Artykuły w czasopismach: „Piezoelectric polycrystalline ceramics”

1

Rödel, J., i W. S. Kreher. "Effective properties of polycrystalline piezoelectric ceramics". Le Journal de Physique IV 09, PR9 (wrzesień 1999): Pr9–239—Pr9–247. http://dx.doi.org/10.1051/jp4:1999924.

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Cowen, Benjamin, Christopher Eadie, Jules Lindau i John Mauro. "Template alignment optimization in additively manufactured piezoelectric ceramics". Journal of the Acoustical Society of America 153, nr 3_supplement (1.03.2023): A196. http://dx.doi.org/10.1121/10.0018639.

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Sonar transducer performance is greatly impacted by the microstructural alignment of the ceramics from which they are fabricated. Textured ceramics are a desirable material source for these parts because their deliberately aligned microstructures allow for tailored anisotropic properties that rival those of single crystal ceramics, but they also maintain the mechanical robustness and bulk manufacturability of polycrystalline ceramics. Current methods for manufacturing textured ceramics, e.g., tape casting, severely limit design freedom and require excess material waste, and so the advantage of texturing has not been fully realized. This study is focused on the enhancement of direct ink writing of textured ceramics. Direct ink writing is an additive manufacturing (AM) technique that enhances design freedom on a macro and micro scale and reduces waste by producing near-net shape textured ceramics. However, shear stresses during the AM process affect the microstructural alignment of the ceramic in an extremely complex manner that is difficult to control directly. This study first validates a novel alignment metric, derived from a computational fluid dynamics model that simulates the printing process, against real-world data. Then, an optimization algorithm is used to maximize alignment with respect to the nozzle geometry.

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Islam, Rashed Adnan, i Shashank Priya. "Realization of high-energy density polycrystalline piezoelectric ceramics". Applied Physics Letters 88, nr 3 (16.01.2006): 032903. http://dx.doi.org/10.1063/1.2166201.

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Tan, Xiaoli, Hui He i Jian-Ku Shang. "In situ Transmission Electron Microscopy Studies of Electric-field-induced Phenomena in Ferroelectrics". Journal of Materials Research 20, nr 7 (1.07.2005): 1641–53. http://dx.doi.org/10.1557/jmr.2005.0213.

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High electric fields were delivered to specimens during imaging in the transmission electron microscopy (TEM) chamber to reveal details of electric field-induced phenomena in ferroelectric oxides. These include the polarization switching in nanometer-sized ferroelectric domains and the grain boundary cavitation in a commercial lead zirconate titanate (PZT) polycrystalline ceramic, the domain wall fracture in a Pb(Mg1/3Nb2/3)O3–PbTiO3 single crystal, and the transformation of incommensurate modulations in Pb0.99Nb0.02[(Zr1−xSnx)1−yTiy]0.98O3 (PZST100x/100y/2) polycrystalline ceramics. In the PZT ceramic, a cavitation process was uncovered for the electric field-induced intergranular fracture. In the ferroelectric single crystal, a preexisting crack was observed to deflect and to follow a 90° domain wall, indicating the presence of severe incompatible piezoelectric strains at thedomain wall. In the antiferroelectric PZST ceramics, the electric field-induced antiferroelectric-to-ferroelectric phase transformation was accompanied with the disappearance of incommensurate modulations.

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Liu, Wenfeng, Lu Cheng i Shengtao Li. "Prospective of (BaCa)(ZrTi)O3 Lead-free Piezoelectric Ceramics". Crystals 9, nr 3 (26.03.2019): 179. http://dx.doi.org/10.3390/cryst9030179.

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Piezoelectric ceramics is a functional material that can convert mechanical energy into electrical energy and vice versa. It can find wide applications ranging from our daily life to high-end techniques and dominates a billion-dollar market. For half a century, the working horse of the field has been the polycrystalline PbZr1−xTixO3 (PZT), which is now globally resisted for containing the toxic element lead. In 2009, our group discovered a non-Pb piezoelectric material, (BaCa)(ZrTi)O3 ceramics (BZT-BCT), which exhibits an ultrahigh piezoelectric coefficient d33 of 560–620 pC/N. This result brought extensive interest in the research field and important consequences for the piezoelectric industry that has relied on PZT. In the present paper, we review the recent progress, both experimental and theoretical, in the BZT-BCT ceramics.

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Choi, Minkyu, Yoonsang Park, Hossein Daneshpajooh, Timo Scholehwar, Eberhard Hennig i Kenji Uchino. "Determination of anisotropic intensive piezoelectric loss in polycrystalline ceramics". Ceramics International 47, nr 11 (czerwiec 2021): 16309–15. http://dx.doi.org/10.1016/j.ceramint.2021.02.210.

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Utzinger, Johannes, Paul Steinmann i Andreas Menzel. "Computational modelling of microcracking effects in polycrystalline piezoelectric ceramics". GAMM-Mitteilungen 31, nr 2 (grudzień 2008): 151–65. http://dx.doi.org/10.1002/gamm.200890008.

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Nicolai, Michael, Stefan Uhlig, Andreas Schönecker i Alexander Michaelis. "Experimental Investigation of Non-Linear Behaviour of PZT Piezoceramics at Low Temperatures". Advances in Science and Technology 56 (wrzesień 2008): 105–10. http://dx.doi.org/10.4028/www.scientific.net/ast.56.105.

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The complex, non-linear, irreversible, hysteretic behaviour of polycrystalline ferroelectric materials is the result of domain wall motion and correlates with the phase composition of the ceramic. This paper reports on our investigation of the ferroelectric polarization of PZT ceramics in dependence of temperature in the range between -175 and 150°C. We compare five commercial piezoelectric materials used in actuator applications. The obtained data, derived correlations, and material functions are very helpful for understanding the material properties in practical applications and give input values for temperature depended numerical hysteretic models [1].

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LEE, Ho-Yong. "“Generation III” Piezoelectric Single Crystals Developed by Solid-State Single Crystal Growth Method". Ceramist 24, nr 3 (30.09.2021): 273–85. http://dx.doi.org/10.31613/ceramist.2021.24.3.07.

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Crystallographically engineered Relaxor-PT single crystals, specifically PMN-PT (Generation I) and PIN-PMN-PT/PMN-PZT (Generation II), offer much higher piezoelectric and electromechanical coupling coefficients (d33>1,500 pC/N, k33>0.9), when compared to polycrystalline PZT-5H ceramics (d33>600 pC/N, k33>0.75). Recently Ceracomp Co., Ltd. (www.ceracomp.com) has developed the solid-state single crystal growth (SSCG) technique and successfully fabricated Gen III PMN-PZT single crystals modified with acceptors or donors. The piezoelectric constants (d33) of (001) Gen III PMN-PZT single crystals were measured to be higher than 4,000 pC/N and thus about two times higher than those of PMN-PT/PZN-PT (Gen I) and PIN-PMN-PT/PMN-PZT (Gen II) single crystals. The Gen III PMN-PZT single crystals have been firstly applied to single crystal-epoxy composites, ultrasonic transducers, piezoelectric sensors, and piezoelectric actuators. In this paper we introduce the development of Gen III PMN-PZT single crystals, piezoelectric composites and multilayer single crystal actuators.

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Zhao, H. W., Y. L. Li, R. J. Zhao i Z. Q. Li. "Effect of sintering temperature on the structure and electrical properties of KNNS-0.03BNZ ceramics". Digest Journal of Nanomaterials and Biostructures 18, nr 3 (20.07.2023): 813–19. http://dx.doi.org/10.15251/djnb.2023.183.813.

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(K0.48Na0.52)NbO3-0.03Bi0.5Na0.5ZrO3 (KNNS-0.03BNZ) ceramics were prepared doped with 3 mol% Bi0.5Na0.5ZrO3 (BNZ), and the effect of sintering temperature on dielectric and piezoelectric properties of KNNS-0.03BNZ was also investigated. KNNS-0.03BNZ ceramics at all sintering temperatures exhibit a single perovskite structure, and the change of sintering temperature has no significant effect on the phase composition of KNNS 0.03BNZ ceramics. The Raman shifts of the ν1 and ν5 vibration modes have irregular changes in all sintering temperature ranges, indicating that there are polycrystalline phases coexisting in this region. With the change of sintering temperature, Tc slightly shifts to the high temperature direction, and TR-T slightly shifts to the high temperature direction, dielectric constant εr continuously increases, while dielectric loss tanδ firstly decreasing and then increasing. Thanks to the presence of a small amount of liquid phase in the ceramics sintered at 1160 ℃, piezoelectric coefficient d33 reaches 280 pC/N.

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Lewis, D. J., D. Gupta, M. R. Notis i Yoshihiko Imanaka. "Diffusion of ^110mAg Tracer in Polycrystalline Piezoelectric Ceramics". Defect and Diffusion Forum 194-199 (kwiecień 2001): 1009–16. http://dx.doi.org/10.4028/www.scientific.net/ddf.194-199.1009.

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Lisińska-Czekaj, Agata, Dionizy Czekaj, Barbara Garbarz-Glos, Wojciech Bąk, Temesgen Tadeyos Zate i Jae-Ho Jeon. "Dielectric Spectroscopy Studies and Modelling of Piezoelectric Properties of Multiferroic Ceramics". Applied Sciences 13, nr 12 (16.06.2023): 7193. http://dx.doi.org/10.3390/app13127193.

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Compounds and solid solutions of bismuth ferrite (BiFeO3)—barium titanate (BaTiO3) system are of great scientific and engineering interest as multiferroic and potential high-temperature lead-free piezoelectric materials. In the present paper, the results of research on the synthesis and characterisation of 0.67Bi1.02FeO3–0.33BaTiO3 (67BFBT) ceramics in terms of crystal structure and dielectric and piezoelectric properties are reported. It was found that the produced 67BFBT ceramics were characterised by a tetragonal crystal structure described by the P4mm space group, an average crystallite size <D> ≈ 80 nm, and an average strain <ε> = 0.01%. Broad-band dielectric spectroscopy (BBDS) was employed to characterise the dielectric response of polycrystalline ceramics. The frequency range from ν = 10−1 Hz to ν = 105 Hz was used to characterise the influence of the electric field strength on dielectric response of the ceramic sample at room temperature. The dielectric spectra were checked for consistency with the Kramers–Kronig test, and the high quality of the measurements were confirmed. The electric equivalent circuit method was used to fit the dielectric spectra within the frequency range that corresponded to the occurrence of the resonant spectra of the radial mode for thin disk sample, i.e., from ν = 105 Hz to ν = 107 Hz and the temperature range from T = −20 °C to T = 50 °C. The electric equivalent circuit [RsCPE1([L1R1C1]C0)] was used, and good fitting quality was reached. The relevant calculations were performed, and it was found that the piezoelectric charge coefficient exhibited a value of d31 = 35 pC/N and the planar coupling factor was kp = 31% at room temperature. Analysis of impedance spectra performed in terms of circumferential magnetic field made it possible to establish an influence of magnetic field on piezoelectric parameters of 67BFBT multiferroic ceramics. Additionally, the “magnetic” tunability of the modulus of the complex dielectric permittivity makes 67BFBT a sensing material with vast potential.

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Delibas, Bülent, Arunachalakasi Arockiarajan i Wolfgang Seemann. "A nonlinear model of piezoelectric polycrystalline ceramics under quasi-static electromechanical loading". Journal of Materials Science: Materials in Electronics 16, nr 8 (sierpień 2005): 507–15. http://dx.doi.org/10.1007/s10854-005-2725-2.

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Chen, Chao-Ting, Shun-Chiu Lin, Urška Trstenjak, Matjaž Spreitzer i Wen-Jong Wu. "Comparison of Metal-Based PZT and PMN–PT Energy Harvesters Fabricated by Aerosol Deposition Method". Sensors 21, nr 14 (12.07.2021): 4747. http://dx.doi.org/10.3390/s21144747.

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In this study, polycrystalline lead magnesium niobate–lead titanate (PMN–PT) was explored as an alternative piezoelectric material, with a higher power density for energy harvesting (EH), and comprehensively compared to the widely used polycrystalline lead zirconate titanate (PZT). First, the size distribution and piezoelectric properties of PZT and PMN–PT raw powders and ceramics were compared. Thereafter, both materials were deposited on stainless-steel substrates as 10 μm thick films using the aerosol deposition method. The films were processed as {3–1}-mode cantilever-type EH devices using microelectromechanical systems. The films with different annealing temperatures were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and dielectric behavior measurements. Furthermore, the mechanical and electrical properties of PMN–PT- and PZT-based devices were measured and compared. The PMN–PT-based devices showed a higher Young’s modulus and lower damping ratio. Owing to their higher figure of merit and lower piezoelectric voltage constant, they showed a higher power and lower voltage than the PZT-based devices. Finally, when poly-PMN–PT material was the active layer, the output power was enhanced by 26% at the 0.5 g acceleration level. Thus, these devices exhibited promising properties, meeting the high current and low voltage requirements in integrated circuit designs.

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Ivashov, I. V., i A. S. Semenov. "Influence of crack face boundary conditions on the fracture of polycrystalline piezoelectric ceramics". Magazine of Civil Engineering 51, nr 07 (listopad 2014): 5–15. http://dx.doi.org/10.5862/mce.51.1.

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Lewis, Daniel J., Devendra Gupta, Michael R. Notis i Yoshihiko Imanaka. "Diffusion of 110mAg Tracer in Polycrystalline and Single-Crystal Lead-Containing Piezoelectric Ceramics". Journal of the American Ceramic Society 84, nr 8 (20.12.2004): 1777–84. http://dx.doi.org/10.1111/j.1151-2916.2001.tb00914.x.

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Shekhan, Husain N., Erkan A. Gurdal, Lalitha Ganapatibhotla, Janna K. Maranas, Ron Staut i Kenji Uchino. "Thermal Conductivities of PZT Piezoelectric Ceramics under Different Electrical Boundary Conditions". Insight - Material Science 3, nr 1 (17.03.2020): 10. http://dx.doi.org/10.18282/ims.v3i1.301.

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Physical properties of polycrystalline lead-zirconate-titanate (PZT) changes according to electrical boundary conditions and poling. This paper reports the thermal properties of poled and unpoled PZT's in the poling direction for open circuit and short circuit conditions. The authors found that the short-circuit condition exhibited the largest thermal conductivity than the open-circuit condition. In the relationship between these two thermal properties, the authors propose the "electrothermal" coupling factor kκ33, which is similar to the electromechanical coupling factor k33 relating the elastic compliances under short- and open-circuit conditions. On the other hand, the thermal conductivity of the unpoled specimen exhibits the lowest thermal conductivity, in comparison with the poled specimens, which suggests the importance of phonon mode scattering on the thermal conductivity with respect to elastic compliance.

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Uršič, Hana, i Uroš Prah. "Investigations of ferroelectric polycrystalline bulks and thick films using piezoresponse force microscopy". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 475, nr 2223 (marzec 2019): 20180782. http://dx.doi.org/10.1098/rspa.2018.0782.

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In recent years, ferroelectric/piezoelectric polycrystalline bulks and thick films have been extensively studied for different applications, such as sensors, actuators, transducers and caloric devices. In the majority of these applications, the electric field is applied to the working element in order to induce an electromechanical response, which is a complex phenomenon with several origins. Among them is the field-induced movement of domain walls, which is nowadays extensively studied using piezoresponse force microscopy (PFM), a technique derived from atomic force microscopy. PFM is based on the detection of the local converse piezoelectric effect in the sample; it is one of the most frequently applied methods for the characterization of the ferroelectric domain structure due to the simplicity of the sample preparation, its non-destructive nature and its relatively high imaging resolution. In this review, we focus on the PFM analysis of ferroelectric bulk ceramics and thick films. The core of the paper is divided into four sections: (i) introduction; (ii) the preparation of the samples prior to the PFM investigation; (iii) this is followed by reviews of the domain structures in polycrystalline bulks; and (iv) thick films.

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Foschini, Cesar, Bruno Hangai, Paulo Ortega, Elson Longo, Mário Cilense i Alexandre Simões. "Evidence of ferroelectric behaviour in CaCu3Ti4O12 thin films deposited by RF-sputtering". Processing and Application of Ceramics 13, nr 3 (2019): 219–28. http://dx.doi.org/10.2298/pac1903219f.

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The origin of abnormal ferroelectric and unusual piezoelectricity in the polycrystalline CaCu3Ti4O12 (CCTO) thin films deposited by RF-sputtering on Pt/Ti/SiO2/Si (100) substrates was explored. The CCTO thin films, deposited at room temperature followed by annealing at 600?C for 2 h in a conventional furnace, have a cubic structure with lattice parameter a = 7.379 ? 0.001 ? and without any secondary phases. No polarization loss up to 1010 switching cycles, with a switched polarization ?P of 30 ?C/cm2 measured at 400 kV/cm was evidenced. The piezoelectric coefficient investigated by piezoresponse force microscopy (PFM) was approximately 9.0 pm/V. This may be the very first example of exploring the origin of ferroelectric behaviour for a material that possesses space charge polarization with highly resistive grain boundaries in the polycrystalline state.

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Hinterstein, Manuel, Michael Knapp, Markus Hölzel, Wook Jo, Antonio Cervellino, Helmut Ehrenberg i Hartmut Fuess. "Field-induced phase transition in Bi1/2Na1/2TiO3-based lead-free piezoelectric ceramics". Journal of Applied Crystallography 43, nr 6 (13.10.2010): 1314–21. http://dx.doi.org/10.1107/s0021889810038264.

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The origin of the electric field-induced strain in the polycrystalline ceramic 0.92Bi1/2Na1/2TiO3–0.06BaTiO3–0.02K1/2Na1/2NbO3was investigated usingin situhigh-resolution X-ray and neutron diffraction techniques. The initially existing tetragonal phase with pseudocubic lattice undergoes a reversible phase transition to a significantly distorted rhombohedral phase under electric field, accompanied by a change in the oxygen octahedral tilting froma0a0c+toa−a−a−and in the tilting angle. The polarization values for the tetragonal and rhombohedral phases were calculated based on the structural information from Rietveld refinements. The large recoverable electric field-induced strain is a consequence of a reversible electric field-induced phase transition from an almost nonpolar tetragonal phase to a ferroelectrically active rhombohedral phase.

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Fan, Qiaolan, Weidong Zeng, Changrong Zhou, Zhenyong Cen, Changlai Yuan, Jianrong Xiao i Jiafeng Ma. "Effect of Reoriented Nanodomains on Crystal Structure and Piezoelectric Properties of Polycrystalline Ferroelectric Ceramics". Journal of Electronic Materials 44, nr 10 (3.06.2015): 3843–48. http://dx.doi.org/10.1007/s11664-015-3795-4.

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Tang, Hua, Shujun Zhang, Yujun Feng, Fei Li i Thomas R. Shrout. "Piezoelectric Property and Strain Behavior of Pb(Yb0.5 Nb0.5 )O3 -PbHfO3 -PbTiO3 Polycrystalline Ceramics". Journal of the American Ceramic Society 96, nr 9 (20.05.2013): 2857–63. http://dx.doi.org/10.1111/jace.12389.

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Zhang, Youfeng, Yali Yao i Shasha He. "Sinterability and Dielectric Properties of LiTaO3-Based Ceramics with Addition of CoO". Materials 13, nr 7 (25.03.2020): 1506. http://dx.doi.org/10.3390/ma13071506.

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Lithium tantalite (LiTaO3) is a common piezoelectric and ferroelectric crystal, but the LiTaO3 polycrystalline ceramics have rarely been reported, and their refractory character presents difficulties in their fabrication. In this study, LiTaO3-based ceramics with different amounts of CoO were prepared by pressureless sintering at 1250 °C, and the effects of the amount of sintering aid on the sinterability, microstructure, and dielectric properties of the ceramics were investigated. The relative densities of the LiTaO3-based ceramics were significantly improved by the addition of CoO powder. The LiTaO3-based ceramics achieved the highest relative density (89.4%) and obtained a well-grained microstructure when the added amount of CoO was 5 wt.%. Only the LiTaO3 phase in the ceramics was observed, indicating that the ions Co diffused into the LiTaO3 lattices and mainly existed in two forms: Co2+ and Co3+. The effects of the added amount of CoO on the dielectric properties of the LiTaO3-based ceramics were studied thoroughly. Consequently, the dielectric constant was enhanced, and the dielectric loss decreased in the LiTaO3-based ceramics with the addition of CoO. The optimal value was obtained at 5 wt.% of CoO-added LiTaO3-based ceramics.

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Martin, Alexander, Neamul H. Khansur, Udo Eckstein, Kevin Riess, Ken-ichi Kakimoto i Kyle G. Webber. "High temperature piezoelectric response of polycrystalline Li-doped (K,Na)NbO3 ceramics under compressive stress". Journal of Applied Physics 127, nr 11 (21.03.2020): 114101. http://dx.doi.org/10.1063/1.5134554.

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SAMBASIVA RAO, K., HAILEEYESUS WORKINEH, A. SWATHI i B. S. KALYANI. "SYNTHESIS, PIEZOELECTRIC, DIELECTRIC AND CONDUCTIVITY STUDIES ON Dy2O3 SUBSTITUTED (Bi0.94Na0.94)0.5Ba0.06TiO3 CERAMICS". Journal of Advanced Dielectrics 01, nr 04 (październik 2011): 455–64. http://dx.doi.org/10.1142/s2010135x11000513.

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Polycrystalline ( Bi 0.94-x Dy x Na 0.94)0.5 Ba 0.06 TiO 3 ceramics (x = 0, 0.04, and 0.08, designated as BNBT6, BNBT6: 4Dy and BNBT6: 8Dy, respectively) were prepared by conventional high temperature sintering method. The X-ray diffraction patterns show pure perovskite structure with no secondary phases. Lattice parameters and unit cell volumes have decreased due to Dy2O3 substitution. SEM micrographs revealed denser samples (ρrel > 97%) with uniformly distributed grain sizes. The room temperature piezoelectric properties of Dy2O3 substituted sample at x = 0.04 were relatively higher: d33 = 147 pC/N, k p = 28% and Q m = 128. The samples exhibited infinitesimal change in thickness (≈ 15 nm) to an applied voltage of 100 V, which could be utilized in actuator applications. Relaxor behavior and broad dielectric maxima with diffuse phase transition were observed. The value of RT dielectric constant has increased while dielectric loss was decreased due to Dy2O3 substitution. Conductivity in the materials obeys Jonscher's universal power law. The conductivity in the low frequency region is associated with short range translational hopping while it is associated with the reorientational hopping in the high frequency region. The charge carrier concentration term remained constant over the entire temperature range of (30–500°C).

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AHN, CHEOL-WOO, CHEE-SUNG PARK i SHASHANK PRIYA. "SINTERED COMPOSITE FOR LOW TEMPERATURE COEFFICIENT OF PIEZOELECTRIC PROPERTY IN KNN BASED LEAD-FREE CERAMICS". Functional Materials Letters 03, nr 01 (marzec 2010): 35–39. http://dx.doi.org/10.1142/s1793604710000907.

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We propose the design and synthesis of a polycrystalline sintered composite microstructure that leads to improved stability of piezoelectric response as a function of temperature in ( K , Na ) NbO 3 (KNN) based ceramics. The microstructure consists of matrix and island both of which have different composition and surface area. The matrix had much larger surface area and smaller orthorhombic to tetragonal transition temperature (T O-T ) than island. The composition corresponding to 0.99( K 0.48 Na 0.48 Li 0.04)( Nb 0.98 Sb 0.02) O 3-0.01 BaTiO 3 ( KNLNS-BT , T O-T ~ 33° C ) was selected as matrix while ( K 0.5 Na 0.5) NbO 3 ( KNN , T O-T ~ 206° C) was selected as island. The results show the flat electromechanical coupling factor from room temperature until ~ 300°C.

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Muñoz-Saldaña, J., M. J. Hoffmann i G. A. Schneider. "Ferroelectric domains in coarse-grained lead zirconate titanate ceramics characterized by scanning force microscopy". Journal of Materials Research 18, nr 8 (sierpień 2003): 1777–86. http://dx.doi.org/10.1557/jmr.2003.0247.

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Ferroelectric domain configurations in silver- and lanthanum-doped lead zirconate titanate (PZT) ceramics were characterized by scanning force microscopy using contact as well as piezoelectric response force [i.e., piezoelectric force microscopy (PFM)] modes. Coarse crystallites of hard and soft PZT ceramics (12 μm in Ag-PZT and 30 μm in La-PZT average grain size, respectively) with surface oriented in the {001} planes were chosen to characterize the domain configuration. Results show the conventional right-angled domain structures, which correspond to the {110} twin-related 90° and 180° domains of homogeneous width from 50 to 150 nm. The ability of PFM to image the orientation of pure in-plane arrays of domains (containing 90°-aa- and 180°-aa-types of domain boundaries) is highlighted, and a more detailed notation for in-plane domains is proposed. In addition to such periodical domain arrays, other ordered domains were found, having a misfit of 26° with respect to the{110} domain walls and the {100} surface. This array of domain walls could not be predicted with a geometrical analysis of the intersection of domain walls at the surface according to the conventional spatial array of {110} crystallographic planes. It could be explained only with {210} planes being the domain walls. The reason for this unconventional domain configuration is explained with the clamped conditions of the investigated crystallites in the polycrystalline material.

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Kholkin, A. L., I. K. Bdikin, D. A. Kiselev, V. V. Shvartsman i S. H. Kim. "Nanoscale characterization of polycrystalline ferroelectric materials for piezoelectric applications". Journal of Electroceramics 19, nr 1 (6.03.2007): 83–96. http://dx.doi.org/10.1007/s10832-007-9045-2.

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Le, Fisher i Moon. "Effect of Composition on the Growth of Single Crystals of (1−x)(Na1/2Bi1/2)TiO3-xSrTiO3 by Solid State Crystal Growth". Materials 12, nr 15 (24.07.2019): 2357. http://dx.doi.org/10.3390/ma12152357.

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The (1−x)(Na1/2Bi1/2)TiO3-xSrTiO3 (NBT-100xST) system is a possible lead-free candidate for actuator applications because of its excellent strain vs. electric field behaviour. Use of single crystals instead of polycrystalline ceramics may lead to further improvement in piezoelectric properties but work on single crystal growth in this system is limited. In particular, the effect of composition on single crystal growth has yet to be studied. In this work, single crystals of (NBT-100xST) with x = 0.00, 0.05, 0.10 and 0.20 were grown using the method of Solid State Crystal Growth. [001]-oriented SrTiO3 single crystal seeds were embedded in (NBT-100xST) ceramic powder, which was then pressed to form pellets and sintered at 1200 °C for 5 min–50 h. Single crystal growth rate, matrix grain growth rate and sample microstructure were examined using scanning and transmission electron microscopy. The results indicate that the highest single crystal growth rate was obtained at x = 0.20. The mixed control theory of grain growth is used to explain the single crystal and matrix grain growth behaviour.

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DU, Xiao-Hong, Qing-Ming WANG, Uma BELEGUNDU i Kenji UCHINO. "Piezoelectric Property Enhancement in Polycrystalline Lead Zirconate Titanate by Changing Cutting Angle." Journal of the Ceramic Society of Japan 107, nr 1242 (1999): 190–91. http://dx.doi.org/10.2109/jcersj.107.190.

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Long, Changbai, Wei Ren, Kun Zheng i Huiqing Fan. "Ultrahigh-temperature piezoelectric polycrystalline ceramics: dramatically enhanced ferroelectricity, piezoelectricity and electrical resistivity in Ca1−3xBi2+3xNb2−xMnxO9". Materials Research Letters 8, nr 4 (14.02.2020): 165–72. http://dx.doi.org/10.1080/21663831.2020.1725676.

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32

Kuzenko, D. V. "Critical temperature below the Curie temperature of ferroelectric ceramics PZT". Journal of Advanced Dielectrics 11, nr 01 (luty 2021): 2150006. http://dx.doi.org/10.1142/s2010135x21500065.

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The article presents the results of research the pre-transitional features of the behavior of solid solutions based on lead zirconate-titanate. The presence of a “special” critical temperature [Formula: see text] on the temperature dependences of the permittivity [Formula: see text] and the remanent polarization [Formula: see text], preceding the temperature of the paraelectric phase transition at the Curie temperature [Formula: see text], is noted. In the temperature range [Formula: see text] < [Formula: see text], the [Formula: see text] dependence obeys a power law. In the temperature range [Formula: see text]<[Formula: see text]<[Formula: see text], this law is not fulfilled. The results of X-ray experiments make it possible to associate this behavior with reversible disordering at [Formula: see text]<[Formula: see text] of an ordered domain structure formed during the polarization of piezoelectric ceramics and with its irreversible disordering in the temperature range [Formula: see text]<[Formula: see text]<[Formula: see text]. This is due to the appearance of internal mechanical stresses in a polycrystalline ferroelectric due to irreversible depolarization of the samples at temperatures [Formula: see text]<[Formula: see text]<[Formula: see text].

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33

Demczyk, B. G. "In situ transmission electron microscopy study of the paraelectric to ferroelectric (cubic to tetragonal) phase transformation in lanthanum-modified lead titanate ceramics". Proceedings, annual meeting, Electron Microscopy Society of America 45 (sierpień 1987): 172–73. http://dx.doi.org/10.1017/s0424820100125798.

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Lead titanate (PbTiO3) forms the ferroelectric end of the ferroelectric-antiferroelectric solid solution series PbTiO3-PbZrO3 (PZT), which is of considerable interest in various piezoelectric applications. Above the Curie point (TC), the material is cubic (paraelectric), point group m3m. Below this temperature transformation occurs to the tetragonal (ferroelectric) phase, point group 4mm. The strain generated in this transformation is relieved via the formation of twin-related structural (ferroelectric) domains. Lanthanum is added to polycrystalline lead titanate to aid in the poling operation (alignment of electric dipoles in individual grains via the application of a large electric field), through a reduction of the c/a ratio in the tetragonal phase. This transformation has been observed in this material in-situ via transmission electron microscopy (TEM).

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34

Narita, Fumio, Yang Zhenjun i Kotaro Mori. "Phase field simulation of temperature dependent dielectric and piezoelectric properties in BaTiO₃ Ceramics polycrystalline ceramics: potentials of temperature energy harvesting". Proceedings of The Computational Mechanics Conference 2017.30 (2017): 051. http://dx.doi.org/10.1299/jsmecmd.2017.30.051.

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35

Dunn, Martin L. "Effects of grain shape anisotropy, porosity, and microcracks on the elastic and dielectric constants of polycrystalline piezoelectric ceramics". Journal of Applied Physics 78, nr 3 (sierpień 1995): 1533–41. http://dx.doi.org/10.1063/1.360246.

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36

Pertsev, N. A., A. G. Zembilgotov i R. Waser. "Aggregate linear properties of ferroelectric ceramics and polycrystalline thin films: Calculation by the method of effective piezoelectric medium". Journal of Applied Physics 84, nr 3 (sierpień 1998): 1524–29. http://dx.doi.org/10.1063/1.368218.

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37

Li, Fei, Shujun Zhang, Zhuo Xu, Xiaoyong Wei, Jun Luo i Thomas R. Shrout. "Piezoelectric activity of relaxor-PbTiO3 based single crystals and polycrystalline ceramics at cryogenic temperatures: Intrinsic and extrinsic contributions". Applied Physics Letters 96, nr 19 (10.05.2010): 192903. http://dx.doi.org/10.1063/1.3430059.

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38

Andryushina, Inna, Anatoliy Pavlenko, Sergey Zinchenko, Konstantin Andryushin, Lidiya Shilkina, Ekaterina Glazunova, Alexandr Nagaenko, Daniil Stryukov, Hizir Sadykov i Larisa Reznichenko. "Obtaining, structure, microstructure and dielectric characteristics of ceramics and thin films of ferro-piezoelectric materials based on the PZT system". Journal of Advanced Dielectrics 10, nr 01n02 (luty 2020): 2060003. http://dx.doi.org/10.1142/s2010135x20600036.

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This paper presents the results of studies of the structure, microstructure, dependences of the piezoelectric properties on the electric field (dielectric hysteresis loops, reversible nonlinearity, deformation characteristics) and dielectric properties of the ceramic material PCR-13 (based on the PZT system) in the temperature range 300–900[Formula: see text]K and frequencies of an alternating electric field ([Formula: see text]) Hz. The character of the obtained dependences made it possible to attribute PCR-13 to ferro-hard materials. Using the HF cathodic sputtering method, PCR-13 thin films were fabricated on Si (001) substrates. It is shown that they are polycrystalline textured, while in comparison with bulk material, the film contains tensile stresses of the unit cell in the plane of the substrate and compresses in the perpendicular direction with the value [Formula: see text]. The capacitance-voltage characteristics of the Al/PCR-13/Si/Al heterostructure were studied. The reasons for the revealed patterns are discussed.

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39

Benedetti, Ivano, Vincenzo Gulizzi i Alberto Milazzo. "A Microstructural Model for Micro-Cracking in Piezoceramics". Key Engineering Materials 774 (sierpień 2018): 479–85. http://dx.doi.org/10.4028/www.scientific.net/kem.774.479.

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Piezoelectric ceramics are employed in several applications for their capability to couple mechanical and electrical fields, which can be advantageously exploited for the implementation of smart functionalities. The electromechanical coupling, which can be employed for fast accurate micro-positioning devices, makes such materials suitable for application in micro electro-mechanical systems (MEMS). However, due to their brittleness, piezoceramics can develop damage leading to initiation of micro-cracks, affecting the performance of the material in general and the micro-devices in particular. For such reasons, the development of accurate and robust numerical tools is an important asset for the design of such systems. The most popular numerical method for the analysis of micro-mechanical multi-physics problems, still in a continuum mechanics setting, is the Finite Element Method (FEM). Here we propose an alternative integral formulation for the grain-scale analysis of degradation and failure in polycrystalline piezoceramics. The formulation is developed for 3D aggregates and inter-granular failure is modelled through generalised cohesive laws.

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40

Hossain, Mohammad J., Zhiyang Wang, Neamul H. Khansur, Justin A. Kimpton, Jette Oddershede i John E. Daniels. "The effect of inter-granular constraints on the response of polycrystalline piezoelectric ceramics at the surface and in the bulk". Applied Physics Letters 109, nr 9 (29.08.2016): 092905. http://dx.doi.org/10.1063/1.4962125.

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41

Huangfu, Geng, Jianwei Chen, Jie Jiao, Haosu Luo i Yiping Guo. "Domain evolution and coercive field reduction in rhombohedral (Na_0.5Bi_0.5)TiO₃-based crystals by alternating electric field". Applied Physics Letters 122, nr 6 (6.02.2023): 062902. http://dx.doi.org/10.1063/5.0139594.

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(Na0.5Bi0.5)TiO3 (NBT)-based materials have been widely studied for their large electric-field-induced strains. However, a high coercive field ( Ec) has long hindered the applications of NBT-based materials. Here, we propose a simple method to significantly reduce the Ec of rhombohedral NBT-based crystals through domain engineering. By applying an alternating current (AC) electric field along the [001] direction, the Ec of Mn-doped (Na0.485K0.015Bi0.5)TiO3 single crystal can be reduced from 70 to 20 kV/cm after about 25 cycles without sacrificing the ferroelectric polarization. Meanwhile, the piezoelectric coefficient d33 and the optical transparency of the crystals are also enhanced compared with those after direct-current electric field poling. The domain structure characterization shows that the AC cycles can form a laminar domain configuration, in which the 109° domain walls are parallel to (001) planes. It is demonstrated that in the laminar domain configuration, almost only 71° polarization switching occurs when the external electric field is reversed. The required energy for polarization reversal is significantly lower than that of the “4R” domain configuration; thus, the Ec is reduced greatly. The low Ec is maintained after depolarization at 250 °C, evidencing good thermal stability of the laminar domain configuration. Furthermore, this method is also applicable to other rhombohedral single crystals and may be applied to [001]-textured polycrystalline ceramics in the future; thus, it may indeed benefit the practical applications of NBT-based piezoelectric devices.

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42

Skaliukh, A. S. "Finite-element Modeling Irreversible Polarization Process of Ferroelectric Ceramics". Mathematics and Mathematical Modeling, nr 5 (12.11.2018): 1–16. http://dx.doi.org/10.24108/mathm.0518.0000145.

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A finite-element model developed for quasi-static processes describes irreversible processes of deformation and polarization occurring in polycrystalline ferroelectric media due to the effect of intense electric fields and mechanical loads. The paper presents external parameters such as strain and polarization as a sum of residual and reversible parts. Using the incremental theory, the virtual work law, and the constitutive relations for reversible and irreversible components, a system of linear algebraic equations was built for the increments of nodal values of the main variables, namely the displacement vector and the electric potential, during the transition from one equilibrium state to another.The constructed constitutive relations connect the reversible parts of the strain and polarization with the stresses and the electric field in the form of linear tensor equations. It is shown that the physical characteristics depend on the residual parameters so that the coefficients of elastic compliance and dielectric constant linearly depend on the principal values of residual strain, and the piezoelectric modules depend linearly on the module of residual polarization. The constitutive relations for the increments of the residual parameters are determined as element values for each finite element from the equations in differentials. Ultimately, the task is reduced to a system of linear algebraic equations, the matrix and right sides of which depend on the residual parameters and are determined at each equilibrium state. As a result, the non-linearity of the problem is replaced by solving a sequence of linear problems until the external loads reach their final values.The model is implanted into a finite-element complex, which allows us to determine the fields of residual strain and polarization, the physical characteristics of a partially polarized body, and local anisotropy for the case of complete and partial polarization.

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43

Oh, Hyun-Taek, Hyun-Jae Joo, Moon-Chan Kim i Ho-Yong Lee. "Effect of Mn on Dielectric and Piezoelectric Properties of 71PMN-29PT [71Pb(Mg1/3Nb2/3)O3-29PbTiO3] Single Crystals and Polycrystalline Ceramics". Journal of the Korean Ceramic Society 55, nr 2 (31.03.2018): 166–73. http://dx.doi.org/10.4191/kcers.2018.55.2.04.

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Dunn, P. E., i S. H. Carr. "A Historical Perspective on the Occurrence of Piezoelectricity in Materials". MRS Bulletin 14, nr 2 (luty 1989): 22–31. http://dx.doi.org/10.1557/s0883769400063405.

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This article provides an overview of the piezoelectric effect in all the classes of materials in which it is found to occur. This includes select materials from the categories of naturally occurring single crystals, polycrystalline ceramics, and semicrystalline polymers. Throughout this development, an attempt is made to point out the common factor for the piezoelectric effect in all these materials, namely, the presence of dipolar moieties, whose orientation brings about a net polarization in the material as a whole.The applications of each of these classes of materials are covered briefly. Each such application has a specific value based on the aggregate properties of the material as a whole, making each material complementary rather than competitive in device applications.Brief mention is made of the mathematics and geometry of the piezoelectric effect in order to define the piezoelectric constants by which the properties of these materials are described. The article then focuses on the basis of the piezoelectric response in synthetic polymers.Piezoelectricity or “pressure electricity” was coined from the Greek verb “piezen,” to press, by Pierre and Jacques Curie in the 1880s during an investigation of the symmetry in crystals. In this work it was found that certain crystals, lacking a center of symmetry, produced an electrical charge when mechanically deformed. The converse effect was also found to occur, whereby applying an electric field caused the crystal to change its shape. This phenomenon was attributed to a deformation of the net internal polarization in the crystal. When no external forces are present, the centers of positive and negative charges will coincide, and there is no net polarization. The application of a stress, be it mechanical (pressure) or electrical (applied field), causes a displacement of the centers of gravity of the positive and negative charges. In the absence of a center of symmetry, the charge displacement will be nonsymmetrical and thereby produce an induced dipole moment. This dipole moment, if produced by a mechanical stress, will cause the surfaces to develop an effective charge. If an external field displaces the charges, by electrostatic attraction or repulsion, it produces a mechanical strain which causes the material to deform. The mathematical relations describing this effect were developed in the few years following their discovery, making use of tensor notation to describe the directionality of the applied stress and the resultant strain.

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45

Kovaľ, Vladimír. "High aspect ratio lead zirconate titanate tube structures: I. Template assisted fabrication - vacuum infiltration method". Processing and Application of Ceramics 6, nr 1 (2012): 37–42. http://dx.doi.org/10.2298/pac1201037k.

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Polycrystalline Pb(Zr0.52Ti0.48 )O3 (PZT) microtubes are fabricated by a vacuum infiltration method. The method is based on repeated infiltration of precursor solution into macroporous silicon (Si) templates at a sub-atmospheric pressure. The pyrolyzed PZT tubes of a 2-?m outer diameter, extending to over 30 ?m in length were released from the template using a selective isotropic-pulsed XeF2 reactive ion etching of silicon. Free-standing microtubes, partially anchored at the bottom of the Si template, were then crystallized in pure oxygen atmosphere at 750 ?C for 2 min using a rapid thermal annealer. The perovskite phase of the final PZT tubes was confirmed by X-ray diffraction (XRD) analysis. The XRD spectrum also revealed a small amount of the pyrochlore phase in the structure and signs of possible fluoride contamination caused most likely by the XeF2 etching process. The surface morphology was examined using scanning electron microscopy. It was demonstrated that the whole surface of the pore walls was conformally coated during the repeated infiltration of templates, resulting in straight tubes with closed tips formed on the opposite ends as replicas of the pore bottoms. These high aspect ratio ferroelectric structures are suggested as building units for developing miniaturized electronic devices, such as memory storage (DRAM trenched) capacitors, piezoelectric scanners and actuators, and are of fundamental value for the theory of ferroelectricity in systems with low dimensionality.

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Gupta, Shashaank, Myoor K. Padmanabhan i Roop L. Mahajan. "Favorable dynamics of switching and non-switching polarizations in ⟨001⟩_pc oriented Sm:PMN-PT crystal". Applied Physics Letters 122, nr 12 (20.03.2023): 122903. http://dx.doi.org/10.1063/5.0140442.

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In this investigation, the dynamic behavior of the switching and the non-switching polarization loops has been studied for ⟨001⟩pc oriented PMN-PT and Sm:PMN-PT crystals. A five-pulse triangular wave sequence was employed to measure the switching and non-switching polarization loops separately as a function of amplitude and frequency of the poling field. Dynamic scaling of the switching loops was performed according to the power law [Formula: see text]. The lower negative value of [Formula: see text] for Sm:PMN-PT suggests a shorter response time of crystallographic domains for it as compared to that for PMN-PT. The value of exponent [Formula: see text] for PMN-PT was found to be higher in the low-field regime where 180° switching dominates the domain reorientation process. For Sm:PMN-PT, on the other hand, the value of [Formula: see text] was found to be higher at high fields, which implies a superior ferroelastic domain reorientation. A similar power law scaling was also performed on the non-switching loops, which suggests a faster dynamic response of intrinsic polarization in Sm:PMN-PT as compared to that for PMN-PT. However, the intrinsic polarization in Sm:PMN-PT was found to be less responsive to the increasing field as compared to that for PMN-PT. We believe that the findings of this investigation would add another dimension to the understanding of the mechanism responsible for the high piezoelectric activity in samarium doped PMN-0.28PT crystal and polycrystalline ceramics.

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Yu, Pei Jun. "Study on Artificial Polycrystalline Piezoelectric Material with the Calibration Mechanism of the Micro-Displacement Sensor Based on Piezoelectric Ceramic". Advanced Materials Research 703 (czerwiec 2013): 312–15. http://dx.doi.org/10.4028/www.scientific.net/amr.703.312.

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In this paper, a calibration mechanism of sensor based on artificial polycrystalline piezoelectric material and a kind of micro-voltage output system have been designed through understanding the characteristics and the parameters of the capacitive displacement sensor, so as to achieve the sensor calibration interval reaches the piezoelectric ceramic resolution of 5 nm. Through the measured values in the condition that 10mV/100mV is input to piezoelectric ceramic, it can be seen that the design meets the initial requirements. Such mechanism can be used for the calibration of a variety of high-precision sensors; however, it must be used in a stable environment.

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MAMATHA, B., i P. SARAH. "DIELECTRIC, FERROELECTRIC, PIEZOELECTRIC AND IMPEDANCE STUDY OF LEAD-FREE CERAMIC: SrBi4Ti3.975Zr0.025O15". Journal of Advanced Dielectrics 02, nr 04 (październik 2012): 1250023. http://dx.doi.org/10.1142/s2010135x12500233.

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Polycrystalline SrBi4Ti3.975Zr0.025O15 (SBTZ) was prepared using solid-state reaction technique. SBTZ was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD analysis indicated the formation of a single-phase orthorhombic structure. Particle size was found using SEM. The dielectric, ferroelectric, piezoelectric, modulus and impedance spectroscopy studies on SBTZ were investigated in the frequency range 1 Hz–1 MHz from room temperature (RT) to 600°C. Piezoelectric charge and electromechanical coupling coefficients were calculated from resonance and anti-resonance frequencies. Impedance and modulus plots were used as tools to analyze the sample behavior as a function of frequency. Cole–Cole plots showed a non-Debye relaxation. Conductivity measurements were performed on SBTZ.

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49

Jones, Jacob L., Benjamin J. Iverson i Keith J. Bowman. "Texture and Anisotropy of Polycrystalline Piezoelectrics". Journal of the American Ceramic Society 90, nr 8 (sierpień 2007): 2297–314. http://dx.doi.org/10.1111/j.1551-2916.2007.01820.x.

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Biglar, Mojtaba, Tomasz Trzepieciński, Feliks Stachowicz i Magdalena Gromada. "Application of the grain boundary formulation and image processing-based algorithm in micro-mechanical analysis of piezoelectric ceramic". Mathematics and Mechanics of Solids 25, nr 7 (14.10.2017): 1384–404. http://dx.doi.org/10.1177/1081286517735696.

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The main subject of this paper is the micro-mechanical analysis of a piezoelectric ceramic. In micro-mechanical analyses, it is very important to have knowledge about the real and natural micro-structure of materials. Therefore, the barium titanate powder was prepared using the solid-state technique, and pellets and beams were manufactured by uniaxial and isostatic pressing. The boundary element method (BEM) is used in order to be combined with three different grain boundary formulations for investigation of micro-mechanics and crack nucleation and evaluation in piezoelectric ceramic. In order to develop a numerical programming algorithm, suitable models of polycrystalline aggregate have to be discretised for the BEM analysis. Hence, original comprehensive algorithms are designed on the basis of image processing methods. Several assumptions are made to model the grain boundary in micro-scale. In the first step, before having any cracks, the traction equilibrium and displacement compatibility are governing equations. When the onset micro-crack starts to initiate, one mixed-mode potential based cohesive law is applied to model grain boundaries and investigate the intergranular crack nucleation and evolution. Upon interface failure, a frictional law is utilised in order to study separation, sliding or sticking between micro-crack surfaces. Several numerical experiments on barium titanate polycrystalline aggregate are presented to show the effectiveness of image processing-based discretisation algorithms and grain boundary formulation in micro-mechanical analysis.

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