramic stabilizes the ferroelectric phase. Therefore, the 0.08PMN–0.92PZT–Co ceramic exhibits long-term reliable high-power performance by maintaining a stable υ 0 of 0.9 m/s and slight temperature rise within 100 min. [ABSTRACT FROM AUTHOR]

Abstract: Pb(Mg1/3Ta2/3)O3–Pb(Mn1/3Sb2/3)O3–Pb(Zr x Ti1−x )O3 quaternary piezoelectric ceramics with different compositions near the morphotropic phase boundary were synthesized using a conventional solid state reaction method. The phases, microstructures, ferroelectric, piezoelectric and dielectric properties of the system were investigated. A transition from rhombohedral to tetragonal phase was observed as the Zr/Ti ratio decreased. The P–E loops presented pinched shapes at low electric fields and the distortions disappeared at high electric fields. The dielectric study revealed a diffuse phase transition behavior in the ceramics. The optimal dielectric and piezoelectric properties ɛ r =817, d 33 =285pC/N, k p =0.55, T C =302°C, tan δ =0.4% and Q m =1600 of the ceramics were obtained at the composition of Zr/Ti=50/50. Vibration velocity at ΔT =20°C was found as high as 0.74m/s for this composition, which was almost 2.5 times as that of the commercial hard PZT ceramics. [ABSTRACT FROM AUTHOR]

The multiferroic (1−x)BiFeO 3 −xBi 0.5 K 0.5 TiO 3 (BFO–xBKT) ceramic was prepared to investigate the dependence of its structural and electrical properties on BKT component. The ceramic processes a rhombohedral phase at 0 ≤ x ≤ 0.3 and a tetragonal phase at 0.5 ≤ x ≤ 1.0 while it owns the coexistence of these two phases at x∼0.4, according to the XRD patterns and the corresponding simulation with the Reitveld method. Specifically, BFO–0.4BKT shows a saturated polarization of 65.8 μC/cm 2 and an enhanced piezoelectric d 33 of 61 pC/N at room temperature which are much larger than those of other ceramics at x = 0–0.7. The dependence of dielectric constant on temperature suggests a strong relaxor characteristic and a high Curie temperature of ∼462 °C. Furthermore, the poled BFO–0.4BKT ceramic shows radial dielectric resonances at 20–300 °C due to the piezoelectric effect. [ABSTRACT FROM AUTHOR]