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Sample records for zirconate titanate pzt

  1. Ferroelectric devices using lead zirconate titanate (PZT) nanoparticles.

    PubMed

    Paik, Young Hun; Kojori, Hossein Shokri; Kim, Sung Jin

    2016-02-19

    We successfully demonstrate the synthesis of lead zirconate titanate nanoparticles (PZT NPs) and a ferroelectric device using the synthesized PZT NPs. The crystalline structure and the size of the nanocrystals are studied using x-ray diffraction and transmission electron microscopy, respectively. We observe <100 nm of PZT NPs and this result matches dynamic light scattering measurements. A solution-based low-temperature process is used to fabricate PZT NP-based devices on an indium tin oxide substrate. The fabricated ferroelectric devices are characterized using various optical and electrical measurements and we verify ferroelectric properties including ferroelectric hysteresis and the ferroelectric photovoltaic effect. Our approach enables low-temperature solution-based processes that could be used for various applications. To the best of our knowledge, this low-temperature solution processed ferroelectric device using PZT NPs is the first successful demonstration of its kind. PMID:26788984

  2. Ferroelectric devices using lead zirconate titanate (PZT) nanoparticles

    NASA Astrophysics Data System (ADS)

    Paik, Young Hun; Shokri Kojori, Hossein; Kim, Sung Jin

    2016-02-01

    We successfully demonstrate the synthesis of lead zirconate titanate nanoparticles (PZT NPs) and a ferroelectric device using the synthesized PZT NPs. The crystalline structure and the size of the nanocrystals are studied using x-ray diffraction and transmission electron microscopy, respectively. We observe <100 nm of PZT NPs and this result matches dynamic light scattering measurements. A solution-based low-temperature process is used to fabricate PZT NP-based devices on an indium tin oxide substrate. The fabricated ferroelectric devices are characterized using various optical and electrical measurements and we verify ferroelectric properties including ferroelectric hysteresis and the ferroelectric photovoltaic effect. Our approach enables low-temperature solution-based processes that could be used for various applications. To the best of our knowledge, this low-temperature solution processed ferroelectric device using PZT NPs is the first successful demonstration of its kind.

  3. Electrostriction of composites of polyurethane (PU) with ferroelectric lead zirconate titanate (PZT) ceramic particles

    NASA Astrophysics Data System (ADS)

    Wong, Yuen-Wah; Liu, Chun-Xiao; Tai, Liang-Shiang; Shin, Franklin G.

    2001-07-01

    Electrostrictive composites of thermoplastic elastomer polyurethane (PU) and the ferroelectric lead zirconate titanate (PZT) of various volume fractions have been prepared by hot-roller miller. X-ray diffraction results and SEM micrographs showed that the ceramic crystallized in the ferroelectric phase and was dispersed uniformly in the elastomer. The elastic modulus and dielectric permittivity increased with PZT volume fractions. For composites of low PZT volume fraction, negative electrostrictive strain (contraction) was observed. As the PZT volume fraction increased to more than 6%, the composites exhibited a switching characteristic when the applied electric field was increased to a critical value. The critical electric fields decreased with increasing PZT volume fractions. This effect can be explained as the resultant of the electrostriction of PU and polarization reversal of the PZT at high field. This interesting property of the PU/PZT composite will lead to some switching actuations for high electric field applications.

  4. Fabrication and Characterization of Lead Zirconate Titanate (PZT) Thin Films by Sol-Gel Technique

    NASA Astrophysics Data System (ADS)

    Rahman, M. F.; Miglioli, L.

    2016-02-01

    In this work, thin lead zirconate titanate, Pb[Zr0.52Ti0.48]O3 (PZT) films have been developed from a novel sol-gel route. The sol-gel films were deposited by spin coating method. Isopropanol-based solution was used for its less toxic property. Gold (Au), platinum (Pt) and indium tin oxide (ITO) were used as substrates. Homogeneous polycrystalline films with (110) preferred orientation were obtained from all the films. The films behaved as ferroelectric material where dielectric constant at 0V for the films obtained from Au, Pt and ITO substrates were 484, 770 and 655, respectively. The coercive field values were around 10-15KV/cm which revealed that the films were soft ferroelectric.

  5. Mechanical and dielectric characterization of lead zirconate titanate(PZT)/polyurethane(PU) thin film composite for energy harvesting

    NASA Astrophysics Data System (ADS)

    Aboubakr, S.; Rguiti, M.; Hajjaji, A.; Eddiai, A.; Courtois, C.; d'Astorg, S.

    2014-04-01

    The Lead Zirconate titanate (PZT) ceramic is known by its piezoelectric feature, but also by its stiffness, the use of a composite based on a polyurethane (PU) matrix charged by a piezoelectric material, enable to generate a large deformation of the material, therefore harvesting more energy. This new material will provide a competitive alternative and low cost manufacturing technology of autonomous systems (smart clothes, car seat, boat sail, flag ...). A thin film of the PZT/PU composite was prepared using up to 80 vol. % of ceramic. Due to the dielectric nature of the PZT, inclusions of this one in a PU matrix raises the permittivity of the composite, on other hand this latter seems to decline at high frequencies.

  6. Lead zirconate titanate ceramics

    SciTech Connect

    Walker, B.E. Jr.

    1986-12-02

    This patent describes a lead zirconate titanate (PZT) piezoelectric ceramic composition which, based on total composition weight, consists essentially of a solid solution of lead zirconate and lead titanate in a PbZrO/sub 3/:PbTiO/sub 3/ ratio from about 0.505:0.495 to about 0.54:0.46; a halide salt selected from the group consisting of fluorides and chlorides of alkali metal and alkaline earth elements and mixtures thereof except for francium and radium in an amount from about 0.5 to 2 weight percent; and an oxide selected from the group consisting of magnesium, barium, scandium, aluminum, lanthanum, praesodynium, neodymium, samarium, and mixtures thereof in an amount from about 0.5 to about 6 weight percent, the relative amount of oxide being from about 1 to about 4 times that of the halide.

  7. Wafer-scale fabrication of self-actuated piezoelectric nanoelectromechanical resonators based on lead zirconate titanate (PZT)

    NASA Astrophysics Data System (ADS)

    Dezest, D.; Thomas, O.; Mathieu, F.; Mazenq, L.; Soyer, C.; Costecalde, J.; Remiens, D.; Deü, J. F.; Nicu, L.

    2015-03-01

    In this paper we report an unprecedented level of integration of self-actuated nanoelectromechanical system (NEMS) resonators based on a 150 nm thick lead zirconate titanate (PZT) thin film at the wafer-scale. A top-down approach combining ultraviolet (UV) lithography with other standard planar processing technologies allows us to achieve high-throughput manufacturing. Multilayer stack cantilevers with different geometries have been implemented with measured fundamental resonant frequencies in the megahertz range and Q-factor values ranging from ~130 in air up to ~900 in a vacuum at room temperature. A refined finite element model taking into account the exact configuration of the piezoelectric stack is proposed and demonstrates the importance of considering the dependence of the beam’s cross-section upon the axial coordinate. We extensively investigate both experimentally and theoretically the transduction efficiency of the implemented piezoelectric layer and report for the first time at this integration level a piezoelectric constant of {{d}31}=15  fm V-1. Finally, we discuss the current limitations to achieve piezoelectric detection.

  8. Reactive ion etching of lead zirconate titanate (PZT) thin film capacitors

    SciTech Connect

    Vijay, D.P.; Desu, S.B.; Pan, W. . Dept. of Materials Science and Engineering)

    1993-09-01

    One of the key processing concerns in the integration of PbZr[sub x]Ti[sub 1[minus]x]O[sub 3](PZT) thin film capacitors into the existing VLSI for ferroelectric or dynamic random access memory applications is the patterning of these films and the electrodes. In this work, the authors have identified a suitable etch gas (CCl[sub 2]F[sub 2]) for dry etching of PZT thin films on RuO[sub 2] electrodes. The etch rate and anisotropy have been studied as a function of etching conditions. The trends in the effect on the etch rate of the gas pressure, RF power and O[sub 2] additions to the etch gas have been determined and an etching mechanism has been proposed. It was found that ion bombardment effects are primarily responsible for the etching of both PZT and RuO[sub 2] thin films. Etch rates of the order of 20--30 nm/min were obtained for PZT thin films under low gas pressure and high RF power conditions. The etch residues and the relative etch rates of the components of the PZT solid solution were determined using XPS. The results show that the etching of PbO is the limiting factor in the etch process.

  9. Design, fabrication, test, and evaluation of RF MEMS series switches using lead zirconate titanate (PZT) thin film actuators

    NASA Astrophysics Data System (ADS)

    Polcawich, Ronald G.

    The aim of this thesis was to design and prototype a robust, low voltage RF MEMS switch for use in military phased arrays. The frequencies of interest for this work include very low frequencies down to DC operation with the upper limit extending to at least 40 GHz. This broad frequency requirement requires a robust high frequency design and simulation using microwave transmission lines. With the aid of researchers at the US Army Research Laboratory, co-planar waveguide (CPW) transmission lines were chosen and designed to provide a low loss, 50 ohm impedance transmission line for the switch. CPW designs allow for both series and shunt switch configuration with this work focusing on a series switch. Furthermore, a series switch an ohmic contact was chosen as opposed to capacitive contacts. Piezoelectric actuation is chosen for the switch to enable operating voltages less than 10 volts while still maintaining a restoring force to prevent stiction. To meet these demands, lead zirconate titanate (PZT) thin films have been chosen for the piezoelectric actuator. Mechanical modeling of cantilevers comprised of an elastic layer and a Pt-PZT-Pt actuator were used to demonstrate feasibility of closing large gaps between switch contacts. Placement of the actuator to minimize perturbations to the RF transmission line is critical for broadband performance. Using fabrication design rules, electro-mechanical modeling, and high frequency design, the actuators were designed to fit with the RF gap between the RF conductor and ground planes of the CPW transmission line. Optimal performance was obtained with the actuators mechanically isolated from a majority of the RF transmission except for a small section that provides the contact pad to enable switch closure. The resulting switch is the first demonstrated first surface micromachined RF MEMS switch operating from DC to 65 GHz. This switch has a median actuation voltage below 5 volts with operation as low as 2 volts. Isolation in the

  10. Improved pyroelectric performance for thin film lead zirconate titanate (PZT) capacitors with IrO2 electrodes

    NASA Astrophysics Data System (ADS)

    Hanrahan, B.; Sanchez, L.; Waits, C. M.; Polcawich, R. G.

    2016-01-01

    A four orders-of-magnitude reduction in high temperature leakage current was realized through the use of IrO2 top electrodes in thin film lead zirconate titanate capacitors which has been shown to directly impact the performance of future energy conversion applications. Pyroelectric energy conversion is enhanced near the material Curie temperature, but elevated leakage current in this temperature range hinders current applications. Conductivity experiments varying temperature, composition, and applied bias showed that oxygen vacancy hopping dominates the leakage current in the thin film capacitors above 200 °C. IrO2 top electrodes allow for a reduction in vacancy concentration by allowing for oxygen to be reintroduced during a post-processing annealing step for the thin film. The power lost to leakage current through the pyroelectric conversion cycle is explored. Improvements in remnant polarization and pyroelectric constant are also realized.

  11. Symmetries and multiferroic properties of novel room-temperature magnetoelectrics: Lead iron tantalate – lead zirconate titanate (PFT/PZT)

    DOE PAGESBeta

    Sanchez, Dilsom A.; Ortega, N.; Kumar, Ashok; Roque-Malherbe, R.; Polanco, R.; Scott, J. F.; Katiyar, Ram S.

    2011-12-01

    Mixing 60-70% lead zirconate titanate with 40-30% lead iron tantalate produces a single-phase, low-loss, room-temperature multiferroic with magnetoelectric coupling: (PbZr₀.₅₃Ti₀.₄₇O₃) (1-x)- (PbFe₀.₅Ta₀.₅O₃)x. The present study combines x-ray scattering, magnetic and polarization hysteresis in both phases, plus a second-order dielectric divergence (to epsilon = 6000 at 475 K for 0.4 PFT; to 4000 at 520 K for 0.3 PFT) for an unambiguous assignment as a C2v-C4v (Pmm2-P4mm) transition. The material exhibits square saturated magnetic hysteresis loops with 0.1 emu/g at 295 K and saturation polarization Pr = 25 μC/cm², which actually increases (to 40 μC/cm²) in the high-T tetragonal phase, representingmore » an exciting new room temperature oxide multiferroic to compete with BiFeO₃. Additional transitions at high temperatures (cubic at T>1300 K) and low temperatures (rhombohedral or monoclinic at T<250 K) are found. These are the lowest-loss room-temperature multiferroics known, which is a great advantage for magnetoelectric devices.« less

  12. Symmetries and multiferroic properties of novel room-temperature magnetoelectrics: Lead iron tantalate - lead zirconate titanate (PFT/PZT)

    NASA Astrophysics Data System (ADS)

    Sanchez, Dilsom A.; Ortega, N.; Kumar, Ashok; Roque-Malherbe, R.; Polanco, R.; Scott, J. F.; Katiyar, Ram S.

    2011-12-01

    Mixing 60-70% lead zirconate titanate with 40-30% lead iron tantalate produces a single-phase, low-loss, room-temperature multiferroic with magnetoelectric coupling: (PbZr0.53Ti0.47O3) (1-x)- (PbFe0.5Ta0.5O3)x. The present study combines x-ray scattering, magnetic and polarization hysteresis in both phases, plus a second-order dielectric divergence (to epsilon = 6000 at 475 K for 0.4 PFT; to 4000 at 520 K for 0.3 PFT) for an unambiguous assignment as a C2v-C4v (Pmm2-P4mm) transition. The material exhibits square saturated magnetic hysteresis loops with 0.1 emu/g at 295 K and saturation polarization Pr = 25 μC/cm2, which actually increases (to 40 μC/cm2) in the high-T tetragonal phase, representing an exciting new room temperature oxide multiferroic to compete with BiFeO3. Additional transitions at high temperatures (cubic at T>1300 K) and low temperatures (rhombohedral or monoclinic at T<250 K) are found. These are the lowest-loss room-temperature multiferroics known, which is a great advantage for magnetoelectric devices.

  13. Shear response of lead zirconate titanate piezoceramics

    NASA Astrophysics Data System (ADS)

    Mueller, V.; Zhang, Q. M.

    1998-04-01

    The piezoelectric shear strain S5 of several commercial lead zirconate titanate (PZT) piezoceramics was evaluated under the nonresonant condition in a sinusoidal ac-field E1(t) applied perpendicular to the poling direction. Results obtained on donor doped (soft PZT) and acceptor doped (hard PZT) ceramics are compared. At fields sufficiently below the limiting field Elim necessary to electrically depole the sample, we find a linear, nonhysteretic relationship between S5 and the polarization P1. In soft PZT ceramics, the effective piezoelectric shear coefficient d15=S5/E1 shows a pronounced ac-field dependence which was fitted according to d15(E1)=dlin[1+(dnlE1)α] with α≈1.2. The results indicate that irreversible motion of non-180° walls causes the nonlinearity of PZT and the contribution of 180° walls to the linear and nonlinear coefficients is negligible. The analysis of the relationship between linear and nonlinear coefficients obtained at different ceramic systems suggests that there exists another extrinsic contribution to the permittivity in PZT which may not be attributed to domain wall motion but may be responsible to the dielectric dispersion at microwave frequencies.

  14. Ferroelastic domains in lead-free barium zirconate titanate - barium calcium titanate piezoceramics

    NASA Astrophysics Data System (ADS)

    Ehmke, Matthias Claudius

    Piezoelectricity was first discovered by Pierre and Jaque Curie in the year 1880. Nowadays, piezoelectric materials are used in many application such as high voltage generation in gas igniters, actuation in micro-positioning devices, generation and detection of acoustic waves, emitters and receivers for sonar technology, ultrasonic cleaning, ultrasound medical therapy, and micropumps for ink-jet printers. The most commonly used piezoelectric material since the 1950's is the solid solution system lead zirconate titanate (PZT) that offers high piezoelectric performance under a large range of operating conditions. However, the toxicity of lead requires the replacement of PZT. The studied lead-free alternatives are commonly based on potassium sodium niobate (KNN) and bismuth sodium titanate (BNT), and more recently zirconium and calcium substituted barium titanate (BZT-BCT). The BZT-BCT system exhibits large piezoelectric coefficients that can exceed even those of most PZT compositions under certain conditions. Piezoelectricity was first discovered by Pierre and Jaque Curie in the year 1880. Nowadays, piezoelectric materials are used in many application such as high voltage generation in gas igniters, actuation in micro-positioning devices, generation and detection of acoustic waves, emitters and receivers for sonar technology, ultrasonic cleaning, ultrasound medical therapy, and micropumps for ink-jet printers. The most commonly used piezoelectric material since the 1950's is the solid solution system lead zirconate titanate (PZT) that offers high piezoelectric performance under a large range of operating conditions. However, the toxicity of lead requires the replacement of PZT. The studied lead-free alternatives are commonly based on potassium sodium niobate (KNN) and bismuth sodium titanate (BNT), and more recently zirconium and calcium substituted barium titanate (BZT-BCT). The BZT-BCT system exhibits large piezoelectric coefficients that can exceed even those of

  15. Piezoelectric lead zirconate titanate ceramic fiber/polymer composites

    SciTech Connect

    Waller, D.J.; Safari, P. )

    1992-06-01

    This papers on piezoelectric lead zirconate titanate (PZT) ceramic fiber/polymer composite were fabricated by a novel technique referred to as relic processing. Basically, this involved impregnating a woven carbon-fiber template material with PZT precursor by soaking the template in a PZT stock solution. Careful heat treatment pyrolized the carbon, resulting in a PZT ceramic relic that retained the fibrous template form. After sintering, the densified relic was backfilled with polymer to form a composite. Optimized relic processing consisted of soaking activated carbon-fiber fabric twice in an intermediate concentration (405-mg PZT/(1-g solution)) alkoxide PZT solution and sintering at 1285{degrees}C for 2 h. A series of piezoelectric composites encompassing a wide range of dielectric and piezoelectric properties was prepared by varying the PZT-fiber orientation and polymer-matrix material. In PZT/Eccogel polymer composites with PZT fibers orientated parallel to the electrodes, K = 75, d{sub 33} = 145 pC/N, d{sub h} = 45 {plus minus} 5 pC/N, and d{sub h}g{sub h} = 3150 {times} 10{sup {minus}15} m{sup 2}/N were measured. Furthermore, in composites with a number of PZT fibers arranged perpendicular to the electroded surfaces, K = 190, d{sub 33} = 250 pC/N, d{sub h} = 65 {plus minus} 2 pC/N, and d{sub h}g{sub h} = 2600 {times} 10{sup {minus}15} m{sub 2}/N.

  16. Measurement of incident position of hypervelocity particles on piezoelectric lead zirconate titanate detector

    SciTech Connect

    Takechi, Seiji; Onishi, Toshiyuki; Minami, Shigeyuki; Miyachi, Takashi; Fujii, Masayuki; Hasebe, Nobuyuki; Nogami, Ken-ichi; Ohashi, Hideo; Sasaki, Sho; Shibata, Hiromi; Iwai, Takeo; Gruen, Eberhard; Srama, Ralf; Okada, Nagaya

    2008-04-15

    A cosmic dust detector for use onboard a satellite is currently being developed by using piezoelectric lead zirconate titanate (PZT). The characteristics of the PZT detector have been studied by bombarding it with hypervelocity iron (Fe) particles supplied by a Van de Graaff accelerator. One central electrode and four peripheral electrodes were placed on the front surface of the PZT detector to measure the impact positions of the incident Fe particles. It was demonstrated that the point of impact on the PZT detector could be identified by using information on the time at which the first peak of the output signal obtained from each electrode appeared.

  17. Fabrication and Characterization of a Lead Zirconate Titanate Micro Energy Harvester Based on Eutectic Bonding

    NASA Astrophysics Data System (ADS)

    Li, Yi-Gui; Sun, Jian; Yang, Chun-Sheng; Liu, Jing-Quan; Sugiyama, Susumu; Tanaka, Katsuhiko

    2011-06-01

    A lead zirconate titanate(PZT)-Si energy harvester cantilever with PZT bulk ceramics is fabricated by eutectic bonding, polishing and dicing processes. The feasibility of this process is studied using a successful operation of the cantilever in both actuation and harvesting modes. The first prototype made from a PZT-Au-Si cantiliever is tested. The testing results show the voltage output of 632 mV at the frequency of 815 Hz when the excitation acceleration is 0.5 g. The PZT and silicon layers are bonded together to form a sandwiched structure using a gold layer as an intermediate layer.

  18. Interaction of piezoelectric lead zirconate titanate with 400 MeV/n xenon beam

    NASA Astrophysics Data System (ADS)

    Takechi, Seiji; Morinaga, Shin-ya; Kurozumi, Atsuma; Miyachi, Takashi; Fujii, Masayuki; Hasebe, Nobuyuki; Shibata, Hiromi; Murakami, Takeshi; Uchihori, Yukio; Okada, Nagaya

    2010-05-01

    The characteristics of radiation detector fabricated by stacking some piezoelectric lead zirconate titanate (PZT) elements were studied by irradiating it with a 400 MeV/n xenon (Xe) beam. Comparing between observed results from the detector and calculation results using Bethe-Bloch formula, it was found that the amplitude of the output voltage observed was dependent on the amount of ionization energy loss of Xe ion with PZT.

  19. Effects of rapid thermal annealing on nucleation, growth, and properties of lead zirconate titanate films.

    PubMed

    Lu, Jian; Zhang, Yi; Ikehara, Tsuyoshi; Mihara, Takashi; Maeda, Ryutaro

    2007-12-01

    The nucleation and growth behavior of solgel-derived lead zirconate titanate (PZT) films was investigated at different rapid thermal annealing (RTA) processes. The effects of RTA on PZT film surface morphology, crystal orientation, residual stress, and properties were also studied and are discussed. PZT nucleation and growth behavior were found to be more sensitive to heating rate than to hold time during RTA. Higher heating rates were preferred for uniform PZT nucleation and grain growth, which resulted in dense microstructures, smooth surfaces, and better film ferroelectric properties. Lower heating rates led to strong PZT (100) orientation, better film piezoelectric properties, and low residual stress, but at the risk of film cracks caused by arbitrarily distributed large crystallites with diameters of approximately 300 nm among crystallites with diameters of approximately 30 nm. Furthermore, the residual stress of the PZT film was found to be effectively reduced by extending the hold time. PMID:18276553

  20. Relationship between orientation factor of lead zirconate titanate nanowires and dielectric permittivity of nanocomposites

    SciTech Connect

    Tang, Haixiong E-mail: hsodano@ufl.edu; Malakooti, Mohammad H.; Sodano, Henry A. E-mail: hsodano@ufl.edu

    2013-11-25

    The relationship between the orientation of lead zirconate titanate (PZT) nanowires dispersed in nanocomposites and the resulting dielectric constants are quantified. The orientation of the PZT nanowires embedded in a polymer matrix is controlled by varying the draw ratio and subsequently quantified using Herman's Orientation Factor. Consequently, it is demonstrated that the dielectric constants of nanocomposites are improved by increasing the orientation factor of the PZT nanowires. This technique is proposed to improve the dielectric constant of the nanocomposites without the need for additional filler volume fraction since the nanocomposites are utilized in a wide range of high dielectric permittivity electronic components.

  1. Properties of ultra-thin lead zirconate titanate thin films prepared by ozone jet reactive evaporation

    NASA Astrophysics Data System (ADS)

    Torii, Kazuyoshi; Kawakami, Hirosi; Miki, Hiroshi; Kushida, Keiko; Fujisaki, Yoshihisa

    1997-03-01

    Lead zirconate titanate (PZT) thin films were prepared by reactive coevaporation with high-concentration ozone. PZT thin films that demonstrate the highest charge storage density (280 fC/μm2 at 1.5 V for 75-nm-thick film) yet reported have been fabricated. No fatigue was observed after 1011 polarization switching cycles even though a Pt electrode is used. A low leakage current of <10-7 A/cm2 at 1.5 V was attained. These PZT films are promising candidates of an alternative capacitor dielectric for dynamic random access memory (DRAM) and ferroelectric nonvolatile memories.

  2. Dielectric and pyroelectric properties of lead zirconate titanate/polyurethane composites

    SciTech Connect

    Lam, K.S.; Wong, Y.W.; Tai, L.S.; Poon, Y.M.; Shin, F.G.

    2004-10-01

    0-3 composite ranging between 0 and 3, of ferroelectric ceramic lead zirconate titanate (PZT) and thermoplastic elastomer polyurethane (PU) were fabricated. The pyroelectric and dielectric properties of the hot-pressed thin film samples of various PZT volume fractions were measured. The experimental dielectric permittivities and losses agreed reasonably well with the Bruggeman model. The room temperature pyroelectric coefficients of the composites were found to increase linearly with PZT volume fraction and substantially larger than expected. For example, for a composite with 30% PZT, its pyroelectric coefficient is about 90 {mu}C/m{sup 2}K at room temperature, which is more than tenfold of a PZT/PVDF composite of the same ceramic volume fraction. We propose a model in which the electrical conductivity of the composite system is taken into consideration to explain the linear relationship and the extraordinarily large pyroelectric coefficients obtained.

  3. Acoustic signals generated in piezoelectric lead zirconate titanate elements by direct bombardment with xenon ions

    NASA Astrophysics Data System (ADS)

    Miyachi, T.; Nakamura, Y.; Kuraza, G.; Fujii, M.; Nagashima, A.; Hasebe, N.; Kobayashi, M. N.; Kobayashi, S.; Miyajima, M.; Mori, K.; Okudaira, O.; Yamashita, N.; Shibata, H.; Murakami, T.; Uchihori, Y.; Okada, N.

    2006-12-01

    Acoustic signals were observed with a lead-zirconate-titanate (PZT) element that was directly irradiated with a 368 MeV/n xenon beam. Using an array comprising PZT elements, the energy loss in the PZT was studied. These elements are sensitive to an energy deposit of 100 nJ. A series of values of output voltage vs. integrated thickness of PZT was represented along a line similar to the ionization loss calculated by the Bethe-Bloch formula. The induced voltage was attributed to several processes—ionization, thermal, elastic, and piezoelectric processes. This study describes the possible applications of the PZT element as an active medium for calorimeters and a monitor for hypervelocity impact of space dust.

  4. Dielectric and pyroelectric properties of lead zirconate titanate/polyurethane composites

    NASA Astrophysics Data System (ADS)

    Lam, K. S.; Wong, Y. W.; Tai, L. S.; Poon, Y. M.; Shin, F. G.

    2004-10-01

    0-3 composite ranging between 0 and 3, of ferroelectric ceramic lead zirconate titanate (PZT) and thermoplastic elastomer polyurethane (PU) were fabricated. The pyroelectric and dielectric properties of the hot-pressed thin film samples of various PZT volume fractions were measured. The experimental dielectric permittivities and losses agreed reasonably well with the Bruggeman model. The room temperature pyroelectric coefficients of the composites were found to increase linearly with PZT volume fraction and substantially larger than expected. For example, for a composite with 30% PZT, its pyroelectric coefficient is about 90μC/m2K at room temperature, which is more than tenfold of a PZT/PVDF composite of the same ceramic volume fraction. We propose a model in which the electrical conductivity of the composite system is taken into consideration to explain the linear relationship and the extraordinarily large pyroelectric coefficients obtained.

  5. Helmholtz Resonator for Lead Zirconate Titanate Acoustic Energy Harvester

    NASA Astrophysics Data System (ADS)

    Matsuda, Tomohiro; Tomii, Kazuki; Hagiwara, Saori; Miyake, Shuntaro; Hasegawa, Yuichi; Sato, Takamitsu; Kaneko, Yuta; Nishioka, Yasushiro

    2013-12-01

    Acoustic energy harvesters that function in environments where sound pressure is extremely high (~150 dB), such as in engine rooms of aircrafts, are expected to be capable of powering wireless health monitoring systems. This paper presents the power generation performances of a lead-zirconate-titanate (PZT) acoustic energy harvester with a vibrating PZT diaphragm. The diaphragm had a diameter of 2 mm, consisting of Al(0.1 μm)/PZT(1 μm)/Pt(0.1 μm)/Ti(0.1 μm)/SiO2(1.5 μm). The harvester generated a power of 1.7×10-13 W under a sound pressure level of 110 dB at the first resonance frequency of 6.28 kHz. It was found that the generated power was increased to 6.8×10-13 W using a sound-collecting Helmholtz resonator cone with the height of 60 mm. The cone provided a Helmholtz resonance at 5.8 kHz, and the generated power increased from 3.4×10-14 W to 1.4×10-13 W at this frequency. The cone was also effective in increasing the bandwidth of the energy harvester.

  6. Simulation and calculation of the piezoelectric modulus of a lead zirconate-titanate thin film in a test microstructure

    SciTech Connect

    Amelichev, V. V.; Saikin, D. A.; Roshchin, V. M.; Silibin, M. V.

    2010-12-15

    Results of simulation of stresses in the test structure of a silicon beam and analytical calculation of piezoelectric modulus d{sub 31} of a lead zirconate-titanate (PZT) thin film arranged in the region of an elastic element are presented. The characteristics of the sensitive element of acceleration are calculated based on a PZT thin film with an inertial mass made of silicon.

  7. Pb nanowire formation on Al/lead zirconate titanate surfaces in high-pressure hydrogen

    SciTech Connect

    Alvine, Kyle J.; Shutthanandan, V.; Arey, Bruce W.; Wang, Chong M.; Bennett, Wendy D.; Pitman, Stan G.

    2012-07-12

    Thin films of Al on lead zirconate titanate (PZT) annealed in high-pressure hydrogen at 100C exhibit surface Pb nanowire growth. Wire diameter is approximately 80 nm and length can exceed 100 microns. Based on microstructural analysis using electron microscopy and ion scattering, a vapor-solid scheme with hydrogen as a carrier gas was proposed as a growth mechanism. We expect that these observations may lead to controlled Pb nanowires growth through pattering of the Al film.

  8. Enhanced piezoelectric property of porous lead zirconate titanate ceramics with one dimensional ordered pore structure

    SciTech Connect

    Guo Rui; Wang Changan; Yang Ankun; Fu Juntao

    2010-12-15

    Lead zirconate titanate (PZT) ceramics with one dimensional ordered pore structure (1-3 type porous PZT ceramics) were fabricated in this study. The special structure not only enhanced the piezoelectric and dielectric properties effectively but also further decreased the acoustic impedance. All samples exhibited excellent piezoelectric properties despite high porosities. The d{sub 33} value was 608 pC /N (remained 88% that of dense PZT) when the porosity was up to 68.7%. The d{sub 33} value was 690 pC /N (same as dense PZT) when the porosity was 41.7%. The lowest acoustic impedance (Z) reached 1.3 MRayls. These results are promising for improving performance in hydrophones applications.

  9. Detection of high-energy heavy ions using piezoelectric lead zirconate titanate

    SciTech Connect

    Takechi, Seiji; Morinaga, Shin-ya; Kurozumi, Atsuma; Miyachi, Takashi; Fujii, Masayuki; Hasebe, Nobuyuki; Shibata, Hiromi; Murakami, Takeshi; Uchihori, Yukio; Okada, Nagaya

    2009-04-15

    The characteristics of a radiation detector fabricated with stacks of piezoelectric lead zirconate titanate (PZT) elements were studied by irradiating it with a 400 MeV/n xenon (Xe) beam for various beam pulse durations. This detector is referred to as the multilayered detector (MD). To understand the production mechanism behind the output voltage obtained from the MD, measurement of the spatial distribution of the output signals generated in the MD was attempted. It was found that the amplitude observed was dependent on the number of Xe ions per unit time and the amount of ionization loss energy of Xe ions in PZT.

  10. Nonlinearity and Scaling Behavior in Lead Zirconate Titanate Piezoceramic

    NASA Astrophysics Data System (ADS)

    Mueller, V.

    1998-03-01

    The results of a comprehensive study of the nonlinear dielectric and electromechanical response of lead zirconate titanate (PZT) piezoceramics are presented. The piezoelectric strain of a series of donor doped (soft PZT) and acceptor doped (hard PZT) polycrystalline systems was measured under quasistatic (nonresonant) conditions. The measuring field was applied both parallel and perpendicular to the poling direction of the ceramic in order to investigate the influence of different symmetry conditions. Dielectric properties were studied in addition to the electromechanical measurements which enables us to compare piezoelectric and dielectric nonlinearities. Due to the different level and type of dopants, the piezoceramics examined differ significantly with regard to its Curie temperature (190^o CPZT, two different effective thresholds for the onset of nonlinearity of dielectric and piezoelectric coefficients are found at electric ac-fields E_c1≈ 100V/cm and E_c2 ≈ 1V/cm, respectively. Both are characterized by non-analytic scaling behavior \\chi (E_ac) = \\chi_lin+ A[(E-E_c)/E_c]^φ above the respective threshold. The values of the effective exponent φ are apparently independent of the particular ceramic system which indicates a universal behavior of soft PZT. Hard PZT exhibits a less pronounced nonlinearity and a threshold E_c2≈ 1000V/cm at higher field level than soft PZT. The low field behavior of hard PZT seems to be related to a gradual depinning of ferroelectric domain walls with individual depinning threshold whereas in large fields E>E_c2 the

  11. Pyroelectric response of lead zirconate titanate thin films on silicon: Effect of thermal stresses

    SciTech Connect

    Kesim, M. T.; Zhang, J.; Alpay, S. P.; Trolier-McKinstry, S.; Mantese, J. V.; Whatmore, R. W.

    2013-11-28

    Ferroelectric lead zirconate titanate [Pb(Zr{sub x}Ti{sub 1-x}O){sub 3}, (PZT x:1-x)] has received considerable interest for applications related to uncooled infrared devices due to its large pyroelectric figures of merit near room temperature, and the fact that such devices are inherently ac coupled, allowing for simplified image post processing. For ferroelectric films made by industry-standard deposition techniques, stresses develop in the PZT layer upon cooling from the processing/growth temperature due to thermal mismatch between the film and the substrate. In this study, we use a non-linear thermodynamic model to investigate the pyroelectric properties of polycrystalline PZT thin films for five different compositions (PZT 40:60, PZT 30:70, PZT 20:80, PZT 10:90, PZT 0:100) on silicon as a function of processing temperature (25–800 °C). It is shown that the in-plane thermal stresses in PZT thin films alter the out-of-plane polarization and the ferroelectric phase transformation temperature, with profound effect on the pyroelectric properties. PZT 30:70 is found to have the largest pyroelectric coefficient (0.042 μC cm{sup −2} °C{sup −1}, comparable to bulk values) at a growth temperature of 550 °C; typical to what is currently used for many deposition processes. Our results indicate that it is possible to optimize the pyroelectric response of PZT thin films by adjusting the Ti composition and the processing temperature, thereby, enabling the tailoring of material properties for optimization relative to a specific deposition process.

  12. Gas Flow Sputtered Thick Layers of Columnar Lead Zirconate Titanate on Silicon Wafers for High Frequency Ultrasound Transducers

    NASA Astrophysics Data System (ADS)

    Tiefensee, F.; Kaden, D.; Jakob, A.; Quenzer, H. J.; Jung, Th.

    The piezoelectric ceramic PZT, lead zirconate titanate, is the most spread material to generate ultrasound in medical and technical applications. Thereby frequencies between 30 MHz and 100 MHz require ceramic thicknesses between 50 μm and 20 μm. The presented gas flow sputtering process permits to deposit PZT of this thickness with a sputtering rate of 100 nm/min at temperatures between 520 °C and 550 °C. The PZT shows a typical columnar structure with a piezoelectric coefficient d33f of about 500 pm/V. An example for the fabrication ultrasound arrays with this sputtering process and lithographic structuring is given.

  13. Hot-Pressed Ferrite-Lead Zirconate Titanate Magnetoelectric Composites

    NASA Astrophysics Data System (ADS)

    Devreugd, C. P.; Srinivasan, G.; Micheli, A. L.; Mantese, J. V.

    2004-03-01

    The electromagnetic coupling in magnetostrictive/piezoelectric is mediated by mechanical stress: magnetostriction induced mechanical deformation and piezoelectric effect induced electric fields. Composites studied so far include ferrite-lead zirconate titanate (PZT) and manganite-PZT [1-3]. Bulk or layered composites are usually synthesized by conventional sintering of mixture of powders or laminated thick films. This study is concerned with the fabrication of novel ferromagnetic-ferroelectric bulk and thin film layered composites by hot pressing together with studies on the nature of magnetoelectric interactions. The objective is to obtain defect free samples with good interface coupling. Systems studied includes Ni-Zn, Co-Zn and Co-Ni ferrites that are predicted to show high piezomagnetic and magnetomechanical couplings and PZT. Samples were prepared using aluminum oxide or high temperature alloy dies. Sintering was done at 1300 K at a pressure of 5000-7000 psi. Measurements of transverse and longitudinal ME coefficients are performed at low frequencies (10 Hz-1kHz), and at electromechanical resonance (100-300 kHz). Important results of our studies are follows. (1) Hot-pressed samples show an order of magnitude improvement in ME voltage coefficient compared to samples processed by conventional sintering. The enhancement is attributed to an increase in density, sample resistivity, and interface coupling. (2) The longitudinal coupling is stronger than the transverse effect. (3) There is a significant increase in ME interactions at electromechanical resonance. (4) Samples with Ni-Zn ferrites show the highest ME coefficients. The results are analysed using our model for a bulk composite. - supported by a grant from the National Science Foundation (DMR-0322254) 1. G. Srinivasan, E. T. Rasmussen, J. Gallegos, Yu. I. Bokhan, and V. M. Laletin, Phys. Rev. B, 64, 214408 (2001). 2. G. Srinivasan, E. T. Rasmussen, B. J. Levin, and R. Hayes, Phys. Rev. B 65, 134402 (2002). 3

  14. Dual Piezoelectric Actuation Bridge of In-Plane Polarized Lead Zirconate Titanate Film

    NASA Astrophysics Data System (ADS)

    Hwang, Hyun-Suk; Song, Joon-Tae

    2008-08-01

    A dual piezoelectric actuation bridge of in-plane polarized lead zirconate titanate (PZT) film is demonstrated. The in-plane polarized PZT film makes the development of a bending mechanism in the d33 mode, which exhibits a strain performance twice that of the d31 mode. Further, this design can provide deflection exceeding the structure thickness and individual driving mechanism for improving reliability of the devices. In order to simplify the fabrication process, a photoresist and Au are selected for the sacrificial and structural materials, respectively. The PZT thin film, which is deposited on the Au structural layer by the RF magnetron sputtering method, is poled and driven with interdigitated electrodes (IDEs) in order to exploit d33 mode actuation. The fabricated actuator exhibits good performance with a fast response time of <500 ms and low driving voltage of 5 V. This design can also be applied for a linearly tunable capacitor, depending on the magnitude of biasing voltage.

  15. Phase separation in lead zirconate titanate and bismuth titanate during electrical shorting and fatigue

    NASA Astrophysics Data System (ADS)

    Lou, Xiaojie; Hu, Xiaobing; Zhang, Ming; Morrison, F. D.; Redfern, S. A. T.; Scott, J. F.

    2006-02-01

    Micro-Raman and electron microprobe techniques are used to show that lead zirconate titanate and samarium-doped bismuth titanate undergo local phase transformations and separation during electrical shorting and in the dendritic precursors to microshorts caused by bipolar fatigue. These precursors for shorts, consisting of dark filaments, were studied just before they completely shorted the sample. The aim of the study was to compare electrical breakdown and breakdown precursors in ABO3 perovskite oxides and related Aurivillius phase layer structures with Bi (A site) substitution and with B-site substitution (e.g., Ti for Zr in PZT). The observation of phase separation and decomposition is related to congruent and incongruent meltings in these materials. Dendritelike shorts and short precursors of a few microns in diameter, produced by extreme bipolar voltage cycling fatigue, are mapped spectroscopically in 1 μm2 areas and exhibit almost pure regions of α-PbO, β-PbO, and rutile TiO2. The α-β PbO phase boundary runs from 500 °C at 1 atm to room temperature at 0.4 GPa, easily accessible temperatures and pressures in the dynamical process. Similarly, under large dc voltages the Sm-doped bismuth titanate transforms from a layered-perovskite structure to a pyrochlore structure during filamentary electrical breakdown, with the loss of Bi. The interfacial phase separation has been attributed to the combination of defect aggregation and thermal decomposition effects.

  16. Effects of Electric Field and Biaxial Flexure on the Failure of Poled Lead Zirconate Titanate

    SciTech Connect

    Wang, Hong; Wereszczak, Andrew A

    2008-01-01

    Reliable design of lead zirconate titanate (PZT) piezo stack actuators demands that a number of issues, including electromechanical coupling and ceramic strength-size scaling, be scrutinized. This study addresses those through the use of ball-on-ring (BoR) biaxial flexure strength tests of a PZT piezoelectric material that is concurrently subjected to an electric field. The Weibull strength distributions and fracture surfaces were examined. The mechanical failures were further analyzed in terms of internal stress, energy release rate, and domain-switching toughening. Both the sign and the magnitude of an electric field had a significant effect on the strength of poled PZT within the tested range. A surface flaw type with a depth of ~18 m was identified to be the strength limiter and responsible for the failure of the tested PZT under both mechanical and electromechanical loadings. With ~0.74 in the absence of electric field, the fracture toughness of the poled PZT was affected by an applied electric field just as the strength was affected. These results and observations have the potential to serve probabilistic reliability analysis and design optimization of multilayer PZT piezo actuators.

  17. Temperature Dependent Electrical Properties of PZT Wafer

    NASA Astrophysics Data System (ADS)

    Basu, T.; Sen, S.; Seal, A.; Sen, A.

    2016-04-01

    The electrical and electromechanical properties of lead zirconate titanate (PZT) wafers were investigated and compared with PZT bulk. PZT wafers were prepared by tape casting technique. The transition temperature of both the PZT forms remained the same. The transition from an asymmetric to a symmetric shape was observed for PZT wafers at higher temperature. The piezoelectric coefficient (d 33) values obtained were 560 pc/N and 234 pc/N, and the electromechanical coupling coefficient (k p) values were 0.68 and 0.49 for bulk and wafer, respectively. The reduction in polarization after fatigue was only ~3% in case of PZT bulk and ~7% for PZT wafer.

  18. Fatigue of extracted lead zirconate titanate multilayer actuators under unipolar high field electric cycling

    SciTech Connect

    Wang, Hong Lee, Sung-Min; Wang, James L.; Lin, Hua-Tay

    2014-12-21

    Testing of large prototype lead zirconate titanate (PZT) stacks presents substantial technical challenges to electronic testing systems, so an alternative approach that uses subunits extracted from prototypes has been pursued. Extracted 10-layer and 20-layer plate specimens were subjected to an electric cycle test under an electric field of 3.0/0.0 kV/mm, 100 Hz to 10{sup 8} cycles. The effects of measurement field level and stack size (number of PZT layers) on the fatigue responses of piezoelectric and dielectric coefficients were observed. On-line monitoring permitted examination of the fatigue response of the PZT stacks. The fatigue rate (based on on-line monitoring) and the fatigue index (based on the conductance spectrum from impedance measurement or small signal measurement) were developed to quantify the fatigue status of the PZT stacks. The controlling fatigue mechanism was analyzed against the fatigue observations. The data presented can serve as input to design optimization of PZT stacks and to operation optimization in critical applications, such as piezoelectric fuel injectors in heavy-duty diesel engines.

  19. Fatigue of extracted lead zirconate titanate multilayer actuators under unipolar high field electric cycling

    DOE PAGESBeta

    Wang, Hong; Lee, Sung Min; Wang, James L.; Lin, Hua-Tay

    2014-12-19

    Testing of large prototype lead zirconate titanate (PZT) stacks presents substantial technical challenges to electronic testing systems, so an alternative approach that uses subunits extracted from prototypes has been pursued. Extracted 10-layer and 20-layer plate specimens were subjected to an electric cycle test under an electric field of 3.0/0.0 kV/mm, 100 Hz to 10^8 cycles. The effects of measurement field level and stack size (number of PZT layers) on the fatigue responses of piezoelectric and dielectric coefficients were observed. On-line monitoring permitted examination of the fatigue response of the PZT stacks. The fatigue rate (based on on-line monitoring) and themore » fatigue index (based on the conductance spectrum from impedance measurement or small signal measurement) were developed to quantify the fatigue status of the PZT stacks. The controlling fatigue mechanism was analyzed against the fatigue observations. The data presented can serve as input to design optimization of PZT stacks and to operation optimization in critical applications such as piezoelectric fuel injectors in heavy-duty diesel engines.« less

  20. Fatigue of extracted lead zirconate titanate multilayer actuators under unipolar high field electric cycling

    SciTech Connect

    Wang, Hong; Lee, Sung Min; Wang, James L.; Lin, Hua-Tay

    2014-12-19

    Testing of large prototype lead zirconate titanate (PZT) stacks presents substantial technical challenges to electronic testing systems, so an alternative approach that uses subunits extracted from prototypes has been pursued. Extracted 10-layer and 20-layer plate specimens were subjected to an electric cycle test under an electric field of 3.0/0.0 kV/mm, 100 Hz to 10^8 cycles. The effects of measurement field level and stack size (number of PZT layers) on the fatigue responses of piezoelectric and dielectric coefficients were observed. On-line monitoring permitted examination of the fatigue response of the PZT stacks. The fatigue rate (based on on-line monitoring) and the fatigue index (based on the conductance spectrum from impedance measurement or small signal measurement) were developed to quantify the fatigue status of the PZT stacks. The controlling fatigue mechanism was analyzed against the fatigue observations. The data presented can serve as input to design optimization of PZT stacks and to operation optimization in critical applications such as piezoelectric fuel injectors in heavy-duty diesel engines.

  1. Hydrogen diffusion in lead zirconate titanate and barium titanate

    SciTech Connect

    Alvine, K. J.; Vijayakumar, M.; Bowden, M. E.; Schemer-Kohrn, A. L.; Pitman, S. G.

    2012-08-28

    Hydrogen is a potential clean-burning, next-generation fuel for vehicle and stationary power. Unfortunately, hydrogen is also well known to have serious materials compatibility issues in metals, polymers, and ceramics. Piezoelectric actuator materials proposed for low-cost, high efficiency high-pressure hydrogen internal combustion engines (HICE) are known to degrade rapidly in hydrogen. This limits their potential use and poses challenges for HICE. Hydrogen-induced degradation of piezoelectrics is also an issue for low-pressure hydrogen passivation in ferroelectric random access memory. Currently, there is a lack of data in the literature on hydrogen species diffusion in piezoelectrics in the temperature range appropriate for the HICE as charged via a gaseous route. We present 1HNMR quantification of the local hydrogen species diffusion within lead zirconate titanate and barium titanate on samples charged by exposure to high-pressure gaseous hydrogen ~32 MPa. We discuss results in the context of theoretically predicted interstitial hydrogen lattice sites and aqueous charging experiments from existing literature.

  2. Pressure-temperature phase diagram for a tin modified lead zirconate titanate ceramic.

    SciTech Connect

    Grubbs, Robert K.; DiAntonio, Christopher Brian; Yang, Pin; Roesler, Alexander William; Montgomery, Stephen Tedford; Moore, Roger Howard

    2010-06-01

    Structural phase transformations between ferroelectric (FE), antiferroelectric (AFE), and paraelectric (FE) phases are frequently observed in the zirconia-rich phase region on the lead zirconate-titanate (PZT) phase diagram. Since the free energy difference among these phases is small, phase transformation can be easily induced by temperature, pressure and electric field. These induced transformation characteristics have been used for many practical applications. This study focuses on a hydrostatic pressure induced FE-to-AFE phase transformation in a tin modified PZT ceramic (PSZT). The relative phase stability between FE and AFE phases is determined by the dielectric permittivity measurement as a function of temperature from -60 C to 125 C. A pressure-temperature phase diagram for the PSZT system will be presented.

  3. Longitudinal electroptic effects and photosensitivities of lead zirconate titanate thin films

    SciTech Connect

    Land, C.E. )

    1989-11-01

    The feasibility of storing and reading high-density optical information in lead zirconate titanate (PZT) and in lead lanthanum zirconate titanate (PLZT) thin films depends on both the longitudinal electrooptic coefficients and the photosensitivities of the films. This paper describes the methods used to measure the longitudinal electrooptic effects and the photosensitivities of the films. The results of these measurements were used to evaluate a longitudinal quadratic electrooptic R coefficient, a longitudinal linear electrooptic r{sub c} coefficient, and the wavelength dependence of the photosensitivity of a composition of PZT polycrystalline thin film. The longitudinal electrooptic R and r{sub c} coefficients are about an order of magnitude less than the transverse R and r{sub c} coefficients of bulk ceramics of similar compositions. This is attributed to clamping of the film by the rigid substrate. The large birefringence of the films after poling (>10{sup {minus} 2}) suggests that the optic axes of the films are preferentially oriented normal to the film surface. The techniques used in this paper for evaluating the photosensitivities of thin films are based on measuring the photocurrent generated rather than the reduction in coercive voltage (as in bulk ceramics) when the film is exposed to light.

  4. Optimum reaction conditions for lead zirconate titanate thick film deposition by ultrasound-assisted hydrothermal method

    NASA Astrophysics Data System (ADS)

    Saigusa, Katsuhiro; Morita, Takeshi

    2016-07-01

    A hydrothermal method can be used to deposit lead zirconate titanate (PZT) films and has several advantages, such as a relatively low reaction temperature and high crystal quality. We developed an ultrasound-assisted hydrothermal method to promote the hydrothermal reactions, which is effective for thick-PZT-film deposition. The first ultrasound-assisted hydrothermal method we developed can synthesize a 7.5 µm PZT film on a titanium substrate. However, for a much thicker film, repeated depositions were required, and the optimum precursor solution for the first deposition was not suitable for repeated depositions. In this study, we attempted to find the optimum precursor solution for depositing a film of sufficient thickness by repeated depositions. As a result, we were able to synthesize a 23.6 µm PZT film on second deposition by changing the ratio of zirconium to titanium ions in the precursor solutions. In addition, a transverse effect transducer was fabricated under optimum conditions and its vibration properties were evaluated.

  5. Biaxial Flexural Strength of Poled Lead Zirconate Titanate under High Electric Field with Extended Field Range

    SciTech Connect

    Zhang, Kewei; Zeng, Fan W; Wang, Hong; Lin, Hua-Tay

    2013-01-01

    In the present work, as-received poled lead zirconate titanate, or PZT 5A, was examined using ball-on-ring (BoR) mechanical testing coupled with an electric field. Electric fields in the range of 4Ec (Ec, coercive field) with controlled loading paths were applied, and mechanical tests at a substantial number of characteristic electric field levels were conducted. Commercial electronic liquid FC-40 was used to prevent the setup from dielectric breakdown under a high electric field. Weibull strength distribution was used to interpret the mechanical strength data. The data showed that the strength levels of the PZT-5A tested under OC (open circuit) in air and in FC-40 were almost the same. It was further revealed that , for the studied cases, the effect of loading history on the biaxial flexural strength of the PZT was significant in -Ec, but not in OC or zero field as well as 4Ec . An asymmetry V curve was observed for the characteristic strength-electric field graph, and the bottom of V curve was located near the negative coercive field. Microscopy analysis showed that surface-located volume-distributed flaws were the strength limiter and responsible for the failure of the tested PZT under electromechanical loadings.

  6. Lead zirconate titanate fiber/polymer composites prepared by a replication process

    SciTech Connect

    Waller, D.J.; Safari, A. ); Card, R.J.; O'Toole, M.P. )

    1990-11-01

    The woven replication process was used to fabricate lead zirconate titanate (PZT)/polymer composites with 1-3, 2-3, and 3-3 connectivities by starting with novoloid-derived carbon fiber, woven fabric, and nonwoven felt templates, respectively. Activated carbon-fiber template material was impregnated with PZT by soaking it in a solution containing stoichiometric amounts of dissolved lead, zirconium, titanium, and niobium ions. Heat treatment burned out the carbon, leaving a PZT replica with the same form as the template material. Replicas were sintered in a controlled atmosphere and back-filled with an epoxy polymer to form final composites. This method, which is believed to be adaptable for mass production, is capable of producing composites and extremely fine microstructures. Woven composite samples have fiber tow diameters of 200 to 250 {mu}m and spacings between tows of about 150 to 250 {mu}m. Average d{sub 33} = 90 pC/N, g{sub 33} = 211 mV {center dot} m/N, and d{sub h}g{sub h} hydrophone figure of merit of 2100 {times} 10{sup {minus}15} m{sup 2}/N values are reported for woven PZT/polymer composites.

  7. Transverse piezoelectric coefficient measurement of flexible lead zirconate titanate thin films

    SciTech Connect

    Dufay, T.; Guiffard, B.; Seveno, R.; Thomas, J.-C.

    2015-05-28

    Highly flexible lead zirconate titanate, Pb(Zr,Ti)O{sub 3} (PZT), thin films have been realized by modified sol-gel process. The transverse piezoelectric coefficient d{sub 31} was determined from the tip displacement of bending-mode actuators made of PZT cantilever deposited onto bare or RuO{sub 2} coated aluminium substrate (16 μm thick). The influence of the thickness of ruthenium dioxide RuO{sub 2} and PZT layers was investigated for Pb(Zr{sub 0.57}Ti{sub 0.43})O{sub 3}. The modification of Zr/Ti ratio from 40/60 to 60/40 was done for 3 μm thick PZT thin films onto aluminium (Al) and Al/RuO{sub 2} substrates. A laser vibrometer was used to measure the beam displacement under controlled electric field. The experimental results were fitted in order to find the piezoelectric coefficient. Very large tip deflections of about 1 mm under low voltage (∼8 V) were measured for every cantilevers at the resonance frequency (∼180 Hz). For a given Zr/Ti ratio of 58/42, it was found that the addition of a 40 nm thick RuO{sub 2} interfacial layer between the aluminium substrate and the PZT layer induces a remarkable increase of the d{sub 31} coefficient by a factor of 2.7, thus corresponding to a maximal d{sub 31} value of 33 pC/N. These results make the recently developed PZT/Al thin films very attractive for both low frequency bending mode actuating applications and vibrating energy harvesting.

  8. Transverse piezoelectric coefficient measurement of flexible lead zirconate titanate thin films

    NASA Astrophysics Data System (ADS)

    Dufay, T.; Guiffard, B.; Thomas, J.-C.; Seveno, R.

    2015-05-01

    Highly flexible lead zirconate titanate, Pb(Zr,Ti)O3 (PZT), thin films have been realized by modified sol-gel process. The transverse piezoelectric coefficient d31 was determined from the tip displacement of bending-mode actuators made of PZT cantilever deposited onto bare or RuO2 coated aluminium substrate (16 μm thick). The influence of the thickness of ruthenium dioxide RuO2 and PZT layers was investigated for Pb(Zr0.57Ti0.43)O3. The modification of Zr/Ti ratio from 40/60 to 60/40 was done for 3 μm thick PZT thin films onto aluminium (Al) and Al/RuO2 substrates. A laser vibrometer was used to measure the beam displacement under controlled electric field. The experimental results were fitted in order to find the piezoelectric coefficient. Very large tip deflections of about 1 mm under low voltage (˜8 V) were measured for every cantilevers at the resonance frequency (˜180 Hz). For a given Zr/Ti ratio of 58/42, it was found that the addition of a 40 nm thick RuO2 interfacial layer between the aluminium substrate and the PZT layer induces a remarkable increase of the d31 coefficient by a factor of 2.7, thus corresponding to a maximal d31 value of 33 pC/N. These results make the recently developed PZT/Al thin films very attractive for both low frequency bending mode actuating applications and vibrating energy harvesting.

  9. Microwave emission from lead zirconate titanate induced by impulsive mechanical load

    NASA Astrophysics Data System (ADS)

    Aman, A.; Majcherek, S.; Hirsch, S.; Schmidt, B.

    2015-10-01

    This paper focuses on microwave emission from Lead zirconate titanate Pb [ZrxTi1-x] O3 (PZT) induced by mechanical stressing. The mechanical stress was initiated by impact of a sharp tungsten indenter on the upper surface of PZT ceramic. The sequences of microwave and current impulses, which flew from indenter to electric ground, were detected simultaneously. The voltage between the upper and lower surface of ceramic was measured to obtain the behavior of mechanical force acting on ceramic during the impact. It was found that the amplitude, form, and frequency of measured microwave impulses were different by compression and restitution phase of impact. Two different mechanisms of electron emission, responsible for microwave impulse generation, were proposed based on the dissimilar impulse behavior. The field emission from tungsten indenter is dominant during compression, whereas ferroemission dominates during restitution phase. Indeed, it was observed that the direction of the current flow, i.e., sign of current impulses is changed by transitions from compression to restitution phase of impact. The observed dissimilar behavior of microwave impulses, caused by increasing and decreasing applied force, can be used to calculate the contact time and behavior of mechanical force during mechanical impact on ceramic surface. It is shown that the generation of microwave impulses exhibits high reproducibility, impulse intensity, a low damping factor, and high mechanical failure resistance. Based on these microwave emission properties of PZT, the development of new type of stress sensor with spatial resolution of few microns becomes possible.

  10. Strength Properties of Aged Poled Lead Zirconate Titanate Subjected to Electromechanical Loadings

    SciTech Connect

    Zhang, Kewei; Zeng, Fan W; Wang, Hong; Lin, Hua-Tay

    2012-01-01

    Electric field and aging time are two important factors that affect the mechanical strength and long-term reliability of lead zirconate titanate or PZT actuators. In the present work, a commercial PZT-5A aged four years was examined using ball-on-ring (BoR) mechanical testing under coupled electric fields. The electric field range of -3E{sub c} to +3E{sub c} (E{sub c}, coercive electric field) was studied (i.e., -3E{sub c}, -E{sub c}, 0, +E{sub c}, +2E{sub c}, and +3E{sub c}) with a controlled electric loading path. A Weibull distribution was used to interpret the mechanical strength data. With an electric field preloaded from 0 to -3E{sub c}, it was found that subsequent increases in the electric field resulted in an asymmetrical V-shaped curve of mechanical strength against the electric field. The bottom of the V curve was located near the zero electric field level. Microscopy analysis showed that pores were the strength limiter for the tested PZT under electromechanical loadings.

  11. A statistical model approximation for perovskite solid-solutions: a Raman study of lead-zirconate- titanate single crystal

    SciTech Connect

    Frantti, Johannes; Fujioka, Y; Puretzky, Alexander A; Xie, Y; Glazer, A

    2013-01-01

    Lead titanate (PbTiO3) is a classical example of a ferroelectric perovskite oxide illustrating a displacive phase transition accompanied by a softening of a symmetry-breaking mode. The underlying assumption justifying the soft-mode theory is that the crystal is macroscopically sufficiently uniform so that a meaningful free energy function can be formed. In contrast to PbTiO3, experimental studies show that the phase transition behaviour of lead-zirconate-titanate solid solution (PZT) is far more subtle. Most of the studies on the PZT system have been dedicated to ceramic or powder samples, in which case an unambiguous soft-mode study is not possible, as modes with different symmetries appear together. Our Raman scattering study on titanium-rich PZT single crystal shows that the phase transitions in PZT cannot be described by a simple soft-mode theory. In strong contrast to PbTiO3, splitting of transverse E-symmetry modes reveals that there are different locally-ordered regions. The role of crystal defects, random distribution of Ti and Zr at the B- cation site and Pb ions shifted away from their ideal positions, dictates the phase transition mechanism. A statistical model explaining the observed peak splitting and phase transformation to a complex state with spatially varying local order in the vicinity of the morphotropic phase boundary is given.

  12. Piezoelectric and Dielectric Performance of Poled Lead Zirconate Titanate Subjected to Electric Cyclic Fatigue

    SciTech Connect

    Wang, Hong; Matsunaga, Tadashi; Lin, Hua-Tay; Mottern, Alexander M; Wereszczak, Andrew A

    2012-01-01

    Poled lead zirconate titanate (PZT) material as a single-layer plate was tested using piezodilatometer under electric cyclic loading in both unipolar and bipolar modes. Their responses were evaluated using unipolar and bipolar measurements on the same setup. Mechanical strain and charge density or polarization loops exhibited various variations when the material was cycled to more than 10^8 cycles. Important quantities including loop amplitude, hysteresis, switchable polarization, coercive field have been characterized accordingly under corresponding measurement conditions. At the same time, offset polarization and bias electric field of the material were observed to be changed and the trend was found to be related to the measurement condition also. Finally, the piezoelectric and dielectric coefficients were analyzed and their implications to the application of interest have been discussed.

  13. Substrate Clamping Effects on Irreversible Domain Wall Dynamics in Lead Zirconate Titanate Thin Films

    SciTech Connect

    Griggio, Flavio; Jesse, Stephen; Kumar, Amit; Ovchinnikov, Oleg S; Kim, H.; Jackson, T. N.; Damjanovic, Dragan; Kalinin, Sergei V; Trolier-Mckinstry, Susan E

    2012-01-01

    The role of long-range strain interactions on domain wall dynamics is explored through macroscopic and local measurements of nonlinear behavior in mechanically clamped and released polycrystalline lead zirconate-titanate (PZT) films. Released films show a dramatic change in the global dielectric nonlinearity and its frequency dependence as a function of mechanical clamping. Furthermore, we observe a transition from strong clustering of the nonlinear response for the clamped case to almost uniform nonlinearity for the released film. This behavior is ascribed to increased mobility of domain walls. These results suggest the dominant role of collective strain interactions mediated by the local and global mechanical boundary conditions on the domain wall dynamics. The work presented in this Letter demonstrates that measurements on clamped films may considerably underestimate the piezoelectric coefficients and coupling constants of released structures used in microelectromechanical systems, energy harvesting systems, and microrobots.

  14. Internal Friction and Dielectric Measurements in Lead Zirconate Titanate Ferroelectric Ceramics

    NASA Astrophysics Data System (ADS)

    Bourim, El Mostafa; Tanaka, Hidehiko; Gabbay, Maurice; Fantozzi, Gilbert

    2000-09-01

    Elastic modulus (Young’s modulus M and shear modulus G) and internal friction Q-1 are measured as a function of temperature from {-}180{\\degC} to 500°C in undoped lead zirconate titanate (PZT) ferroelectric ceramics in the range of kHz and low frequencies (0.1 to 1 Hz). New phase transition temperatures at the morphotropic zone at low temperatures are determined from the elastic modulus minimum. Permittivity \\varepsilon and dielectric loss \\tan(δ) are measured in the frequency range of 20 Hz to 10 kHz. Both mechanical and electrical measurements allow the observation of relaxation peaks in the ferroelectric phase. The Arrhenius plots of all these results show that it is possible to investigate these relaxation processes using both experimental techniques.

  15. Fatigue and failure responses of lead zirconate titanate multilayer actuator under unipolar high-field electric cycling

    SciTech Connect

    Zeng, Fan W; Wang, Hong; Lin, Hua-Tay

    2013-01-01

    Lead zirconate titanate (PZT) multilayer actuators with an interdigital electrode design were studied under high electric fields (3 and 6 kV/mm) in a unipolar cycling mode. A 100 Hz sine wave was used in cycling. Five specimens tested under 6 kV/mm failed from 3.8 10^5 to 7 10^5 cycles, whereas three other specimens tested under 3 kV/mm were found to be still functional after 10^8 cycles. Variations in piezoelectric and dielectric responses of the tested specimens were observed during the fatigue test, depending on the measuring and cycling conditions. Selected fatigued and damaged actuators were characterized using an impedance analyzer or small signal measurement. A scanning acoustic microscope also was employed as a nondestructive tool to detect the presence of defects. Failed plates were subsequently sectioned, and the extensive cracks and porous regions were observed to be across the PZT layers. The results from this study have demonstrated that the high-field cycling can accelerate the fatigue of PZT stacks as long as the partial discharge is controlled. The small signal measurement can also be integrated into the large signal measurement to characterize the fatigue response of PZT stacks in a more comprehensive basis. The former can further serve as an experimental method to monitor the behavior of PZT stacks.

  16. EPDM composite membranes modified with cerium doped lead zirconate titanate

    NASA Astrophysics Data System (ADS)

    Zaharescu, T.; Dumitru, A.; Lungulescu, M. E.; Velciu, G.

    2016-01-01

    This study was performed on γ-irradiated ethylene-propylene diene terpolymer (EPDM) loaded with lead zirconate titanate. The inorganic phase has a perovskite structure with general formula Pb(Zr0.65-xCexTi0.35)O3. The three composites with different Ce dopant concentrations revealed the stabilization activity of filler against oxidation proved by chemiluminescence investigation in respect to pristine polymer. The presence of cerium low concentrations in the solid lead zirconate titanate nanoparticles causes significant slowing of oxidation rate during radiation exposure. The improvement in the stabilization feature of filler is correlated with the existence of traps, whose interaction with free radicals assumes medium energy due to their convenient depth.

  17. A circular array transducer for photoacoustic imaging by using piezoelectric single crystal lead magnesium niobate-lead zirconate titanate

    NASA Astrophysics Data System (ADS)

    Cao, Yonggang; Ha, Kanglyeol; Kim, Moojoon; Kang, Hyunwook; Oh, Jung-Hwan; Kim, Jungsoon

    2015-07-01

    The ultrasound transducers of which center frequencies are lower than 10 MHz are commonly used in low frequency photoacoustic (PA) imaging systems. However, the improvement of their sensitivity is still needed to detect weak PA signals. In this study, a circular array transducer was constructed by using 120 needle hydrophones made of piezoelectric single crystal lead magnesium niobate-lead zirconate titanate (PMN-PZT). The needle hydrophone was designed to have high sensitivity and wide bandwidth through the Krimtholz-Leedom-Matthaei (KLM) simulation of receiving impulse response. The sensitivity of the fabricated PMN-PZT hydrophone was compared with a commercial poly(vinylidene fluoride) (PVDF) needle hydrophone. The usefulness of the circular array transducer was demonstrated by applying it to a PA system for obtaining images.

  18. Study of the characteristics of a piezoelectric lead zirconate titanate radiation detector using a pulsed xenon source

    SciTech Connect

    Miyachi, Takashi; Fujii, Masayuki; Hasebe, Nobuyuki; Okudaira, Osamu; Takechi, Seiji; Kurozumi, Atsuma; Morinaga, Shinya; Uno, Takefumi; Shibata, Hiromi; Kobayashi, Masanori; Murakami, Takeshi; Uchihori, Yukio; Okada, Nagaya

    2010-05-15

    The detector characteristics of piezoelectric lead zirconate titanate (PZT) were studied by directly irradiating a multilayered PZT detector with 400 MeV/n xenon ions. An extracted beam was processed with a rotating slit. Thus, passed through {approx}10{sup 3} xenon ions were available for 50 to 250 {mu}s. The effect of polarization on the output signal was discussed, and the optimal electrode configuration was determined. The output signal appeared as an isolated pulse whose amplitude was qualitatively understood by the Bethe-Bloch formula. However, the calculated and the observed values differed depending on the rotation speed of the slit. A process that can explain the differences is presented here. The output signal appearing beyond the range of 400 MeV/n xenon ion beam was discussed. The sensitivity was compared with that obtained with hypervelocity collision of dust.

  19. Study of the characteristics of a piezoelectric lead zirconate titanate radiation detector using a pulsed xenon source

    NASA Astrophysics Data System (ADS)

    Miyachi, Takashi; Fujii, Masayuki; Hasebe, Nobuyuki; Okudaira, Osamu; Takechi, Seiji; Kurozumi, Atsuma; Morinaga, Shinya; Uno, Takefumi; Shibata, Hiromi; Kobayashi, Masanori; Murakami, Takeshi; Uchihori, Yukio; Okada, Nagaya

    2010-05-01

    The detector characteristics of piezoelectric lead zirconate titanate (PZT) were studied by directly irradiating a multilayered PZT detector with 400 MeV/n xenon ions. An extracted beam was processed with a rotating slit. Thus, passed through ˜103 xenon ions were available for 50 to 250 μs. The effect of polarization on the output signal was discussed, and the optimal electrode configuration was determined. The output signal appeared as an isolated pulse whose amplitude was qualitatively understood by the Bethe-Bloch formula. However, the calculated and the observed values differed depending on the rotation speed of the slit. A process that can explain the differences is presented here. The output signal appearing beyond the range of 400 MeV/n xenon ion beam was discussed. The sensitivity was compared with that obtained with hypervelocity collision of dust.

  20. In situ cell detection using piezoelectric lead zirconate titanate-stainless steel cantilevers

    NASA Astrophysics Data System (ADS)

    Yi, Jeong W.; Shih, Wan Y.; Mutharasan, R.; Shih, Wei-Heng

    2003-01-01

    We have investigated piezoelectric lead zirconate titanate (PZT)-stainless steel cantilevers as real-time in-water cell detectors using yeast cells as a model system. Earlier studies have shown that mass changes of a cantilever can be detected by monitoring the resonance frequency shift. In this study, two PZT-stainless steel cantilevers with different sensitivities were used to detect the presence of yeast cells in a suspension. The stainless steel cantilever tip was coated with poly-L-lysine that attracted yeast cells from the suspension, and immobilized them on the cantilever surface. After immersing the poly-L-lysine coated tip in a yeast suspension, the flexural resonance frequency of the cantilever was monitored with time. The flexural resonance frequency decreased with time in agreement with the optical micrographs that showed increasing amount of adsorbed yeast cells with time. The resonance frequency shifts are further shown to be consistent with both the mass of immobilized cells on the poly-L-lysine coated stainless steel surface and that deduced from the optical micrographs. Furthermore, under the present experimental conditions where the cell diffusion distance is smaller than the linear dimension of the adsorption area, it is shown that the rate of resonance frequency shift is linear with the cell concentration and the rate of resonance frequency shift can be used to quantify the cell concentration.

  1. Investigation of the additive induced doping effects in gelcast soft lead zirconate titanate ceramics

    SciTech Connect

    Guo Dong; Cai Kai; Li Longtu; Gui Zhilun

    2009-09-01

    Due to the high sensitivity of the electrical properties of electronic ceramics to various factors, knowledge about the possible influence of the processing procedure on their electrical performance is critical for applying a new technique to the fabrication of the materials. In this study, various electrical parameters, complex impedance spectra, ferroelectric hysteresis loops, and microstructures of soft lead zirconate titanate (PZT) ceramics formed by the gelcasting technique from suspensions with various dispersants were investigated in comparison with those of the conventional dry pressed ones. We found that the sodium ion, which is the main cation in many commercial surfactants, exhibited obvious hard doping effects; thus causing deteriorated performance of the gelcast PZT ceramics. While a certain impurity ion introduced by a dispersant was also found to induce soft doping characteristics and improve the electrical performance of the materials. The results suggest that the doping effects of the metal ions or impurities introduced by the dispersants, or other additives, should be generally considered for applying a wet processing technique to forming multicomponent electronic ceramics.

  2. Structural health monitoring of multi-spot welded joints using a lead zirconate titanate based active sensing approach

    NASA Astrophysics Data System (ADS)

    Yao, Ping; Kong, Qingzhao; Xu, Kai; Jiang, Tianyong; Huo, Lin-sheng; Song, Gangbing

    2016-01-01

    Failures of spot welded joints directly reduce the load capacity of adjacent structures. Due to their complexity and invisibility, real-time health monitoring of spot welded joints is still a challenge. In this paper, a lead zirconate titanate (PZT) based active sensing approach was proposed to monitor the structural health of multi-spot welded joints in real time. In the active sensing approach, one PZT transducer was used as an actuator to generate a guided stress wave, while another one, as a sensor, detected the wave response. Failure of a spot welded joint reduces the stress wave paths and attenuates the wave propagation energy from the actuator to the sensor. A total of four specimens made of dual phase steel with spot welds, including two specimens with 20 mm intervals of spot welded joints and two with 25 mm intervals, were designed and fabricated for this research. Under tensile tests, the spot welded joints successively failed, resulting in the PZT sensor reporting decreased received energy. The energy attenuations due to the failures of joints were clearly observed by the PZT sensor signal in both the time domain and frequency domain. In addition, a wavelet packet-based spot-weld failure indicator was developed to quantitatively evaluate the failure condition corresponding to the number of failed joints.

  3. Microwave emission from lead zirconate titanate induced by impulsive mechanical load

    SciTech Connect

    Aman, A.; Majcherek, S.; Hirsch, S.; Schmidt, B.

    2015-10-28

    This paper focuses on microwave emission from Lead zirconate titanate Pb [Zr{sub x}Ti{sub 1−x}] O{sub 3} (PZT) induced by mechanical stressing. The mechanical stress was initiated by impact of a sharp tungsten indenter on the upper surface of PZT ceramic. The sequences of microwave and current impulses, which flew from indenter to electric ground, were detected simultaneously. The voltage between the upper and lower surface of ceramic was measured to obtain the behavior of mechanical force acting on ceramic during the impact. It was found that the amplitude, form, and frequency of measured microwave impulses were different by compression and restitution phase of impact. Two different mechanisms of electron emission, responsible for microwave impulse generation, were proposed based on the dissimilar impulse behavior. The field emission from tungsten indenter is dominant during compression, whereas ferroemission dominates during restitution phase. Indeed, it was observed that the direction of the current flow, i.e., sign of current impulses is changed by transitions from compression to restitution phase of impact. The observed dissimilar behavior of microwave impulses, caused by increasing and decreasing applied force, can be used to calculate the contact time and behavior of mechanical force during mechanical impact on ceramic surface. It is shown that the generation of microwave impulses exhibits high reproducibility, impulse intensity, a low damping factor, and high mechanical failure resistance. Based on these microwave emission properties of PZT, the development of new type of stress sensor with spatial resolution of few microns becomes possible.

  4. Lead zirconate titanate cantilever for noncontact atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Miyahara, Y.; Fujii, T.; Watanabe, S.; Tonoli, A.; Carabelli, S.; Yamada, H.; Bleuler, H.

    1999-02-01

    Noncontact atomic force microscopy with frequency modulation detection is a promising technique for surface observation with true atomic resolution. The piezoelectric material itself can be an actuator and sensor of the oscillating probe simultaneously, without the need for additional electro-mechanical transducers or other measurement systems. A vertical resolution of 0.01 nm rms has been achieved using a microfabricated cantilever with lead zirconate titanate thin film in noncontact mode frequency modulation detection. The cantilever also has a sharpened pyramidal stylus with a radius of about 10 nm for noncontact atomic force microscopy.

  5. Local origin of macroscopic properties and patterning in Lead zirconate titanate films

    NASA Astrophysics Data System (ADS)

    Bintachitt, Patamas

    This thesis describes the preparation of high quality lead zirconate titanate (PZT) films, the nonlinearity in their dielectric and piezoelectric responses, as well as their patterning by reactive ion etching. One goal of the research was to obtain {001} oriented PZT films on Pt-coated Si substrates. In this work, PbTiO3 buffer layers were chosen due to good lattice matching with PZT films, and the strong propensity for development of {001} orientation. The pyrolysis, crystallization steps, and lead excess addition of PbTiO3 buffer layers deposition were investigated. Using a thin PbTiO3 buffer layer and controlled pyrolysis conditions allowed {100} oriented PZT films to be prepared. The PbTiO3 buffer layer can be used over a full wafer to provide orientation. Higher piezoelectric coefficients, e31,f of -14 and -10 C/m2 were achieved for {001} PZT thin films of 1.0 mum and 0.24 mum thickness, respectively using appropriate poling conditions. The local and global domain wall contributions were studied by piezoelectric nonlinearity and dielectric nonlinearity in both {001}-textured PZT films and PZT films with mixed {001} and {111} orientation. It was found that films over the thickness range probed showed Rayleigh-like behavior. 4 mum thick films were nearly uniform in their Rayleigh coefficient, suggesting that any heterogeneities in the response developed at lateral length scales below the resolution of the PFM measurement. In contrast, thinner films showed significantly more patchiness in their response, so that fluctuations in behavior developed at a lateral length scale on the order of 0.6 to 2.5 micron. These variations did not appear to be correlated directly with the surface topology. Finally, it is hypothesized that the same population of domain wall contributes to the local and global nonlinearity. Nanoindentation measurements were conducted in an attempt to distinguish 180° and non-180° domain wall motion in these films. Non-180° domain walls can be

  6. Fabrication and modeling of bismuth titanate-PZT ceramic transducers for high temperature applications

    NASA Astrophysics Data System (ADS)

    Reinhardt, B.; Searfass, C.; Cyphers, R.; Sinding, K.; Pheil, C.; Tittmann, B.

    2013-01-01

    Utilization of a spray-on deposition technique of ferroelectric bismuth titanate (Bi4Ti3O12) composites has a competitive advantage to standard ultrasonic transducers. These can conform to curved surfaces, can operate at high temperature (Curie-Weiss temperature 685 °C) and are mechanically well-coupled to a substrate. However, an issue with many high temperature transducers such as bismuth titanate ceramics is that they have relatively low transduction efficiency, i.e. d33 is about 12-14 pC/F in Bi4Ti3O12 versus 650 pC/F in PZT-5H. It is a common conception that high-temperature capability comes at the cost of electro-mechanical coupling. It will be shown that the high temperature capability of bismuth-titanate-PZT composite transducers using the spray-on deposition technique previously developed, improves the electro-mechanical coupling while maintaining the high temperature performance and mechanical coupling. This material could provide advantages in harsh environments where high signal-to-noise ratios are needed.

  7. Luminescence studies of perovskite structured titanates: A review

    NASA Astrophysics Data System (ADS)

    Nag Bhargavi, G.; Khare, Ayush

    2015-06-01

    Apart from widely known dielectric and ferroelectric properties, the perovskite type materials also constitute a class of materials, which are recently investigated for their optical properties. These materials are being used for fabrication of various microelectronics and optoelectronic devices. Photoluminescence (PL), mechanoluminescence (ML) and thermoluminescence (TL) are such phenomena offering numerous applications in different fields like electro-optics, flat panel displays, LED technology, sensors, dynamic visualization etc. This paper briefly reviews the status and new progress in luminescence studies of ferroelectric materials like barium titanate (BT), barium zirconate titanate (BZT), calcium titanate (CT), calcium zirconate titanate (CZT), lead titanate (PT), lead zirconate titanate (PZT), etc., prepared through various methods.

  8. Lead zirconate titanate-based thick films for high-frequency focused ultrasound transducers prepared by electrophoretic deposition.

    PubMed

    Abellard, André-Pierre; Kuscer, Danjela; Grégoire, Jean-Marc; Lethiecq, Marc; Malic, Barbara; Levassort, Franck

    2014-03-01

    An electrophoretic deposition (EPD) process with high deposition rate was used to fabricate a curved piezoelectric thick film devoted to high-frequency transducers for medical imaging. Niobium-doped lead zirconate titanate (PZTNb) powder was stabilized in ethanol to prepare a suspension with high zeta potential and low conductivity. A gold layer, pad-printed and fired on a curved porous PZT substrate, was used as the working electrode for the deposition of the PZTNb thick film. This substrate was chosen because it has the required properties (acoustic impedance and attenuation) to be used directly as a backing for the high-frequency transducer, leading to a simplified process for transducer assembly with this integrated structure. PZT-Nb thick films were also deposited by EPD on flat gold-coated alumina substrates as a reference. The thickness of the films was between 20 and 35 μm, and their electromechanical performance was comparable to standard PZT bulk ceramics with a thickness coupling factor of 48%. For the curved thick film, the thickness coupling factor was slightly lower. The corresponding integrated structure was used to fabricate a transducer with a center frequency of 40 MHz and an f-number of 2.8. It was integrated into a realtime ultrasound scanner and used to image human forearm skin; the resulting images showed, for the first time, the efficacy of the EPD process for these imaging applications. PMID:24569258

  9. Active layers of high-performance lead zirconate titanate at temperatures compatible with silicon nano- and microelecronic devices

    NASA Astrophysics Data System (ADS)

    Bretos, Iñigo; Jiménez, Ricardo; Tomczyk, Monika; Rodríguez-Castellón, Enrique; Vilarinho, Paula M.; Calzada, M. Lourdes

    2016-02-01

    Applications of ferroelectric materials in modern microelectronics will be greatly encouraged if the thermal incompatibility between inorganic ferroelectrics and semiconductor devices is overcome. Here, solution-processable layers of the most commercial ferroelectric compound - morphotrophic phase boundary lead zirconate titanate, namely Pb(Zr0.52Ti0.48)O3 (PZT) - are grown on silicon substrates at temperatures well below the standard CMOS process of semiconductor technology. The method, potentially transferable to a broader range of Zr:Ti ratios, is based on the addition of crystalline nanoseeds to photosensitive solutions of PZT resulting in perovskite crystallization from only 350 °C after the enhanced decomposition of metal precursors in the films by UV irradiation. A remanent polarization of 10.0 μC cm-2 is obtained for these films that is in the order of the switching charge densities demanded for FeRAM devices. Also, a dielectric constant of ~90 is measured at zero voltage which exceeds that of current single-oxide candidates for capacitance applications. The multifunctionality of the films is additionally demonstrated by their pyroelectric and piezoelectric performance. The potential integration of PZT layers at such low fabrication temperatures may redefine the concept design of classical microelectronic devices, besides allowing inorganic ferroelectrics to enter the scene of the emerging large-area, flexible electronics.

  10. Active layers of high-performance lead zirconate titanate at temperatures compatible with silicon nano- and microelecronic devices

    PubMed Central

    Bretos, Iñigo; Jiménez, Ricardo; Tomczyk, Monika; Rodríguez-Castellón, Enrique; Vilarinho, Paula M.; Calzada, M. Lourdes

    2016-01-01

    Applications of ferroelectric materials in modern microelectronics will be greatly encouraged if the thermal incompatibility between inorganic ferroelectrics and semiconductor devices is overcome. Here, solution-processable layers of the most commercial ferroelectric compound ─ morphotrophic phase boundary lead zirconate titanate, namely Pb(Zr0.52Ti0.48)O3 (PZT) ─ are grown on silicon substrates at temperatures well below the standard CMOS process of semiconductor technology. The method, potentially transferable to a broader range of Zr:Ti ratios, is based on the addition of crystalline nanoseeds to photosensitive solutions of PZT resulting in perovskite crystallization from only 350 °C after the enhanced decomposition of metal precursors in the films by UV irradiation. A remanent polarization of 10.0 μC cm−2 is obtained for these films that is in the order of the switching charge densities demanded for FeRAM devices. Also, a dielectric constant of ~90 is measured at zero voltage which exceeds that of current single-oxide candidates for capacitance applications. The multifunctionality of the films is additionally demonstrated by their pyroelectric and piezoelectric performance. The potential integration of PZT layers at such low fabrication temperatures may redefine the concept design of classical microelectronic devices, besides allowing inorganic ferroelectrics to enter the scene of the emerging large-area, flexible electronics. PMID:26837240

  11. Active layers of high-performance lead zirconate titanate at temperatures compatible with silicon nano- and microeletronic [corrected] devices.

    PubMed

    Bretos, Iñigo; Jiménez, Ricardo; Tomczyk, Monika; Rodríguez-Castellón, Enrique; Vilarinho, Paula M; Calzada, M Lourdes

    2016-01-01

    Applications of ferroelectric materials in modern microelectronics will be greatly encouraged if the thermal incompatibility between inorganic ferroelectrics and semiconductor devices is overcome. Here, solution-processable layers of the most commercial ferroelectric compound--morphotrophic phase boundary lead zirconate titanate, namely Pb(Zr0.52Ti0.48)O3 (PZT)--are grown on silicon substrates at temperatures well below the standard CMOS process of semiconductor technology. The method, potentially transferable to a broader range of Zr:Ti ratios, is based on the addition of crystalline nanoseeds to photosensitive solutions of PZT resulting in perovskite crystallization from only 350 °C after the enhanced decomposition of metal precursors in the films by UV irradiation. A remanent polarization of 10.0 μC cm(-2) is obtained for these films that is in the order of the switching charge densities demanded for FeRAM devices. Also, a dielectric constant of ~90 is measured at zero voltage which exceeds that of current single-oxide candidates for capacitance applications. The multifunctionality of the films is additionally demonstrated by their pyroelectric and piezoelectric performance. The potential integration of PZT layers at such low fabrication temperatures may redefine the concept design of classical microelectronic devices, besides allowing inorganic ferroelectrics to enter the scene of the emerging large-area, flexible electronics. PMID:26837240

  12. Energy harvesting from vertically aligned PZT nanowire arrays

    NASA Astrophysics Data System (ADS)

    Malakooti, Mohammad H.; Zhou, Zhi; Sodano, Henry A.

    2016-04-01

    In this paper, a nanostructured piezoelectric beam is fabricated using vertically aligned lead zirconate titanate (PZT) nanowire arrays and its capability of continuous power generation is demonstrated through direct vibration tests. The lead zirconate titanate nanowires are grown on a PZT thin film coated titanium foil using a hydrothermal reaction. The PZT thin film serves as a nucleation site while the titanium foil is used as the bottom electrode. Electromechanical frequency response function (FRF) analysis is performed to evaluate the power harvesting efficiency of the fabricated device. Furthermore, the feasibility of the continuous power generation using the nanostructured beam is demonstrated through measuring output voltage from PZT nanowires when beam is subjected to a sinusoidal base excitation. The effect of tip mass on the voltage generation of the PZT nanowire arrays is evaluated experimentally. The final results show the great potential of synthesized piezoelectric nanowire arrays in a wide range of applications, specifically power generation at nanoscale.

  13. Converse mode piezoelectric coefficient for lead zirconate titanate thin film with interdigitated electrode

    NASA Astrophysics Data System (ADS)

    Chidambaram, N.; Balma, D.; Nigon, R.; Mazzalai, A.; Matloub, R.; Sandu, C. S.; Muralt, P.

    2015-04-01

    The use of interdigitated electrodes (IDEs) in conjunction with ferroelectric thin films shows many attractive features for piezoelectric MEMS applications. In this work, growth of {1 0 0}-textured lead zirconate titanate (PZT) thin films was achieved on insulating MgO buffered, oxidized silicon substrates. IDEs were fabricated by lift-off techniques and cantilevers were formed by dicing. The deflection upon application of a sweeping voltage was measured as large signal response in parallel to the ferroelectric polarization (PV loop). Likewise, the small signal piezoelectric response was measured in parallel to the capacitance-voltage (CV) measurement. In this way, a complete picture of the ferroelectric-piezoelectric element was obtained. From the deflection, the in-plane piezoelectric stress in the PZT thin film was derived and, from this, the effective piezoelectric coefficients. For the latter, two types were defined: an engineering type corresponding to the average value along the IDE, which can directly be compared to coefficient of a parallel plate electrode (PPE) capacitor and a second one that approximately yields the idealized coefficient governing between the electrode fingers. The IDE structures were experimentally compared with PPE structures of identical film thickness. The resulting coefficients were of opposite sign, as expected. In spite of a much better polarization loop, the IDE device showed a lower average piezoelectric stress. The estimated peak value between the fingers was about the same as in the PPE device, corresponding to about 20 C m-2. Nevertheless, the result is very promising for cases where compressive piezoelectric stresses are required and for preventing cracking due to large piezoelectric tensile stresses in PPE systems.

  14. Formation and properties of porous films of lead zirconate titanate

    NASA Astrophysics Data System (ADS)

    Seregin, D. S.; Vorotilov, K. A.; Sigov, A. S.; Zubkova, E. N.; Abdullaev, D. A.; Kotova, N. M.; Vishnevskiy, A. S.

    2015-03-01

    The processes of formation and the properties of porous ceramic lead zirconate titanate films have been considered. The porous structure formed by thermal destruction of polyvinylpyrrolidone (PVP) with the molecular weight 29000 makes it possible to increase the cracking-free film thickness (by a factor of approximately two for one deposition at 20 wt % PVP; in this case, the volume porosity is 33%). An increase in the porosity decreases the permittivity ɛ; at 20 wt % PVP, ɛ = 432-456 depending on the film thickness. These values are less than those in nonporous films by a factor of more than two. An increase in the porosity is accompanied by an increase in the remanent polarization in the films. However, the hysteresis loop shape changes in the region of saturation polarization.

  15. Neutron irradiation effects on domain wall mobility and reversibility in lead zirconate titanate thin films

    SciTech Connect

    Graham, Joseph T.; Brennecka, Geoff L.; Ihlefeld, Jon F.; Ferreira, Paulo; Small, Leo; Duquette, David; Apblett, Christopher; Landsberger, Sheldon

    2013-03-28

    The effects of neutron-induced damage on the ferroelectric properties of thin film lead zirconate titanate (PZT) were investigated. Two sets of PbZr{sub 0.52}Ti{sub 0.48}O{sub 3} films of varying initial quality were irradiated in a research nuclear reactor up to a maximum 1 MeV equivalent neutron fluence of (5.16 {+-} 0.03) Multiplication-Sign 10{sup 15} cm{sup -2}. Changes in domain wall mobility and reversibility were characterized by polarization-electric field measurements, Rayleigh analysis, and analysis of first order reversal curves (FORC). With increasing fluence, extrinsic contributions to the small-signal permittivity diminished. Additionally, redistribution of irreversible hysterons towards higher coercive fields was observed accompanied by the formation of a secondary hysteron peak following exposure to high fluence levels. The changes are attributed to the radiation-induced formation of defect dipoles and other charged defects, which serve as effective domain wall pinning sites. Differences in damage accumulation rates with initial film quality were observed between the film sets suggesting a dominance of pre-irradiation microstructure on changes in macroscopic switching behavior.

  16. Fundamental Study of Cavitation Sensors Fabricated with Lead Zirconate Titanate Film Deposited by Hydrothermal Method: Analysis and Consideration of Output Signal from the Sensor

    NASA Astrophysics Data System (ADS)

    Seto, Yuki; Kawashima, Norimichi; Kuribayashi Kurosawa, Minoru; Takeuchi, Shinichi

    2008-05-01

    Small cavitation sensors were developed with hydrothermally synthesized lead zirconate titanate (PZT) on the outer surface of the Ti cylinder. Output signals from the fabricated cavitation sensor were analyzed in frequency domain with changing applied voltage to the Langevin transducer of the ultrasound exposure system. Frequency components from 1 to 5 MHz included in the output signal from the cavitation sensor were measured as the cavitation signal in order to distinguish the harmonic components from acoustic cavitation from those by nonlinear propagation in water. Broadband integrated voltage can be calculated by integrating harmonic components from 1 to 5 MHz included in the output signal from the cavitation sensor.

  17. Effects of Pb5Ge3O11 on pyroelectric lead-zirconate-titanate thick films deposited on silicon substrate by electrophoresis deposition

    NASA Astrophysics Data System (ADS)

    Gui Wu, Chuan; Peng, Qiang Xiang; Sun, Xiang Yu; Meng, Jia; Yao, Shuai; Luo, Wen Bo; Li Zhang, Wan

    2015-04-01

    The effects of Pb5Ge3O11 (PGO) sintering additive on the sintering temperature (Ts) and pyroelectric properties of 1 × 1 mm2 lead-zirconate-titanate (PZT) thick films on Pt/Ti/SiO2/Si substrates were studied. The pattern of PGO-added PZT thick films were formed directly by electrophoresis deposition (EPD). The PGO percentage and Ts were optimized at the range from 0 to 9 wt % and 700 to 900 °C, respectively. The energy dispersive spectrometer (EDS) results showed that the diffusion between Si and PZT were weaken gradually as the Ts decreased. The sintered PZT films sintered at 800 °C with 3 wt % PGO exhibited room-temperature pyroelectric coefficient (Pc) of 1.73 × 10-8 C/(cm2·K), figure of merit for detectivity (FD) of 1.9 × 10-5 Pa-0.5, permittivity of 330 and dielectric loss of 1.5% (1 kHz), respectively. These results demonstrate that the directly patterned PGO-added PZT thick films fabricated by EPD show potential application in MEMS detectors.

  18. Improved dielectric properties of lead zirconate titanate thin films deposited on metal foils with LaNiO3 buffer layers

    NASA Astrophysics Data System (ADS)

    Zou, Q.; Ruda, H. E.; Yacobi, B. G.

    2001-02-01

    Improved dielectric properties of lead zirconate titanate (PZT) films deposited on a variety of foils using buffer layers are reported. Foils include titanium, stainless steel, and nickel with LaNiO3(LNO) buffer layers which were prepared by sol-gel processing. High dielectric constant (330 for stainless steel, 420 for titanium, and 450 for nickel foils), low dielectric loss (<2.2% for titanium and 8% for stainless steel), symmetric ferroelectric C-V characteristics and P-E curves were obtained. The LNO layers are shown to provide an effective diffusion barrier for Ni and Cr and to restrict oxide layer formation (i.e., TiOx or NiOx) between the PZT film and the metallic foils during annealing in air.

  19. Pressure, temperature, and electric field dependence of phase transformations in niobium modified 95/5 lead zirconate titanate

    SciTech Connect

    Dong, Wen D.; Carlos Valadez, J.; Gallagher, John A.; Jo, Hwan R.; Lynch, Christopher S.; Sahul, Raffi; Hackenberger, Wes

    2015-06-28

    Ceramic niobium modified 95/5 lead zirconate-lead titanate (PZT) undergoes a pressure induced ferroelectric to antiferroelectric phase transformation accompanied by an elimination of polarization and a volume reduction. Electric field and temperature drive the reverse transformation from the antiferroelectric to ferroelectric phase. The phase transformation was monitored under pressure, temperature, and electric field loading. Pressures and temperatures were varied in discrete steps from 0 MPa to 500 MPa and 25 °C to 125 °C, respectively. Cyclic bipolar electric fields were applied with peak amplitudes of up to 6 MV m{sup −1} at each pressure and temperature combination. The resulting electric displacement–electric field hysteresis loops were open “D” shaped at low pressure, characteristic of soft ferroelectric PZT. Just below the phase transformation pressure, the hysteresis loops took on an “S” shape, which split into a double hysteresis loop just above the phase transformation pressure. Far above the phase transformation pressure, when the applied electric field is insufficient to drive an antiferroelectric to ferroelectric phase transformation, the hysteresis loops collapse to linear dielectric behavior. Phase stability maps were generated from the experimental data at each of the temperature steps and used to form a three dimensional pressure–temperature–electric field phase diagram.

  20. Preparation and Characterization of PZT Thin Films

    SciTech Connect

    Bose, A.; Sreemany, M.; Bhattacharyya, D. K.; Sen, Suchitra; Halder, S. K.

    2008-07-29

    In analogy with Piezoelectric Wafer Active Sensors (PWAS), Lead Zirconate Titanate (PZT) thin films also seem to be promising for Structural Health Monitoring (SHM) due to a number of reasons. Firstly, PZT thin films with well oriented domains show enhanced piezoelectric response. Secondly, PWAS requires comparatively large voltage leading to a demand for thin PZT films (<< {mu}m in thickness) for low voltage operation at {<=}10 V. This work focuses on two different aspects: (a) growing oriented PZT thin films in ferroelectric perovskite phase in the range of (80-150) nm thickness on epitaxial Si/Pt without a seed layer and (b) synthesizing perovskite phase in PZT thin films on Corning glass 1737 using a seed layer of TiO{sub x} (TiO{sub x} thickness ranging between 30 nm to 500 nm)

  1. Domain wall motion effect on the anelastic behavior in lead zirconate titanate piezoelectric ceramics

    NASA Astrophysics Data System (ADS)

    Bourim, El Mostafa; Tanaka, Hidehiko; Gabbay, Maurice; Fantozzi, Gilbert; Cheng, Bo Lin

    2002-05-01

    Three undoped lead zirconate titanate (PZT) ceramics were prepared with compositions close to the morphotropic phase boundary: Pb(Zr0.50Ti0.50)O3, Pb(Zr0.52Ti0.48)O3, and Pb(Zr0.54Ti0.46)O3. Internal friction Q-1 and shear modulus G were measured versus temperature from 20 °C to 500 °C. Experiments were performed on an inverted torsional pendulum at low frequencies (0.1, 0.3, and 1 Hz). The ferroelectric-paraelectric phase transition results in a peak (P1) of Q-1 correlated with a sharp minimum M1 of G. Moreover the Q-1(T) curves show two relaxation peaks called R1 and R2 respectively, correlated with two shear modulus anomalies called A1 and A2 on the G(T) curves. The main features of the transition P1 peak are studied, they suggest that its behavior is similar to the internal friction peaks associated with martensitic transformation. The relaxation peak, R1 and R2 are both attributed to motion of domain walls (DWs), and can be analyzed by thermal activated process described by Arrhenius law. The R2 peak is demonstrated to be due to the interaction of domain walls and oxygen vacancies because it depends on oxygen vacancy concentration and electrical polarization. However, the R1 peak is more complex; its height is found to be increased as stress amplitude and heating rate increase. It seems that the R1 peak is influenced by three mechanisms: (i) relaxation due to DW-point defects interaction, (ii) variation of domain wall density, and (iii) domain wall depinning from point defect clusters.

  2. Evaluation of antibacterial properties of Barium Zirconate Titanate (BZT) nanoparticle

    PubMed Central

    Mohseni, Simin; Aghayan, Mahdi; Ghorani-Azam, Adel; Behdani, Mohammad; Asoodeh, Ahmad

    2014-01-01

    So far, the antibacterial activity of some organic and inorganic compounds has been studied. Barium zirconate titanate [Ba(ZrxTi1-x)O3] (x = 0.05) nanoparticle is an example of inorganic materials. In vitro studies have provided evidence for the antibacterial activity of this nanoparticle. In the current study, the nano-powder was synthesized by sol-gel method. X-ray diffraction showed that the powder was single-phase and had a perovskite structure at the calcination temperature of 1000 °C. Antibacterial activity of the desired nanoparticle was assessed on two gram-positive (Staphylococcus aureus PTCC1431 and Micrococcus luteus PTCC1625) and two gram-negative (Escherichia coli HP101BA 7601c and clinically isolated Klebsiella pneumoniae) bacteria according to Radial Diffusion Assay (RDA). The results showed that the antibacterial activity of BZT nano-powder on both gram-positive and gram-negative bacteria was acceptable. The minimum inhibitory concentration of this nano-powder was determined. The results showed that MIC values for E. coli, K. pneumoniae, M. luteus and S. aureus were about 2.3 μg/mL, 7.3 μg/mL, 3 μg/mL and 12 μg/mL, respectively. Minimum bactericidal concentration (MBC) was also evaluated and showed that the growth of E. coli, K. pneumoniae, M. luteus and S. aureus could be decreased at 2.3, 14, 3 and 18 μg/mL of BZT. Average log reduction in viable bacteria count in time-kill assay ranged between 6 Log10 cfu/mL to zero after 24 h of incubation with BZT nanoparticle. PMID:25763046

  3. Detection of indentation induced Fe-to-Afe phase transformation in lead zirconate titanate.

    SciTech Connect

    Baddorf, Arthur P.; Shin, Junsoo; Gogotsi, Yury G.; Buchheit, Thomas Edward; Watson, Chad Samuel; Kalinin, Sergei; Juliano, Thomas F.

    2005-08-01

    Instrumented indentation was combined with microscopy and spectroscopy analysis to investigate the local mechanically induced ferroelectric to anti-ferroelectric phase transformation of niobium-modified lead zirconate titanate 95/5. Indentation experiments to a depth of 2 {micro}m were performed using a Berkovich pyramidal three-sided diamond tip. Subsequent Raman spectroscopy and piezoelectric force microscopy revealed that indentation locally induced the ferroelectric to antiferroelectric phase transformation. Piezoelectric force microscopy demonstrated the ability to map the individual phases within and near indented regions on the niobium-modified lead zirconate titanate ceramics.

  4. Raman study of lead zirconate titanate under uniaxial stress

    SciTech Connect

    TALLANT, DAVID R.; SIMPSON, REGINA L.; GRAZIER, J. MARK; ZEUCH, DAVID H.; OLSON, WALTER R.; TUTTLE, BRUCE A.

    2000-04-01

    The authors used micro-Raman spectroscopy to monitor the ferroelectric (FE) to antiferroelectric (AFE) phase transition in PZT ceramic bars during the application of uniaxial stress. They designed and constructed a simple loading device, which can apply sufficient uniaxial force to transform reasonably large ceramic bars while being small enough to fit on the mechanical stage of the microscope used for Raman analysis. Raman spectra of individual grains in ceramic PZT bars were obtained as the stress on the bar was increased in increments. At the same time gauges attached to the PZT bar recorded axial and lateral strains induced by the applied stress. The Raman spectra were used to calculate an FE coordinate, which is related to the fraction of FE phase present. The authors present data showing changes in the FE coordinates of individual PZT grains and correlate these changes to stress-strain data, which plot the macroscopic evolution of the FE-to-AFE transformation. Their data indicates that the FE-to-AFE transformation does not occur simultaneously for all PZT grains but that grains react individually to local conditions.

  5. Phase Formation in PZT Phosphorus-Doped Ceramics

    SciTech Connect

    Celi, L. A.; Caballero, A. C.; Villegas, M.; Moure, C.; Fernandez, J. F.; Eiras, J. A.

    2009-04-19

    The surface modification of lead zirconate titanate (PZT) ceramics with phosphate ester leaves a phosphorus residue absorbed onto the particle surface. During the sintering processes, this surface layer reacts with the PZT to form lead-rich compounds, such as Pb{sub 3}(PO{sub 4}){sub 2} and Pb{sub 4}(P{sub 2}O{sub 9}). The formation of such a compounds may be the responsible for the grain growth inhibition observed in PZT-modified ceramics, as well as the lead loss reduction.

  6. Hyperfine interaction measurements on ceramics: PZT revisited

    NASA Astrophysics Data System (ADS)

    Guarany, Cristiano A.; Araújo, Eudes B.; Silva, Paulo R. J.; Saitovitch, Henrique

    2007-02-01

    The solid solution of PbZr 1-xTi xO 3, known as lead-zirconate titanate (PZT), was probably one of the most studied ferroelectric materials, especially due to its excellent dielectric, ferroelectric and piezoelectric properties. The highest piezoelectric coefficients of the PZT are found near the morphotropic phase boundary (MPB) (0.46⩽ x⩽0.49), between the tetragonal and rhombohedral regions of the composition-temperature phase diagram. Recently, a new monoclinic phase near the MPB was observed, which can be considered as a “bridge” between PZT's tetragonal and rhombohedral phases. This work is concerned with the study of the structural properties of the ferroelectric PZT (Zr/Ti=52/48, 53/47) by hyperfine interaction (HI) measurements obtained from experiments performed by using the nuclear spectroscopy time differential perturbed angular correlation (TDPAC) in a wide temperature range.

  7. Dielectric Properties of PVDF/PZT

    SciTech Connect

    Zak, A. Khorsand; Chen, Gan Wee; Majid, W. H. Abd.

    2011-03-30

    Poly(vinylidene fluoride)/ lead zirconate titanate nanocomposite (PVDF/PZT-NPs) were successfully prepared by mixing fine Pb(Zr{sub 0.52}, Ti{sub 0.48})O{sub 3} nanoparticles (PZT-NPs) into a PVDF solution under ultrasonication. The mixture was spin coated onto glass substrate and then annealed at 80 deg. C. X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) were used to characterize the structure and properties of the obtained thin-film nanocomposites. The nanocomposites exhibited good dielectric stability over a wide frequency range.

  8. Influence of combined external stress and electric field on electric properties of 0.5% Fe-doped lead zirconate titanate ceramics

    SciTech Connect

    Suchanicz, J.; Kim-Ngan, N.-T. H.; Konieczny, K.; Jankowska-Sumara, I.; Sitko, D.; Goc-Jaglo, D.; Balogh, A. G.

    2009-11-01

    Influence of uniaxial pressure (0-1000 bars) applied parallel to or perpendicularly to the ac or dc electric field (in one-dimensional or two-dimensional manner) on dielectric and ferroelectric properties of hard lead zirconate titanate (PZT) ceramics were investigated. The experimental results revealed that applying uniaxial pressure leads to a reduction in the peak intensity of the electric permittivity (epsilon), of the frequency dispersion as well as of the dielectric hysteresis. Moreover, with increasing pressure the peak intensity of epsilon becomes diffused and shifts to a higher temperature. It was also found that simultaneous application of uniaxial pressure and electric field (perpendicular to each other) in the poling process improves the ferroelectric properties. This indeed indicates new possibility for poling materials with a high coercive field and/or high electric conductivity. The effects of uniaxial load are weaker than that obtained for soft PZT ceramics. It was concluded that applying uniaxial pressure induces similar effects as increasing the Ti ion concentration in PZT system. The obtained results were interpreted through Cochran soft mode and domain switching processes under applying of pressure.

  9. Development of a straightness measurement and compensation system with multiple right-angle reflectors and a lead zirconate titanate-based compensation stage

    SciTech Connect

    Liu, Chien-Hung; Chen, Jui-Hung; Teng, Yun-Feng

    2009-11-15

    This paper presents a real-time straightness measurement and compensation system with an optical straightness measurement system and a single-axis flexure-hinge type lead zirconate titanate (PZT)-based compensation stage. The optical straightness measurement system consists of a He-Ne laser, a quadrant photodiode detector, and five right-angle reflectors. Multiple laser beam reflections between the right-angle reflectors increase the sensitivity of the straightness measurement by a factor of 6. The right-angle reflectors can be moved by the flexure-hinge type PZT-based compensation stage that is actuated by a PZT actuator to ensure that the laser beam is always projected onto the center of the quadrant detector. These two systems are integrated and fixed on a scanning stage. The resolution of the straightness measurement system is 0.1 {mu}m. Using the real-time straightness compensation system, the straightness error of the scanning stage is fed back to the control system. The compensated straightness error of the scanning stage system was reduced from 6.5 {mu}m to less than 1 {mu}m.

  10. Oriented lead zirconate titanate thin films: Characterization of film crystallization

    SciTech Connect

    Voigt, J.A.; Tuttle, B.A.; Headley, T.J.; Eatough, M.O.; Lamppa, D.L.; Goodnow, D.

    1993-11-01

    Film processing temperature and time was varied to characterize the pyrochlore-to-perovskite crystallization of solution-derived PZT 20/80 thin films. 3000 {Angstrom} thick films were prepared by spin deposition using <100> single crystal MgO as substrate. By controlled rapid thermal processing, films at different stages in the perovskite crystallization process were prepared with the tetragonal PZT 20/80 phase being <100>/<001> oriented relative to the MgO surface. An activation energy for the conversion process of 326 kJ/mole was determined by use of an Arrhenius expression using rate constants found by application of the method of Avrami. Activation energy for formation of the PZT 20/80 perovskite phase of the solution-derived films compared favorably with that calculated from data by Kwok and Desu for sputter-deposited 3500 {Angstrom} thick PZT 55/45 films. Similarity in activation energies indicates that the energetics of the conversion process are not strongly dependent on the method used for film deposition.

  11. Cantilever Type Lead Zirconate Titanate Microactuator Utilizing Ruthenium Oxide

    NASA Astrophysics Data System (ADS)

    Lee, Sun-Ho; Jeon, Min-Seok; Hong, Kyung-Il; Lee, Jin-Won; Kim, Chang-Kyung; Choi, Duck-Kyun

    2000-05-01

    A new and simple cantilever type Pb(Zr, Ti)O3 [PZT] microactuator was fabricated by adopting RuO2. The RuO2 has reasonably good conductivity and stiffness and it can replace the double layer of electrode and supporting layer to a single layer in a cantilever beam. The RuO2, PZT and Al thin films were deposited on the Si substrate. The patterning of the Al was carried out by a lithography process and etched with a chemical wet etchant. The etching of PZT and RuO2 were performed by a reactive ion etching system. The Si was etched isotropically to form a cantilever beam. The fabricated cantilever beam consists of Al, PZT and RuO2, and the thicknesses of the films are 0.40, 0.25 and 0.70 μm, respectively. The beams were from 140 μm to 275 μm in length and all of them were 60 μm wide. Driving tilt angles of the cantilever beams were almost proportional to the applied voltages.

  12. Thickness dependence of the poling and current-voltage characteristics of paint films made up of lead zirconate titanate ceramic powder and epoxy resin

    NASA Astrophysics Data System (ADS)

    Egusa, Shigenori; Iwasawa, Naozumi

    1995-11-01

    A specially prepared paint made up of lead zirconate titanate (PZT) ceramic powder and epoxy resin was coated on an aluminum plate and was cured at room temperature, thus forming the paint film of 25-300 μm thickness with a PZT volume fraction of 53%. The paint film was then poled at room temperature, and the poling behavior was determined by measuring the piezoelectric activity as a function of poling field. The poling behavior shows that the piezoelectric activity obtained at a given poling field increases with an increase in the film thickness from 25 to 300 μm. The current-voltage characteristic of the paint film, on the other hand, shows that the increase in the film thickness leads not only to an increase in the magnitude of the current density at a given electric field but also to an increase in the critical electric field at which the transition from the ohmic to space-charge-limited conduction takes place. This fact indicates that the amount of the space charge of electrons injected into the paint film decreases as the film thickness increases. Furthermore, comparison of the current-voltage characteristic of the paint film with that of a pure epoxy film reveals that the space charge is accumulated largely at the interface between the PZT and epoxy phases in the paint film. On the basis of this finding, a model is developed for the poling behavior of the paint film by taking into account a possible effect of the space-charge accumulation and a broad distribution of the electric field in the PZT phase. This model is shown to give an excellent fit to the experimental data of the piezoelectric activity obtained here as a function of poling field and film thickness.

  13. Optical absorption in ion-implanted lead lanthanum zirconate titanate ceramics

    SciTech Connect

    Seager, C.H.; Land, C.E.

    1984-08-15

    Optical absorption measurements have been performed on unmodified and on ion-implanted lead lanthanum zirconate titanate ceramics using the photothermal deflection spectroscopy technique. Bulk absorption coefficients depend on the average grain size of the material while the absorption associated with the ion-damaged layers does not. The damage-induced surface absorptance correlates well with the photosensitivity observed in implanted PLZT devices, supporting earlier models for the enhanced imaging efficiency of the materials.

  14. Photo-reduction of silver salts on highly heterogeneous lead zirconate titanate

    NASA Astrophysics Data System (ADS)

    Jones, P. M.; Dunn, S.

    2007-05-01

    This paper presents the work undertaken to determine the influences on the photo-induced growth of silver nanoclusters on the surfaces of lead zirconate titanate thin films. The lead zirconate titanate films were grown on indium tin oxide coated glass. They exhibited a highly textured surface and can be treated as wide bandgap semiconductors that exhibit ferroelectric behaviour. We show that there is a preferential deposition of silver metal on the ferroelectric films that is related not only to the polarization state of the ferroelectric domains but also to the surface defects such as grain boundaries and defects within the film. The greatest deposition rates are found to occur at grain boundaries where there is an approximately 40:1 ratio of silver clusters when compared to the native positive domains exhibited by the lead zirconate titanate. We propose that the mechanism for cluster growth depends on the availability, and diffusion rate, of electrons into the growing cluster and that the clusters grow from a discrete nucleation point. We also show that the growth of a monolayer of silver is sufficient to prevent the formation of electron-hole pairs by blocking the UV irradiation and that the silver nanoparticles are readily removed from the surface using an ultrasonic bath leading to a possible new method of manufacturing metal nanoparticles.

  15. The effect of a hydrostatic pressure induced phase transformation on the unipolar electrical response of Nb modified 95/5 lead zirconate titanate

    NASA Astrophysics Data System (ADS)

    Valadez, J. C.; Sahul, R.; Alberta, E.; Hackenberger, W.; Lynch, C. S.

    2012-01-01

    Niobium doped lead zirconate titanate (95/5 NbPZT) undergoes a hydrostatic pressure induced ferroelectric rhombohedral to antiferroelectric orthorhombic phase transformation (FE-AFE). This work reports on the experimental characterization of the large field dielectric response to unipolar electric field as it passes through the forward and reverse FE-AFE transformations. The poled ceramic was hydrostatically depoled by driving the FE-AFE phase transformation and stress-strain and stress-electric displacement responses were measured. After this initial characterization, specimens of 95/5 NbPZT were subjected to unipolar electric field loading at different hydrostatic pressure levels. Electric field was varied from zero to 1 MV/m at a series of fixed pressure levels between zero and 550 MPa. This resulted in minor hysteresis loops with the area inside the loops dependent on both pressure and electric field amplitude. Two different slopes were taken from the D-E loops, identified as the small field and large field slopes. Each changed with pressure and displayed distinct jumps at the forward and reverse FE-AFE phase transformations. The area within the loops in the ferroelectric regime, attributed to domain wall motion, increased as pressure was increased and dropped abruptly as the material passed through the pressure induced phase transformation.

  16. Microstructural and optical characterization of PZT nanopowder prepared at low temperature

    NASA Astrophysics Data System (ADS)

    Ghasemifard, M.; Hosseini, S. M.; Khorsand Zak, A.; Khorrami, Gh. H.

    2009-01-01

    Lead zirconate titanate (PZT) nanopowders were synthesized by the metal organic and salt precursor's sol-gel combustion technique. Single-phase perovskite PZT powders were obtained after heat treatment at temperature of 500 °C. The effects of calcination temperature on lattice parameters and tetragonality of PZT powders have been discussed. The average particles size is estimated to be around 70-80 nm by SEM observations. The absorption coefficient ( α) and the band-gap energy ( Eg) of the perovskite oxide have been estimated using Fourier transform infrared (FTIR) spectroscopy.

  17. Low Temperature Sintering of PZT

    NASA Astrophysics Data System (ADS)

    Medesi, A.; Greiner, T.; Benkler, M.; Megnin, C.; Hanemann, T.

    2014-11-01

    This paper describes the fabrication and characterization of lead zirconate titanate (PZT) films fired in a liquid-phase sintering process at 900 °C in air. In detail the manufacturing of piezoelectric multilayers with internal pure silver (Tm = 961 °C) electrodes are reported. The feasibility of ten sintering aids in two different volume fractions was investigated for a commercial hard PZT powder (PIC 181, PI Ceramics) with respect to density, microstructure, mechanical behaviour, and piezoelectric properties. Li2O, Li2CO3, PbO, MnO2, V2O5, CuO, Bi2O3, the eutectic mixtures Cu2O·PbO and PbO·WO3 and the ternary system Li2CO3·Bi2O3·CuO (LBCu) have been tested as liquid phase sintering aids. The combination of PZT with LBCu showed the best results. With 5 vol.% LBCu an average relative density of 97% and a characteristic breaking strength of 77 MPa was achieved. Composition of PZT with 2 vol.% LBCu exhibits the highest averaged piezoelectrical charge constant (d33) of 181 pC/N.

  18. Power harvesting using PZT ceramics embedded in orthopedic implants.

    PubMed

    Chen, Hong; Liu, Ming; Jia, Chen; Wang, Zihua

    2009-09-01

    Battery lifetime has been the stumbling block for many power-critical or maintenance-free real-time embedded applications, such as wireless sensors and orthopedic implants. Thus a piezoelectric material that could convert human motion into electrical energy provides a very attractive solution for clinical implants. In this work, we analyze the power generation characteristics of stiff lead zirconate titanate (PZT) ceramics and the equivalent circuit through extensive experiments. Our experimental framework allows us to explore many important design considerations of such a PZT-based power generator. Overall we can achieve a PZT element volume of 0.5 x 0.5 x 1.8 cm, which is considerably smaller than the results reported so far. Finally, we outline the application of our PZT elements in a total knee replacement (TKR) implant. PMID:19812004

  19. Bistable optical information storage using antiferroelectric-phase lead lanthanum zirconate titanate ceramics

    SciTech Connect

    Land, C.E.

    1988-11-01

    A recently discovered photostorage effect in antiferroelectric-phase (AFE-phase) lead lanthanum zirconate titanate (PLZT) compositions appears to be particularly applicable to binary optical information storage. The basis for bistable optical information storage is that exposure to near-UV or visible light shifts the electric field threshold of the phase transition between the field-induced ferroelectric (FE) phase and the stable AFE phase in the direction of the initial AFE /yields/ FE phase transition. Properties of this photoactivated shift of the FE /yields/ AFE phase transition, including preliminary photosensitivity measurements and photostorage mechanisms, are presented. Photosensitivity enhancement by ion implantation is also discussed.

  20. Compact piezoelectric micromotor with a single bulk lead zirconate titanate stator

    NASA Astrophysics Data System (ADS)

    Yan, Liang; Lan, Hua; Jiao, Zongxia; Chen, Chin-Yin; Chen, I.-Ming

    2013-04-01

    The advance of micro/nanotechnology promotes the development of micromotors in recent years. In this article, a compact piezoelectric ultrasonic micromotor with a single bulk lead zirconate titanate stator is proposed. A traveling wave is generated by superposition of bending modes with 90° phase difference excited by d15 inverse piezoelectric effects. The operating principle simplifies the system structure significantly, and provides a miniaturization solution. A research prototype with the size of 0.75× 0.75×1.55 mm is developed. It can produce start-up torque of 0.27μNmand maximum speed of 2760 r/min at 14RMS.

  1. Strong magnetoelectric coupling at microwave frequencies in metallic magnetic film/lead zirconate titanate multiferroic composites

    NASA Astrophysics Data System (ADS)

    Pettiford, C.; Lou, J.; Russell, L.; Sun, N. X.

    2008-03-01

    Strong magnetoelectric coupling was observed at microwave frequencies in metallic magnetic film/lead zirconate titanate [Pb(Zr,Ti)O3] multiferroic composites, in which the magnetic films were either FeCoB or FeGaB with relatively high saturation magnetostriction constants between 40 and 70ppm and narrow ferromagnetic resonance linewidths of ˜20Oe at 10GHz. Large electrostatically induced ferromagnetic resonance frequency shifts of 50-110MHz at ˜2.3GHz were observed. These metallic magnetic film/Pb(Zr ,Ti)O3 multiferroic composites with large electrostatic tunability of the ferromagnetic resonance frequency provide great opportunities for integrated microwave multiferroic devices.

  2. Programmable diffractive optical element using a multichannel lanthanum-modified lead zirconate titanate phase modulator

    NASA Astrophysics Data System (ADS)

    Thomas, James A.; Fainman, Yeshaiahu

    1995-07-01

    We introduce a programmable diffractive optical element based on an electro-optic phased array implemented with a multichannel lanthanum-modified lead zirconate titanate phase modulator. The design and fabrication procedures are outlined, along with an experimental demonstration of the device. Experimental results from a 16-channel device operating with a 2 pi voltage of 300 V demonstrate selective beam steering. The programmable diffractive optical element allows for efficient, high-speed high-resolution random-access optical beam steering over a continuous scanning range.

  3. Electron-microscope study of lanthanum-doped lead zirconate-titanate solid solutions

    SciTech Connect

    Ishchuk, V.M.; Presnyakova, O.V.

    1985-12-01

    This paper examines the structure of specimens of lanthanumdoped lead zirconate-titanate solid solutions in the hysteresis region of the phase diagram, using transmission electron microscopy. The electron-microscopic images of PLZT ceramic of composition display an unusual diffraction contrast. An analysis of the images obtained for different orientations of the cleavages of specimens of composition indicate that the second-phase inclusions are cylindrical in the main. The authors hypothesize that the inclusions are a ferroelectric phase in an antiferroelectric matrix.

  4. Dielectric loss peak due to platinum electrode porosity in lead zirconate titanate thin-film capacitors

    NASA Astrophysics Data System (ADS)

    Jung, D. J.; Dawber, M.; Ruediger, A.; Scott, J. F.; Kim, H. H.; Kim, Kinam

    2002-09-01

    Impedance spectroscopy measurements were carried out in situ on lead zirconate titanate capacitors 1.2×1.2 μm2 in size on a Samsung 4 Mbit 6 in, wafer. We show here that large dielectric loss appears at low frequencies, which is a constriction effect due to the porosity of the platinum electrode. Porous platinum electrodes facilitate an oxygen electrode reaction. The effect may be removed by annealing the platinum electrode at moderate temperature (300 °C). Such an anneal should thus be considered an essential step in the fabrication of a ferroelectric thin-film capacitor on Pt.

  5. EFFECTS OF ELECTRIC FIELD ON THE BIAXIAL STRENGTH OF POLED PZT

    SciTech Connect

    Wang, Hong; Wereszczak, Andrew A

    2008-01-01

    The mechanical integrity of piezoelectric ceramics plays a crucial role in the performance and design of lead zirconate titanate (PZT) piezo stack actuators especially as PZT actuators become physically larger and are sought to operate under harsher conditions. The reliable design of such systems demands additional consideration of a number of issues that include electro-mechanical coupling as well as strength-size scaling. This study addresses some of those issues through the use of ball-on-ring (BoR) equibiaxial flexure strength tests of two PZT piezo ceramics. The BoR biaxial flexure tests were conducted with two PZT materials under different electric fields. Fracture surfaces and failure initiations were analyzed using optical and scanning electronic microscopy. The effects of electric fields on the two-parameter Weibull distribution are discussed. These results will serve as input data for future probabilistic reliability analysis of multilayer PZT piezo actuators.

  6. A role of BNLT compound addition on structure and properties of PZT ceramics

    NASA Astrophysics Data System (ADS)

    Jaita, P.; Watcharapasorn, A.; Jiansirisomboon, S.

    2010-09-01

    In this research, effects of lead-free bismuth sodium lanthanum titanate (BNLT) addition on structure and properties of lead zirconate titanate (PZT) ceramics were investigated. PZT ceramics with addition of 0.1-3.0 wt%BNLT were fabricated by a solid-state mixed oxide method and sintering at 1050-1200 °C for 2 h to obtain dense ceramics with at least 96% of theoretical density. X-ray diffraction indicated that complete solid solution occurred for all compositions. Phase identification showed both tetragonal and rhombohedral perovskite structure of PZT with no BNLT phase detected. Scanning electron micrographs of fractured PZT/BNLT ceramics showed equiaxed grain shape with both transgranular and intergranular fracture modes. Addition of BNLT was also found to reduce densification and effectively limited grain growth of PZT ceramic. Optimum Hv and KIC values were found to be 4.85 GPa and 1.56 MPa.m 1/2 for PZT/0.5 wt%BNLT sample. Among PZT/BNLT samples, room temperature dielectric constant seemed to be improved with increasing BNLT content. The maximum piezoelectric coefficient values were observed in pure PZT ceramic and were slightly decreased in BNLT-added samples. Small reduction of remanent polarization and coercive field in hysteresis loops was observed in BNLT-added samples, indicating a slightly suppressed ferroelectric interaction in this material system.

  7. Experimental characterization of PZT fibers using IDE electrodes

    NASA Astrophysics Data System (ADS)

    Wyckoff, Nicholas; Ben Atitallah, Hassene; Ounaies, Zoubeida

    2016-04-01

    Lead zirconate titanate (PZT) fibers are mainly used in active fiber composites (AFC) where they are embedded in a polymer matrix. Interdigitated electrodes (IDE) along the direction of the fibers are used to achieve planar actuation, hereby exploiting the d33 coefficient of PZT. When embedded in the AFC, the PZT fibers are subjected to mechanical loading as well as non-uniform electric field as a result of the IDEs. Therefore, it is important to characterize the electrical and electromechanical behavior of these fibers ex-situ using the IDE electrodes to assess the impact of nonuniform electric field on the properties of the fibers. For that reason, this work aims at quantifying the impact of IDE electrodes on the electrical and electromechanical behavior of PZT fibers, which is necessary for their successful implementation in devices like AFC. The tested fibers were purchased from Advanced Cerametrics and they have an average diameter of 250 micrometers. The IDE electrodes were screen printed on an acrylic substrate. The PZT fibers were subjected to frequency sweeps at low voltages to determine permittivity for parallel and interdigitated electrodes. The piezoelectric e33 constant is determined from electromechanical testing of PZT fibers in parallel electrodes to compare the electromechanical behavior for PZT in bulk and fiber form. The dielectric constant and e33 were found to be lower for the IDE and parallel electrodes compared to bulk but comparable to results published in literature.

  8. Model for ion-implantation-induced improvements of photoferroelectric imaging in lead lanthanum zirconate titanate ceramics

    SciTech Connect

    Peercy, P.S.; Land, C.E.

    1980-11-01

    Studies of photoferroelectric image storage in H-, He-, and, more recently, Ar-implanted /(PLZT) lead lanthanum zirconate titanate reveal that the photosensitivity can be significantly increased by ion implantation into the image storage surface. For example, the photosensitivity after implantation with 5 x 10/sup 14/ 500-keV Ar/cm/sup 2/ is increased by about three orders of magnitude over that of unimplanted PLZT. The increase in photosensitivity results from a decrease in dark conductivity and changes in the photoconductivity of the implanted layer. We present a phenomenological model which describes the photosensitivity enhancement obtained by ion implantation. This model takes into account both light- and ion- implantation-induced changes in conductivity and gives quantitative agreement with the measured changes in the coercive voltage with near-UV light intensity for ion-implantated PLZT.

  9. Effects of ion implantation on the photoferroelectric properties of lead lanthanum zirconate titanate ceramics

    SciTech Connect

    Land, C.E.; Peercy, P.S.

    1981-01-01

    Earlier studies of Ar-, Ar + Ne- and Ar + Ne + He- implanted ferroelectric-phase lead lanthanum zirconate titanate (PLZT) ceramics indicate that ion implantation can increase the intrinsic (near-uv) photoferroelectric sensitivity by more than four orders of magnitude compared to that of unimplanted PLZT. More recent studies involving implantation of chemically active ions, e.g., Al and Cr, indicate that the absorption spectrum of the implanted region can be extended from the near-uv to the visible, and that the extrinsic (visible-light) photoferroelectric sensitivity can be improved substantially with respect to that of PLZT implanted with inert ions. The results of these studies are reviewed and photographic sensitivities of Ar-, Ar + Ne-, Ar + Ne + He-, Al-, Cr-, Fe-, and Fe + Ne- implanted PLZT at both near-uv and visible-light wavelengths are compared with the sensitivities of other image storage media.

  10. Photoluminescence of barium titanate and barium zirconate in multilayer disordered thin films at room temperature.

    PubMed

    Moreira, M L; Gurgel, M F C; Mambrini, G P; Leite, E R; Pizani, P S; Varela, J A; Longo, E

    2008-09-25

    The emission of wide band photoluminescence showed a synergic effect on barium zirconate and barium titanate thin films in alternate multilayer system at room temperature by 488 nm exiting wavelength. The thin films obtained by spin-coating were annealed at 350, 450, and 550 degrees C for 2 h. The X-ray patterns revealed the complete separation among the BaTiO3 and BaZrO3 phases in the adjacent films. Visible and intense photoluminescence was governed by BaZrO3 thin films in the multilayer system. Quantum mechanics calculations were used in order to simulate ordered and disordered thin films structures. The disordered models, which were built by using the displacement of formers and modifier networks, showed a different symmetry in each system, which is in accordance with experimental photoluminescence emission, thus allowing to establish a correlation among the structural and optical properties of these multilayered systems. PMID:18593105

  11. Processing and structural properties of random oriented lead lanthanum zirconate titanate thin films

    SciTech Connect

    Araújo, E.B.; Nahime, B.O.; Melo, M.; Dinelli, F.; Tantussi, F.; Baschieri, P.; Fuso, F.; Allegrini, M.

    2015-01-15

    Highlights: • Pyrochlore phase crystallizes near the bottom film-electrode interface. • PLZT films show a non-uniform microstrain and crystallite size in depth profile. • Complex grainy structure leads to different elastic modulus at the nanoscale. - Abstract: Polycrystalline lead lanthanum zirconate titanate (PLZT) thin films have been prepared by a polymeric chemical route to understand the mechanisms of phase transformations and map the microstructure and elastic properties at the nanoscale in these films. X-ray diffraction, atomic force microscopy (AFM) and ultrasonic force microscopy (UFM) have been used as investigative tools. On one side, PLZT films with mixed-phase show that the pyrochlore phase crystallizes predominantly in the bottom film-electrode interface while a pure perovskite phase crystallizes in top film surface. On the contrary, pyrochlore-free PLZT films show a non-uniform microstrain and crystallite size along the film thickness with a heterogeneous complex grainy structure leading to different elastic properties at nanoscale.

  12. Mechanical behavior, properties and reliability of tin-modified lead zirconate titanate.

    SciTech Connect

    Watson, Chad Samuel

    2003-08-01

    The influences of temperature and processing conditions (unpoled or poled-depoled) on strength, fracture toughness and the stress-strain behavior of tin-modified lead zirconate titanate (PSZT) were evaluated in four-point bending. PSZT exhibits temperature-dependent non-linear and non-symmetric stress-strain behavior. A consequence of temperature dependent non-linearity is an apparent reduction in the flexural strength of PSZT as temperature increases. At room temperature the average stress in the outer-fiber of bend bars was 84 MPa, whereas, for specimens tested at 120 C the average failure stress was only 64 MPa. The load-carrying capacity, however, does not change with temperature, but the degree of deformation tolerated by PSZT prior to failure increased with temperature.

  13. Conformable amplified lead zirconate titanate sensors with enhanced piezoelectric response for cutaneous pressure monitoring

    NASA Astrophysics Data System (ADS)

    Dagdeviren, Canan; Su, Yewang; Joe, Pauline; Yona, Raissa; Liu, Yuhao; Kim, Yun-Soung; Huang, Yongan; Damadoran, Anoop R.; Xia, Jing; Martin, Lane W.; Huang, Yonggang; Rogers, John A.

    2014-08-01

    The ability to measure subtle changes in arterial pressure using devices mounted on the skin can be valuable for monitoring vital signs in emergency care, detecting the early onset of cardiovascular disease and continuously assessing health status. Conventional technologies are well suited for use in traditional clinical settings, but cannot be easily adapted for sustained use during daily activities. Here we introduce a conformal device that avoids these limitations. Ultrathin inorganic piezoelectric and semiconductor materials on elastomer substrates enable amplified, low hysteresis measurements of pressure on the skin, with high levels of sensitivity (~0.005 Pa) and fast response times (~0.1 ms). Experimental and theoretical studies reveal enhanced piezoelectric responses in lead zirconate titanate that follow from integration on soft supports as well as engineering behaviours of the associated devices. Calibrated measurements of pressure variations of blood flow in near-surface arteries demonstrate capabilities for measuring radial artery augmentation index and pulse pressure velocity.

  14. Ultra large deflection of thin PZT/aluminium cantilever beam

    NASA Astrophysics Data System (ADS)

    Seveno, Raynald; Guiffard, Benoit; Regoin, Jean-Pierre

    2015-04-01

    Flexible piezoelectric cantilever beam has been realized by depositing lead zirconate titanate (PZT) thin film (4.5 μm) by chemical solution deposition (CSD) onto very thin aluminium foil (16 μm). The tip deflection of the beam has been measured as a function of the frequency of the applied sinusoidal voltage to the PZT film for different amplitudes. Resonance curves have been compared to a classical model of an oscillating system under sinusoidal stress with a very good agreement. Despite of weak ferroelectric properties (remnant polarization: 13 μC/cm2), ultra-large deflection amplitudes have been measured under very moderate applied voltage values: 750 μm@10 V for quasi-static mode and 5 mm@10 V at the resonance frequency ( 12 Hz), which makes this PZT/aluminium composite film very promising for highly flexible actuation applications where large displacements are wanted.

  15. Microemulsion Synthesis of Nanoparticle PZT Powder

    NASA Astrophysics Data System (ADS)

    Amiriyan, M.; Nemati, Z. A.; Rahmanifar, M. S.; Ramesh, S.; Meenaloshini, S.; Tolouei, R.

    2011-01-01

    Nanocrystalline lead zirconate titanate (PZT) powders have been synthesized using microemulsion processing route. Microemulsion is one of the major processing techniques to synthesize a nanosize, homogenous, and almost agglomerate free ceramic powders. The ternary microemulsion system is consisted of cyclohexane as the oil phase, Triton X100 as the nonionic surfactant phase, and an aqueous phase containing 0.619 M Pb2+, 0.325 M Zr4+, and 0.3 M Ti4+, representing a Pb2+: Zr4+: Ti4+ molar ratio of 1:0.52:0.48. The ratio of these cations has been adjusted using Inductively Coupled Plasma (ICP) technique. After coprecipitation of metallic hydroxides by adding ammonia solution in microemulsion system, the PZT precursor was obtained. PZT powders have been prepared upon calcination of precursor at 800° C. Prepared powders was characterised using techniques such as X-ray diffraction, differential thermal analysis, and scanning electron microscopy. The characteristics of microemulsion processed powder is discussed, with emphasis on the presence of nano scaled PZT powder with a composition near to morphotropic phase boundary (MPB) without formation of any intermediate phases.

  16. Damage detection of concrete beam based on embedded PZT impedance transducer encapsulated by cement

    NASA Astrophysics Data System (ADS)

    Wang, Dansheng; Zhu, Hongping; Yuan, Junqiang; Li, Jinghui; Li, Yu

    2012-04-01

    Piezoelectric material, such as, Lead Zirconate Titanate (PZT) can be use as sensing and/or actuating element for structural health monitoring due to its direct and converse piezoelectric effects. In this study, several fabricated PZT impedance transducers encapsulated by cement were embedded into a plain concrete beam to detect the surface crack damage. By monitoring the electromechanical (EM) admittance spectra of the embedded transducers, the structural surface crack damage was investigated. From the experimental results it is found that the shape of the electrical admittance spectra curve of the embedded PZT transducers hardly changes before and after surface crack is of presence, and the EM admittance spectra exhibits tiny change in amplitude with the increase of crack depth, which indicate that the embedded PZT transducers into concrete are insensitive to surface crack damage.

  17. New Fabrication of High-Frequency (100-MHz) Ultrasound PZT Film Kerfless Linear Array

    PubMed Central

    Zhu, Benpeng; Chan, Ngai Yui; Dai, Jiyan; Shung, K. Kirk; Takeuchi, Shinichi; Zhou, Qifa

    2013-01-01

    The paper describes the design, fabrication, and measurements of a high-frequency ultrasound kerfless linear array prepared from hydrothermal lead zirconate titanate (PZT) thick film. The 15-µm hydrothermal PZT thick film with an area of 1 × 1 cm, obtained through a self-separation process from Ti substrate, was used to fabricate a 32-element 100-MHz kerfless linear array with photolithography. The bandwidth at −6 dB without matching layer, insertion loss around center frequency, and crosstalk between adjacent elements were measured to be 39%, −30 dB, and −15 dB, respectively. PMID:23549547

  18. Transducer loading effect on the performance of PZT-based SHM systems.

    PubMed

    Baptista, Fabricio Guimarães; Filho, Jozue Vieira

    2010-04-01

    In the last years, the piezoelectric transducers of lead zirconate titanate (PZT) have been widely used in structural health monitoring (SHM) systems based on the electromechanical (E/M) impedance technique. Although many studies indicate the successful use of PZT in damage detection, some practical considerations still have to be considered in real applications. In this work, the effect of the transducer loading caused by mechanical impedance of the host structure is analyzed using an equivalent electromechanical circuit. Tests were performed on structures with various sizes and the results show that the transducer loading significantly reduces the sensitivity of the system for detecting structural damages. PMID:20378455

  19. Passive vibration damping of carbon fiber reinforced plastic with PZT particles and SMA powder

    NASA Astrophysics Data System (ADS)

    Jung, Jaemin; Lee, Woo Il; Lee, Dasom; Park, Sungho; Moon, Sungnam

    2016-04-01

    Carbon fiber reinforced plastic (CFRP) has been used various industrial fields, because of high strength, light weight, corrosion resistance and other properties. In this study, lead zirconate titanate (PZT) ceramic particles which is one of typical piezoelectric material and shape memory alloy powder dispersed in CFRP laminate in order to improve the vibration damping by dissipating vibration energy quickly. The loss factor (tanδ) is measured in Dynamic mechanical analyzer (DMA) which is used to measure the viscoelastic behavior of a material to verify the change in vibration damping. The results show that there exists difference on vibration damping ability between CFRP with PZT ceramic particles and CFRP with SMA powder.

  20. Thin film multilayers of ferroelastic TiNi-ferroelectric PZT: Fabrication and characterization

    SciTech Connect

    Mercado, P.G.; Jardine, A.P.

    1994-12-31

    Heterostructure multilayers of ferroelastic TiNi coupled to thin film TiO{sub 2} and ferroelectric lead zirconate titanate (PZT) produces a smart material capable of performing both sensing and actuating functions. An important issue is the ability to generate the appropriate crystalline phases of each of the materials and to minimize the chemical interactions from the surrounding material. TiO{sub 2} and PZT thin films were deposited onto commercially available TiNi substrates by the sol-gel process. Minimum crystallization temperatures for the TiO{sub 2} phases and PZT perovskite phases were determined and characterized by X-ray diffraction (XRD). For testing of the properties of these mesoscale structures to occur, the mechanical and electrical properties of the individual components need to be characterized. The mechanical properties of the PZT thin film were characterized by Scanning Electron Microscopy and optical microscopy. Cracking and defects in the PZT were observed for thick films, however thin PZT films of 1 micron or less showed better mechanical integrity. The ferroelectric properties of the PZT thin films were smaller than for bulk PZT; this was likely associated with leakage currents caused by the mechanical imperfections of the films.

  1. Develop techniques for ion implantation of PLZT (lead-lanthanum-zirconate-titanate) for adaptive optics

    SciTech Connect

    Batishko, C.R.; Brimhall, J.L.; Pawlewicz, W.T.; Stahl, K.A.; Toburen, L.H.

    1987-07-01

    Research was conducted at Pacific Northwest Laboratory to develop high photosensitivity adaptive optical elements utilizing ion implanted lanthanum-doped lead-zirconate-titanate (PLZT). One centimeter square samples were prepared by implanting ferroelectric and anti-ferroelectric PLZT with a variety of species or combinations of species. These included Ne, O, Ni, Ne/Cr, Ne/Al, Ne/Ni, Ne/O, and Ni/O, at a variety of energies and fluences. An indium-tin oxide (ITO) electrode coating was designed to give a balance of high conductivity and optical transmission at near uv to near ir wavelengths. Samples were characterized for photosensitivity; implanted layer thickness, index of refraction, and density; electrode (ITO) conductivity; and in some cases, residual stress curvature. Thin film anti-ferroelectric PLZT was deposited in a preliminary experiment. The structure was amorphous with x-ray diffraction showing the beginnings of a structure at substrate temperatures of approximately 550/sup 0/C. This report summarizes the research and provides a sampling of the data taken during the report period.

  2. Thermal and mechanical effects on large field dielectric loss in lanthanum-doped lead zirconate titanate

    NASA Astrophysics Data System (ADS)

    Gallagher, John A.; Jo, Hwan Ryul; Lynch, Christopher S.

    2013-04-01

    Ferroelectric material losses in devices ranging from sonar transducers to energy harvesters result in the conversion of energy to heat. Under small amplitude sinusoidal drive, either electrical or mechanical, the losses are expressed in terms of a loss tangent. This study addressed the effects of temperature and bias stress on large field dielectric loss in the presence of thermal and mechanical loading in lanthanum-doped lead zirconate titanate, Pb0.92La0.08(Zr0.65Ti0.35)0.98O3 (PLZT 8/65/35). This loss is associated with domain wall motion. Large field dielectric loss was experimentally measured using a technique that matches the area within a unipolar electric displacement - electric field hysteresis loop to an equivalent area ellipse-shaped hysteresis loop. The results indicate that the dependence of dielectric loss on bias stress changes with the onset of a thermally induced transition to slim loop behavior. Stress causes the dielectric loss to increase at low temperature and decrease at high temperature. This is consistent with changes in remnant polarization and saturation of the unipolar electric field - electric displacement hysteresis loops.

  3. Oxalate co-precipitation synthesis of calcium zirconate and calcium titanate powders.

    SciTech Connect

    Hernandez-Sanchez, Bernadette A.; Tuttle, Bruce Andrew

    2009-06-01

    Fine powders of calcium zirconate (CaZrO{sub 3}, CZ) and calcium titanate (CaTiO{sub 3}, CT) were synthesized using a nonaqueous oxalate co-precipitation route from Ca(NO{sub 3}){sub 2}{center_dot}4 H{sub 2}O and group(IV) n-butoxides (Ti(OBu{sup n}){sub 4} or Zr(OBu{sup n}){sub 4}). Several reaction conditions and batch sizes (2-35 g) were explored to determine their influence on final particle size, morphology, and phase. Characterization of the as-prepared oxalate precursors, oven dried oxalate precursors (60-90 C), and calcined powders (635-900 C) were analyzed with TGA/DTA, XRD, TEM, and SEM. Densification and sintering studies on pressed CZ pellets at 1375 and 1400 C were also performed. Through the developed oxalate co-precipitation route, densification temperatures for CZ were lowered by 125 C from the 1500 C firing temperature required for conventional mixed oxide powders. Low field electrical tests of the CZ pellets indicated excellent dielectric properties with dielectric constants of {approx}30 and a dissipation factor of 0.0004 were measured at 1 kHz.

  4. Effect of composition and temperature on electric fatigue of La-doped lead zirconate titanate ceramics

    NASA Astrophysics Data System (ADS)

    Jiang, Q. Y.; Subbarao, E. C.; Cross, L. E.

    1994-06-01

    Composition and temperature of ferroelectric La-doped lead zirconate titanate ceramics influence its electric fatigue behavior, defined as the degradation of the electrical properties under the action of an ac field applied for a long time. Compositions of rhombohedral symmetry exhibit little or no fatigue compared with those of tetragonal and orthorhombic symmetry. At temperatures higher than the dielectric maximum, no fatigue effect was detected. Compositions close to phase boundaries (FE-AFE, FE-FE, or FE-PE) display significant fatigue behavior. Electric fatigue arises from the pinning of domains by space charges or injected carriers or from microcracking. The former (which are charge related) is accompanied by smaller strains and is recoverable by thermal and electrical treatment, while the latter (arising from microcracking) arises from large incompatible stresses between grains and is a permanent damage. The understanding of the mechanism of electric fatigue gained in the present study provides guidelines for enhancing the long-term reliability of devices based on ferroic materials.

  5. Conformable amplified lead zirconate titanate sensors with enhanced piezoelectric response for cutaneous pressure monitoring.

    PubMed

    Dagdeviren, Canan; Su, Yewang; Joe, Pauline; Yona, Raissa; Liu, Yuhao; Kim, Yun-Soung; Huang, YongAn; Damadoran, Anoop R; Xia, Jing; Martin, Lane W; Huang, Yonggang; Rogers, John A

    2014-01-01

    The ability to measure subtle changes in arterial pressure using devices mounted on the skin can be valuable for monitoring vital signs in emergency care, detecting the early onset of cardiovascular disease and continuously assessing health status. Conventional technologies are well suited for use in traditional clinical settings, but cannot be easily adapted for sustained use during daily activities. Here we introduce a conformal device that avoids these limitations. Ultrathin inorganic piezoelectric and semiconductor materials on elastomer substrates enable amplified, low hysteresis measurements of pressure on the skin, with high levels of sensitivity (~0.005 Pa) and fast response times (~0.1 ms). Experimental and theoretical studies reveal enhanced piezoelectric responses in lead zirconate titanate that follow from integration on soft supports as well as engineering behaviours of the associated devices. Calibrated measurements of pressure variations of blood flow in near-surface arteries demonstrate capabilities for measuring radial artery augmentation index and pulse pressure velocity. PMID:25092496

  6. Crystal structure and electrical properties of bismuth sodium titanate zirconate ceramics

    PubMed Central

    2012-01-01

    Lead-free bismuth sodium titanate zirconate (Bi0.5Na0.5Ti1-xZrxO3 where x = 0.20, 0.35, 0.40, 0.45, 0.60, and 0.80 mole fraction) [BNTZ] ceramics were successfully prepared using the conventional mixed-oxide method. The samples were sintered for 2 h at temperatures lower than 1,000°C. The density of the BNTZ samples was at least 95% of the theoretical values. The scanning electron microscopy micrographs showed that small grains were embedded between large grains, causing a relatively wide grain size distribution. The density and grain size increased with increasing Zr concentration. A peak shift in X-ray diffraction patterns as well as the disappearance of several hkl reflections indicated some significant crystal-structure changes in these materials. Preliminary crystal-structure analysis indicated the existence of phase transition from a rhombohedral to an orthorhombic structure. The dielectric and ferroelectric properties were also found to correlate well with the observed phase transition. PMID:22221595

  7. Microstrain in tetragonal lead-zirconate-titanate: The effect of pressure on the ionic displacements

    SciTech Connect

    Frantti, J. Fujioka, Y.; Zhang, J.; Zhu, J.; Vogel, S. C.; Zhao, Y.

    2014-08-15

    Piezoelectric materials respond to external stimuli by adjusting atomic positions. In solid-solutions, the changes occurring in atomic scale are very complex since the short- and long-range order are different. Standard methods used in diffraction data analysis fail to model the short-range order accurately. Pressure-induced cation displacements in ferroelectric Pb(Zr{sub 0.45}Ti{sub 0.55})O{sub 3} perovskite oxide are modeled by starting from a short-range order. We show that the model gives the average structure correctly and properly describes the local structure. The origin of the microstrain in lead zirconate titanate is the spatially varying Zr and Ti concentration and atomic distances, which is taken into account in the simulation. High-pressure neutron powder diffraction and simulation techniques are applied for the determination of atomic positions and bond-valences as a function of pressure. Under hydrostatic pressure, the material loses its piezoelectric properties far before the transition to the cubic phase takes place. The total cation valence +6 is preserved up to 3.31 GPa by compensating the increasing B-cation valence by decreasing Pb-displacement from the high-symmetry position. At 3.31 GPa, Pb-displacement is zero and the material is no more ferroelectric. This is also the pressure at which the Pb-valence is minimized. The average structure is still tetragonal. The model for microstrain predicts that the transition occurs over a finite pressure range: Pb-displacements are spatially varying and follow the distribution of Zr and Ti ions.

  8. Thermally induced modifications of the optic properties of lead zirconate titanate thin films obtained on different substrates by sol-gel synthesis

    SciTech Connect

    D'Elia, Stefano; Castriota, Marco; Scaramuzza, Nicola; Versace, Carlo; Cazzanelli, Enzo; Vena, Carlo; Strangi, Giuseppe; Bartolino, Roberto; Policicchio, Alfonso; Agostino, Raffaele Giuseppe

    2008-12-15

    Lead zirconium titanate PbZr{sub 0.53}Ti{sub 0.47}O{sub 3} (PZT) thin films have been obtained by sol-gel synthesis, deposited on different substrates [float glass, indium tin oxide (ITO)-coated float glass, and intrinsic silicon wafer], and later subjected to different thermal treatments. The morphologic and the structural properties of both PZT thin films and substrates have been investigated by scanning electron microscope and their composition was determined by energy dispersive x-ray (EDX) analysis. Moreover, variable angle spectroscopic ellipsometry provides relevant information on the electronic and optical properties of the samples. In particular, the optical constant dispersion of PZT deposited on ITO-coated float glasses shows a small absorption resonance in the near IR region, not observed in PZT films deposited on the other substrates, so that such absorption resonance can be explained by interfacial effects between ITO and PZT layers. This hypothesis is also supported by EDX measurements, showing an interdiffusion of lead and indium ions, across the PZT-ITO interface, that can generate a peculiar charge distribution in this region.

  9. Piezoelectric Energy Harvesting Using PZT Bimorphs and Multilayered Stacks

    NASA Astrophysics Data System (ADS)

    Panda, Prasanta Kumar; Sahoo, Benudhar; Chandraiah, M.; Raghavan, Sreekumari; Manoj, Bindu; Ramakrishna, J.; Kiran, P.

    2015-11-01

    Piezoelectric materials have a unique ability to interchange electrical and mechanical energy. This property allows the absorption of mechanical energy such as ambient vibration and its transformation into electrical energy. The electrical energy generated can be used to power low-power electronic devices. In the present study, energy harvesting by lead zirconate titanate (PZT) multilayer (ML) stacks and bimorphs is presented. The devices were fabricated by a tape casting technique and were poled at 2 kV/mm for 30 min immersed in a silicone oil bath maintained at 60°C. The energy harvesting characteristics of the fabricated devices were measured in a suitably assembled test setup. The output voltage obtained from the PZT bimorphs and ML stacks was 450 mV and 125 mV, respectively. The higher output voltage from the bimorph is due to its low capacitance.

  10. From lab to industrial: PZT nanoparticles synthesis and process control for application in additive manufacturing

    NASA Astrophysics Data System (ADS)

    Huang, Hsien-Lin

    Lead Zirconate Titanate (PZT) nanoparticles hold many promising current and future applications, such as PZT ink for 3-D printing or seeds for PZT thick films. One common method is hydrothermal growth, in which temperature, duration time, or mineralizer concentrations are optimized to produce PZT nanoparticles with desired morphology, controlled size and size distribution. A modified hydrothermal process is used to fabricate PZT nanoparticles. The novelty is to employ a high ramping rate (e.g., 20 deg C/min) to generate abrupt supersaturation so as to promote burst nucleation of PZT nanoparticles as well as a fast cooling rate (e.g., 5 deg C/min) with a controlled termination of crystal growth. As a result, PZT nanoparticles with a size distribution ranging from 200 nm to 800 nm are obtained with cubic morphology and good crystallinity. The identification of nanoparticles is confirmed through use of X-ray diffractometer (XRD). XRD patterns are used to compare sample variations in their microstructures such as lattice parameter. A cubic morphology and particle size are also examined via SEM images. The hydrothermal process is further modified with excess lead (from 20% wt. to 80% wt.) to significantly reduce amorphous phase and agglomeration of the PZT nanoparticles. With a modified process, the particle size still remains within the 200 nm to 800 nm. Also, the crystal structures (microstructure) of the samples show little variations. Finally, a semi-continuous hydrothermal manufacturing process was developed to substantially reduce the fabrication time and maintained the same high quality as the nanoparticles prepared in an earlier stage. In this semi-continuous process, a furnace is maintained at the process temperature (200 deg C), whereas autoclaves containing PZT sol are placed in and out of the furnace to control the ramp-up and cooling rates. This setup eliminates an extremely time-consuming step of cooling down the furnace, thus saving tremendous amount of

  11. Deformation behavior of lead zirconate titanate ceramics under uniaxial compression measured by the digital image correlation method

    NASA Astrophysics Data System (ADS)

    Chen, Di; Carter, Emma; Kamlah, Marc

    2016-09-01

    The deformation behavior of lead zirconate titanate bulk ceramic specimen under uniaxial compression was monitored by the digital image correlation method and the homogeneity of the deformation was discussed. Combined with using a Sawyer–Tower circuit, the depolarization curve was also obtained. Because of the friction at both the top and bottom surfaces of the lead zirconate titanate ceramic specimen, the distribution of deformation under large uniaxial compressive stresses usually shows a barrel shape. By focusing on correspondingly selected regions of interest and calculating the values of strain components there, the barreling behavior was proved. This barreling behavior is due to elastic strains, in the first place, while the remnant strains are less affected by this phenomenon. All these findings are the experimental justifications for the selection of an aspect ratio of 3:1 for our specimens, where only the central cubic region of a specimen represents the desired purely uniaxial stress state. Only from this region, true uniaxial stress–strain results can be obtained to develop constitutive models.

  12. Titan

    NASA Technical Reports Server (NTRS)

    Owen, Tobias; Gautier, Daniel; Raulin, Francois; Scattergood, Thomas

    1992-01-01

    The following topics are discussed with respect to Titan: observations of the atmosphere; laboratory simulations and theoretical models of Titan's atmosphere; endpoints of atmospheric chemistry - aerosols and oceans; exobiology; and the next steps in understanding Titan.

  13. Temperature Dependent Mechanical Property of PZT Film: An Investigation by Nanoindentation

    PubMed Central

    Li, Yingwei; Feng, Shangming; Wu, Wenping; Li, Faxin

    2015-01-01

    Load-depth curves of an unpoled Lead Zirconate Titanate (PZT) film composite as a function of temperature were measured by nanoindentation technique. Its reduce modulus and hardness were calculated by the typical Oliver-Pharr method. Then the true modulus and hardness of the PZT film were assessed by decoupling the influence of substrate using methods proposed by Zhou et al. and Korsunsky et al., respectively. Results show that the indentation depth and modulus increase, but the hardness decreases at elevated temperature. The increasing of indentation depth and the decreasing of hardness are thought to be caused by the decreasing of the critical stress needed to excite dislocation initiation at high temperature. The increasing of true modulus is attributed to the reducing of recoverable indentation depth induced by back-switched domains. The influence of residual stress on the indentation behavior of PZT film composite was also investigated by measuring its load-depth curves with pre-load strains. PMID:25768957

  14. Enhanced ferroelectric and piezoelectric properties in La-modified PZT ceramics

    NASA Astrophysics Data System (ADS)

    Kour, P.; Pradhan, S. K.; Kumar, Pawan; Sinha, S. K.; Kar, Manoranjan

    2016-06-01

    The effect of lanthanum (La) doping on ferroelectric and piezoelectric properties of lead zirconate titanate (PZT) sample has been investigated. Pb1- x La x Zr0.52Ti0.48O3 ceramics with x = 0.00, 0.02, 0.04, 0.06 and 0.10 were prepared by the sol-gel technique. Raman and Fourier transforms infrared spectroscopy have been employed to understand the structural modification due to ionic size mismatch. Raman spectra show the existence of both rhombohedral and tetragonal crystal symmetries. It also shows the dielectric relaxation with increase in La concentration in the sample. The increase in lattice strain due to La doping increases the remnant polarization and coercive field. The linear piezoelectric coefficient increases with the increase in La concentration. It reveals that La-substituted PZT is a better candidate for piezoelectric sensor applications as compared to that of PZT.

  15. Temperature dependent mechanical property of PZT film: an investigation by nanoindentation.

    PubMed

    Li, Yingwei; Feng, Shangming; Wu, Wenping; Li, Faxin

    2015-01-01

    Load-depth curves of an unpoled Lead Zirconate Titanate (PZT) film composite as a function of temperature were measured by nanoindentation technique. Its reduce modulus and hardness were calculated by the typical Oliver-Pharr method. Then the true modulus and hardness of the PZT film were assessed by decoupling the influence of substrate using methods proposed by Zhou et al. and Korsunsky et al., respectively. Results show that the indentation depth and modulus increase, but the hardness decreases at elevated temperature. The increasing of indentation depth and the decreasing of hardness are thought to be caused by the decreasing of the critical stress needed to excite dislocation initiation at high temperature. The increasing of true modulus is attributed to the reducing of recoverable indentation depth induced by back-switched domains. The influence of residual stress on the indentation behavior of PZT film composite was also investigated by measuring its load-depth curves with pre-load strains. PMID:25768957

  16. Electrochemistry of ferroelectric thin film lead zirconate titanate in sulfuric acid

    NASA Astrophysics Data System (ADS)

    Small, Leo J.

    Remote sensing applications in harsh environments require sensor materials appropriately matched to the environment. PbZr0.52Ti0.48O 3 (PZT) is a candidate for remote sensing applications, where it could be used as both a sensor and power source. In this light, the evolution of the PZT-H2SO4 interface is explored at low pHs. A robotic microdroplet cell is developed to differentiate the electrochemical response of the cracks and pores inherent to the PZT film from that of continuous PZT. Accelerated chemical attack is observed at the pores, while the continuous PZT displays electrochemical hysteresis; the ferroelectric-solution interface can be switched between two different charge states at a given potential. As time progresses, electrochemical impedance spectroscopy reveals a change in the structure of the PZT-H2SO4 interface. Development of equivalent circuits to model the competing processes of pore growth, interfacial layer formation, and uniform chemical attack are guided by the evolution of film structure and chemistry as observed ex-situ with scanning electron microscopy, x-ray photoelectron spectroscopy, and x-ray diffraction. The Point Defect Model for the passive state is used to explain the dissolution processes observed in the complex oxide. Application of this model to PbZrxTi1- xO3 for x = 0.25, 0.52, and 0.95 points to the role of titanium in the creation of an ionically insulating layer that impedes further chemical attack.

  17. Domain pinning near a single-grain boundary in tetragonal and rhombohedral lead zirconate titanate films

    DOE PAGESBeta

    Marincel, Dan M.; Zhang, H. R.; Briston, J.; Belianinov, Alex; Jesse, Stephen; Kalinin, Sergei V.; Chen, L. Q.; Rainforth, William M.; Reaney, Ian M.; Randall, Clive A.; et al

    2015-04-27

    The interaction of grain boundaries with ferroelectric domain walls strongly influences the extrinsic contribution to piezoelectric activity in Pb(Zr,Ti)O3 (PZT), ubiquitous in modern transducers and actuators. However, the fundamental understanding of these phenomena has been limited by complex mechanisms originating from the interplay of atomic-level domain wall pinning, collective domain wall dynamics, and emergent mesoscopic behavior. This contribution utilizes engineered grain boundaries created by depositing epitaxial PZT films with various Zr:Ti ratio onto 24º SrTiO3 tilt bicrystals. The nonlinear piezoelectric response and surface domain structure across the boundary are investigated using piezoresponse force microscopy whilst cross section domain structure ismore » studied using transmission electron microscopy. The grain boundary reduces domain wall motion over a width of 800±70 nm for PZT 45:55 and 450±30 nm for PZT 52:48. Phase field modeling provides an understanding of the elastic and electric fields associated with the grain boundary and local domain configurations. In conclusion, this study demonstrates that complex mesoscopic behaviors can be explored to complement atomic-level pictures of the material system.« less

  18. Domain pinning near a single-grain boundary in tetragonal and rhombohedral lead zirconate titanate films

    SciTech Connect

    Marincel, Dan M.; Zhang, H. R.; Briston, J.; Belianinov, Alex; Jesse, Stephen; Kalinin, Sergei V.; Chen, L. Q.; Rainforth, William M.; Reaney, Ian M.; Randall, Clive A.; Trolier-McKinstry, Susan

    2015-04-27

    The interaction of grain boundaries with ferroelectric domain walls strongly influences the extrinsic contribution to piezoelectric activity in Pb(Zr,Ti)O3 (PZT), ubiquitous in modern transducers and actuators. However, the fundamental understanding of these phenomena has been limited by complex mechanisms originating from the interplay of atomic-level domain wall pinning, collective domain wall dynamics, and emergent mesoscopic behavior. This contribution utilizes engineered grain boundaries created by depositing epitaxial PZT films with various Zr:Ti ratio onto 24º SrTiO3 tilt bicrystals. The nonlinear piezoelectric response and surface domain structure across the boundary are investigated using piezoresponse force microscopy whilst cross section domain structure is studied using transmission electron microscopy. The grain boundary reduces domain wall motion over a width of 800±70 nm for PZT 45:55 and 450±30 nm for PZT 52:48. Phase field modeling provides an understanding of the elastic and electric fields associated with the grain boundary and local domain configurations. In conclusion, this study demonstrates that complex mesoscopic behaviors can be explored to complement atomic-level pictures of the material system.

  19. Study of PZT thick-film infrared detectors prepared by MEMS technology

    NASA Astrophysics Data System (ADS)

    Qiang, Xiang-Peng; Chuan, Gui-Wu; Wen, Bo-Luo; Wan, Li-Zhang; Jia, Qiang-Cao

    2011-08-01

    In this paper, a single element integrated infrared detector using screen printed lead zirconate titanate (PZT) thick films on Pt/Ti/Al2O3/SiO2 coated silicon cup has been developed. The thermal insulating micro-bridge of the detector was prepared by Micro-electro-mechanical System (MEMS) technology. To increase the density of PZT ceramic thick films, cool isostatic pressing experiments had been conducted under 300MPa and 30s dwell time. The XRD pattern shows that PZT thick films possess good perovskite structure. The SEM cross section image demonstrate that the PZT film was dense and the thickness is about 25μm. The dielectric constant, loss and pyroelectric coefficient of PZT thick films prepared at optimized conditions is 1100, 1% and 1×10-8C/Kcm 2, respectively. The results indicated that the PZT thermal sensitive layer fabricated by screen printing on the Pt/Ti coated silicon cup with micro-bridge thermal insulation structure, and Al2O3/SiO2 barrier layer show potential application in infrared detectors.

  20. Deformation in lead zirconate titanate ceramics under large signal electric field loading measured by digital image correlation

    NASA Astrophysics Data System (ADS)

    Chen, Di; Kamlah, Marc

    2015-11-01

    Digital image correlation, a noncontact and nondestructive method, was employed to monitor the deformation of lead zirconate titanate piezoelectric ceramics. This method is based on imaging a speckle pattern on the specimen surface during the test and subsequently correlating each image of the deformed pattern to that in the reference state. In our work, both longitudinal and transverse strains were calculated from imaging a bulk sample under a ±2 kV/mm electric field. Compared with linear variable displacement transducer data, the results from this correlation method were validated. At the same time, based on this optical technique, different strain-electric field butterfly loops can be drawn from correspondingly selected regions of interest. Combined with contour plots of strain on the surface of the sample, the deformation of bulk ceramic sample under uniaxial electric field loading without any mechanical constraints is proven to be highly homogenous under macro-observing scale.

  1. Thickness effect on the structure, grain size, and local piezoresponse of self-polarized lead lanthanum zirconate titanate thin films

    NASA Astrophysics Data System (ADS)

    Melo, M.; Araújo, E. B.; Shvartsman, V. V.; Shur, V. Ya.; Kholkin, A. L.

    2016-08-01

    Polycrystalline lanthanum lead zirconate titanate (PLZT) thin films were deposited on Pt/TiO2/SiO2/Si substrates to study the effects of the thickness and grain size on their structural and piezoresponse properties at nanoscale. Thinner PLZT films show a slight (100)-orientation tendency that tends to random orientation for the thicker film, while microstrain and crystallite size increases almost linearly with increasing thickness. Piezoresponse force microscopy and autocorrelation function technique were used to demonstrate the existence of local self-polarization effect and to study the thickness dependence of correlation length. The obtained results ruled out the bulk mechanisms and suggest that Schottky barriers near the film-substrate are likely responsible for a build-in electric field in the films. Larger correlation length evidence that this build-in field increases the number of coexisting polarization directions in larger grains leading to an alignment of macrodomains in thinner films.

  2. Design of a dual-effect lens on lanthanum-modified lead zirconate titanate for continuous variation of focal length

    NASA Astrophysics Data System (ADS)

    Castro, Francisco; Nabet, Bahram

    1995-05-01

    The design of a Fresnel lens with continuous focal length is proposed for use in optical processing. A convex lens is induced in lanthanum-modified lead zirconate titanate through the application of an electric-field profile supplied by the indium tin oxide electrodes that make up the zones of a Fresnel lens. The use of a numerical method based on fast Fourier transform algorithms was required to analyze accurately the induced field inside a Fresnel lens with an initial focal length of 0.4 m (at 470 nm) and 20 indium tin oxide electrodes. The effective focal location obtained by the combined mechanisms is derived. This design is expected to produce continuous variations of approximately 16% in focal length; the ability of previous designs to achieve focal length switching is maintained.

  3. Modified Johnson model for ferroelectric lead lanthanum zirconate titanate at very high fields and below Curie temperature.

    SciTech Connect

    Narayanan, M.; Tong, S.; Ma, B.; Liu, S.; Balachandran, U.

    2012-01-01

    A modified Johnson model is proposed to describe the nonlinear field dependence of the dielectric constant ({var_epsilon}-E loop) in ferroelectric materials below the Curie temperature. This model describes the characteristic ferroelectric 'butterfly' shape observed in typical {var_epsilon}-E loops. The predicted nonlinear behavior agreed well with the measured values in both the low- and high-field regions for lead lanthanum zirconate titanate films. The proposed model was also validated at different temperatures below the ferroelectric-to-paraelectric Curie point. The anharmonic coefficient in the model decreased from 6.142 x 10{sup -19} cm{sup 2}/V{sup 2} to 2.039 x 10{sup -19} cm{sup 2}/V{sup 2} when the temperature increased from 25 C to 250 C.

  4. Dielectric properties of lead lanthanum zirconate titanate thin films with and without ZrO2 insertion layers

    NASA Astrophysics Data System (ADS)

    Liu, Shanshan; Ma, Beihai; Narayanan, Manoj; Tong, Sheng; Koritala, Rachel E.; Hu, Zhongqiang; Balachandran, Uthamalingam

    2013-05-01

    The dielectric properties of lead lanthanum zirconate titanate (PLZT) thin films on platinized silicon (Pt/Si) with and without ZrO2 insertion layers were investigated in the temperature range from 20 °C to 300 °C. Permittivity, dielectric loss tangent, and tunability were reduced for the samples with ZrO2 insertion layers compared to those without the layers. Additionally, the permittivity was less dependent on frequency over the broad temperature range studied (20-300 °C). The leakage current behavior of the PLZT films with and without ZrO2 insertion layers was also investigated, and on the basis of those results, a probable conduction mechanism has been suggested. The improved electrical properties in the PLZT with ZrO2 layers are attributed to the ZrO2 layer blocking the mobile ionic defects and reducing free charge carriers to transport.

  5. Stress-optic modulator in TriPleX platform using a ezoelectric lead zirconate titanate (PZT) thin film.

    PubMed

    Hosseini, Naser; Dekker, Ronald; Hoekman, Marcel; Dekkers, Matthijn; Bos, Jan; Leinse, Arne; Heideman, Rene

    2015-06-01

    We will demonstrate a stress-optic phase modulator in the passive SiN-based TriPleX platform using a layer of piezoelectric material. Regarding the stress-optic effect, the piezoelectric layer deposited on top of an optical waveguide is employed to control the phase of propagating light in the structure by applying an electrical field across the layer. In this work, it is demonstrated that the stress-optic effect lowers the power consumption by a factor of one million for quasi-DC operation and increases the modulation speed by three orders of magnitude, compared to currently used thermo-optic modulation in the TriPleX platform. PMID:26072771

  6. Polar-axis-oriented crystal growth of tetragonal PZT films on stainless steel substrate using pseudo-perovskite nanosheet buffer layer

    NASA Astrophysics Data System (ADS)

    Minemura, Yoshiki; Ichinose, Daichi; Nagasaka, Kohei; Kim, Jin Woon; Shima, Hiromi; Nishida, Ken; Kiguchi, Takanori; Konno, Toyohiko J.; Oshima, Naoya; Funakubo, Hiroshi; Uchida, Hiroshi

    2015-07-01

    Lead zirconate titanate (PZT) film with polar axis orientation was grown on a SUS 316L stainless steel substrate with the help of a Ca2Nb3O10 nanosheet (ns-CN) layer that had a pseudo-perovskite-type crystal structure. The ns-CN buffer layer was supported on a platinized SUS 316L (Pt/SUS) substrate, followed by chemical solution deposition (CSD) of the PZT films with tetragonal symmetry (Zr/Ti =40/60). The PZT films consisting of c-domain, with [001]-axis orientation of the perovskite unit cell, were deposited on the ns-CN/Pt/SUS substrate owing to (i) epitaxial lattice matching between the unit cell of PZT and substrate surface and (ii) in-plane thermal stress applied to the PZT film during cooling-down step of CSD procedure. The c-domain-oriented PZT film on ns-CN/Pt/SUS substrate exhibited enhanced remanent polarization of approximately 52 μC/cm2 and lowered dielectric permittivity of approximately 230, which are superior to those of conventional PZT films with random crystal orientation and comparable to those of epitaxial PZT films grown on (100)SrRuO3//(100)SrTiO3 substrates.

  7. PZT Thin Film Piezoelectric Traveling Wave Motor

    NASA Technical Reports Server (NTRS)

    Shen, Dexin; Zhang, Baoan; Yang, Genqing; Jiao, Jiwei; Lu, Jianguo; Wang, Weiyuan

    1995-01-01

    With the development of micro-electro-mechanical systems (MEMS), its various applications are attracting more and more attention. Among MEMS, micro motors, electrostatic and electromagnetic, are the typical and important ones. As an alternative approach, the piezoelectric traveling wave micro motor, based on thin film material and integrated circuit technologies, circumvents many of the drawbacks of the above mentioned two types of motors and displays distinct advantages. In this paper we report on a lead-zirconate-titanate (PZT) piezoelectric thin film traveling wave motor. The PZT film with a thickness of 150 micrometers and a diameter of 8 mm was first deposited onto a metal substrate as the stator material. Then, eight sections were patterned to form the stator electrodes. The rotor had an 8 kHz frequency power supply. The rotation speed of the motor is 100 rpm. The relationship of the friction between the stator and the rotor and the structure of the rotor on rotation were also studied.

  8. Study of global and local crystallography at the domain boundaries of lead zirconate titanate piezoelectric ceramics

    NASA Astrophysics Data System (ADS)

    Farooq, M. U.; Villaurrutia, R.; MacLaren, I.; Kungl, H.; Hoffmann, M. J.; Fundenberger, J.-J.; Bouzy, E.

    2008-08-01

    Reliable automated orientation mapping of 90° domains in a tetragonal perovskite has been achieved for the first time using both EBSD and TEM-Kikuchi pattern analysis. This has been used to compare local measurements of c/a ratios in PZT with global measurements by X-ray diffraction. The local c/a rations are in broad agreement with the global measurements, but further work is needed to determine whether the small discrepancies are real local variations or are caused by experimental factors.

  9. Sensitivity of PZT Impedance Sensors for Damage Detection of Concrete Structures

    PubMed Central

    Yang, Yaowen; Hu, Yuhang; Lu, Yong

    2008-01-01

    Piezoelectric ceramic Lead Zirconate Titanate (PZT) based electro-mechanical impedance (EMI) technique for structural health monitoring (SHM) has been successfully applied to various engineering systems. However, fundamental research work on the sensitivity of the PZT impedance sensors for damage detection is still in need. In the traditional EMI method, the PZT electro-mechanical (EM) admittance (inverse of the impedance) is used as damage indicator, which is difficult to specify the effect of damage on structural properties. This paper uses the structural mechanical impedance (SMI) extracted from the PZT EM admittance signature as the damage indicator. A comparison study on the sensitivity of the EM admittance and the structural mechanical impedance to the damages in a concrete structure is conducted. Results show that the SMI is more sensitive to the damage than the EM admittance thus a better indicator for damage detection. Furthermore, this paper proposes a dynamic system consisting of a number of single-degree-of-freedom elements with mass, spring and damper components to model the SMI. A genetic algorithm is employed to search for the optimal value of the unknown parameters in the dynamic system. An experiment is carried out on a two-storey concrete frame subjected to base vibrations that simulate earthquake. A number of PZT sensors are regularly arrayed and bonded to the frame structure to acquire PZT EM admittance signatures. The relationship between the damage index and the distance of the PZT sensor from the damage is studied. Consequently, the sensitivity of the PZT sensors is discussed and their sensing region in concrete is derived.

  10. Physical vapor deposition of multilayered lead-zirconate-titanate films for ultrasonic transducer fabrication

    NASA Astrophysics Data System (ADS)

    Kline-Schoder, Robert J.; Kynor, David B.; Jaeger, Michael D.; Winder, Alan A.; Desilets, Charles S.

    1999-06-01

    Creare is developing microfabrication techniques to manufacture low-cost, multi-dimensional ultrasonic transducer arrays with single- and multi-layer piezoelectric elements for low impedance and high sensitivity. The manufacturing approach is scaleable for fabrication of transducer arrays in the frequency range of 10 - 50 MHz in dense or sparse array configurations. Our approach employs the following processes: (1) Physical Vapor Deposition (PVD or sputtering) of high-quality, piezoelectric films using reactive sputtering of metallic targets and (2) Novel use of state-of-the-art photolithography and masking to provide the interlayer electrodes, element interconnections, and array element fabrication. To date, Creare has successfully demonstrated that piezoelectrically active thick films of PZT material can be deposited by using a reactive sputtering approach. In addition, these thick, multi-layer PZT films have been formed into high aspect ratio elements using dicing to fabricate a 12 MHz transducer. Array designs based on these films show that expected performance should meet the requirements for high resolution biomedical imaging.

  11. Influence of crystal phase and transparent substrates on electro-optic properties of lead zirconate titanate films

    SciTech Connect

    Zhu, M. M.; Du, Z. H.; Ma, J.

    2010-12-01

    Pb(Zr{sub x}Ti{sub 1-x})O{sub 3}[x=0.52, PZT(52) near morphotropic phase boundary], tetragonal PZT(65), and rhombohedral PZT(20) thin films have been fabricated on different transparent substrates by radio frequency sputtering. The optical studies show that the band gap energies and refractive indices of the PZT thin films are crystal phase dependent. The largest electro-optic (EO) coefficient of 219.6 pm/V has been achieved by controlling the crystal phase of the PZT thin films. The linear EO coefficients of PZT(52) films on the (Pb{sub 0.86}La{sub 0.14})TiO{sub 3}-coated glass, indium tin oxides, and MgO substrates are also studied. Such study could contribute to the crystal phase and substrate dependent PZT films for electro-optic devices and multifunctional integrated circuits.

  12. Titan

    NASA Astrophysics Data System (ADS)

    Coustenis, Athena

    Titan, Saturn's biggest satellite (second in size among the satellites in our solar system), has attracted the eye of astronomers preferentially ever since its discovery by Dutch astronomer Christiaan Huygens on March 25, 1655. Titan orbits around Saturn at a distance of 1,222,000 km (759,478 mi) in a synchronous rotation, taking 15.9 days to complete. As Titan follows Saturn on its trek around the Sun, one Titanian year equals about 30 Earth years. The sunlight that reaches such distances is only 1/100th of that received by the Earth. Titan is therefore a cold and dark place, but a fascinating one.

  13. Application of Multiplexed FBG and PZT Impedance Sensors for Health Monitoring of Rocks

    PubMed Central

    Yang, Yaowen; Annamdas, Venu Gopal Madhav; Wang, Chao; Zhou, Yingxin

    2008-01-01

    Reliable structural health monitoring (SHM) including nondestructive evaluation (NDE) is essential for safe operation of infrastructure systems. Effective monitoring of the rock components of civil infrastructures such as tunnels and caverns remains challenging. The feasibility of employing smart optical fibre sensor (OFS) and piezoelectric impedance sensor made up of lead zirconate titanate (PZT) for comprehensive health monitoring of rocks, covering load history monitoring/retrieval as well as damage assessment is presented in this paper. The rock specimens are subjected to cyclic loading and their conditions are continuously monitored using OFS and PZT sensors. OFS based multiplexed fibre Bragg grating (FBG) sensors are surface bonded on the rock specimens. Their strain sensing performance is compared with the conventional electric strain gauges (ESGs). In addition, PZT patches are also bonded on the specimens to study the damage pattern during different loading cycles. Unlike the FBGs or ESGs, PZT patches are used as bi-functional sensors and actuators, enabling them to be efficient detectors of incipient damages using the principle of electromechanical impedance. The experimental study demonstrated superior performance of these smart FBG and PZT impedance sensors. This work is expected to be useful for SHM based NDE application of rock structures such as caverns and tunnels.

  14. Titan

    NASA Astrophysics Data System (ADS)

    Müller-Wodarg, Ingo; Griffith, Caitlin A.; Lellouch, Emmanuel; Cravens, Thomas E.

    2014-03-01

    Introduction I. C. F. Müller-Wodarg, C. A. Griffith, E. Lellouch and T. E. Cravens; Prologue 1: the genesis of Cassini-Huygens W.-H. Ip, T. Owen and D. Gautier; Prologue 2: building a space flight instrument: a P.I.'s perspective M. Tomasko; 1. The origin and evolution of Titan G. Tobie, J. I. Lunine, J. Monteux, O. Mousis and F. Nimmo; 2. Titan's surface geology O. Aharonson, A. G. Hayes, P. O. Hayne, R. M. Lopes, A. Lucas and J. T. Perron; 3. Thermal structure of Titan's troposphere and middle atmosphere F. M. Flasar, R. K. Achterberg and P. J. Schinder; 4. The general circulation of Titan's lower and middle atmosphere S. Lebonnois, F. M. Flasar, T. Tokano and C. E. Newman; 5. The composition of Titan's atmosphere B. Bézard, R. V. Yelle and C. A. Nixon; 6. Storms, clouds, and weather C. A. Griffith, S. Rafkin, P. Rannou and C. P. McKay; 7. Chemistry of Titan's atmosphere V. Vuitton, O. Dutuit, M. A. Smith and N. Balucani; 8. Titan's haze R. West, P. Lavvas, C. Anderson and H. Imanaka; 9. Titan's upper atmosphere: thermal structure, dynamics, and energetics R. V. Yelle and I. C. F. Müller-Wodarg; 10. Titan's upper atmosphere/exosphere, escape processes, and rates D. F. Strobel and J. Cui; 11. Titan's ionosphere M. Galand, A. J. Coates, T. E. Cravens and J.-E. Wahlund; 12. Titan's magnetospheric and plasma environment J.-E. Wahlund, R. Modolo, C. Bertucci and A. J. Coates.

  15. The Effects of TI/PT Bottom Electrode on Crystallographic and Surface Characteristics of PZT Thick Films

    NASA Astrophysics Data System (ADS)

    Koochekzadeh, Ali; Keshavarz Alamdari, Eskandar; Barzegar, Abdolghafar

    The ceramic lead zirconate titanate (PZT) films near the morphotropic phase boundary are successfully integrated into MEMS devices, especially for applications in microsensors and actuators. The ferro/piezo electric properties of PZT thick films are widely dependent on its surface quality and crystallographic orientation growth. This paper indicates the influences of platinum bottom electrode on the surface and crystallographic properties of PZT. Ti (10nm) and Pt (100nm) thin films have been deposited on silicon substrate by thermal evaporation and electron beam respectively without vacuum breaking. After annealing treatment, the Pt film exhibited (111) preferred orientation. Finally one micron thick PZT (54/46) film was deposited by a RF magnetron sputtering at room temperature in pure Argon followed by a conventional post annealing treatment on silicon substrate. The XRD measurements have shown the provskite structure of PZT films with (100) preferred orientation at annealing temperatures above 600°C and (111) preferred orientation above 650°c. The SEM results demonstrate that whatever the annealing temperature is increased, recrystallization grains and black holes on Pt surface occurs and cause morphological change of PZT surface. The AFM test shows the strong RMS roughness of platinum surface after annealing temperature at 650°C.

  16. Residual stress relief due to fatigue in tetragonal lead zirconate titanate ceramics

    SciTech Connect

    Hall, D. A.; Mori, T.; Comyn, T. P.; Ringgaard, E.; Wright, J. P.

    2013-07-14

    High energy synchrotron XRD was employed to determine the lattice strain {epsilon}{l_brace}111{r_brace}and diffraction peak intensity ratio R{l_brace}200{r_brace}in tetragonal PZT ceramics, both in the virgin poled state and after a bipolar fatigue experiment. It was shown that the occurrence of microstructural damage during fatigue was accompanied by a reduction in the gradient of the {epsilon}{l_brace}111{r_brace}-cos{sup 2} {psi} plot, indicating a reduction in the level of residual stress due to poling. In contrast, the fraction of oriented 90 Degree-Sign ferroelectric domains, quantified in terms of R{l_brace}200{r_brace}, was not affected significantly by fatigue. The change in residual stress due to fatigue is interpreted in terms of a change in the average elastic stiffness of the polycrystalline matrix due to the presence of inter-granular microcracks.

  17. Phase field simulation of domain switching dynamics in multiaxial lead zirconate titanate thin films

    NASA Astrophysics Data System (ADS)

    Britson, Jason

    The defining characteristic of ferroelectric materials is their ability to be switched between energetically equivalent polarization states. This behavior has led to an interest in ferroelectrics for a wide range of bulk and thin film applications such as mechanical actuators and ferroelectric random access memory devices. Ferroelectric switching depends on domain wall motion, however, and is critically influenced by the existence of defects such as dislocations and preexisting domains. Domain wall motion in thin film applications can be controlled by individual local defects due to the reduced length scale of the system. This dissertation describes the impact of preexisting ferroelastic domains and misfits dislocations in coherent (001)-oriented Pb(Zr0.2,Ti0.8)O3 (PZT) thin films on the switching response and domain structure. A phase field model based on the Landau-Ginzburg-Devonshire theory that accounts for the electrostatic and mechanical interactions is used to describe domain structures in ferroelectric PZT thin films. To solve the governing equations a semi-implicit Fourier-Spectral scheme is developed that accommodates boundary conditions appropriate to the thin film geometry. Errors are reduced in the solutions at the film edges through extensions to the model developed to correct the Fourier transform around stationary discontinuities at the thin film edges. This correction is shown to result in increased accuracy of the phase field model needed to appropriately describe dynamic switching responses in the thin film. Investigation of switching around preexisting ferroelastic domains showed these defects are strong obstacles to switching in PZT thin films. Directly above the ferroelastic domain the magnitude of the required nucleation bias underneath a tip-like electrode was found to be elevated compared to the required bias far from the domain. Locally both the piezoelectric and dielectric responses of the thin film were found to be suppressed, which is

  18. The structure and dielectric properties of thin barium zirconate titanate films obtained by RF magnetron sputtering

    NASA Astrophysics Data System (ADS)

    Tumarkin, A. V.; Razumov, S. V.; Gagarin, A. G.; Altynnikov, A. G.; Stozharov, V. M.; Kaptelov, E. Yu.; Senkevich, S. V.; Pronin, I. P.

    2016-02-01

    Submicron thin layers of BaZr x Ti1- x O3 are grown in-situ by RF magnetron sputtering of a ceramic target ( x = 0.50) on a substrate of Pt/ r-cut leucosapphire Al2O3. It is shown that the composition of the ferroelectric layer is not identical to the composition of the sputtered target and is shifted toward barium zirconate. The reasons for such behavior are discussed. The obtained samples are characterized by high breakdown voltages (1 MV/cm and higher). The structural and high-frequency dielectric properties are studied, and high tunability of the capacitance of thin layers is revealed.

  19. Photosensitivity enhancement by H- and He-ion implantation in lead lanthanum zirconate titanate ceramics

    SciTech Connect

    Land, C.E.; Peercy, P.S.

    1980-07-01

    H- and He-ion implantation has been used to increase the photoferroelectric image storage sensitivity of lead lanthanum zirconium titanate ceramics by factors of approx.10 and approx.30, respectively. The increased photosensitivity can be attributed primarily to implantation-produced disorder, which increases the efficiency of carrier photoexcitation and trapping and reduces the exposure energy required to establish nonvolatile space-charge fields. Implantation-induced disorder may also contribute to a substantial increase in photoconductivity in the ion-damaged near-surface region.

  20. Resonant magnetoelectric coupling in trilayers of ferromagnetic alloys and piezoelectric lead zirconate titanate: The influence of bias magnetic field

    NASA Astrophysics Data System (ADS)

    Srinivasan, G.; de Vreugd, C. P.; Laletin, V. M.; Paddubnaya, N.; Bichurin, M. I.; Petrov, V. M.; Filippov, D. A.

    2005-05-01

    We present the first data and theory for the bias magnetic field dependence of magnetoelectric coupling in the electromechanical resonance (EMR) region for ferromagnetic-piezoelectric heterostructures. Trilayers of Permendur, a Co-Fe-V alloy, and lead zirconate titanate were studied. Measurements of the magnetoelectric (ME) voltage coefficient αE indicate a strong ME coupling in the low-frequency range and a giant ME effect due to EMR at 200-300kHz for radial modes and at ˜2.7MHz for thickness modes. Data were obtained for the bias field H dependence of two key parameters, the EMR frequency fr and the ME coefficient αE,R at resonance. With increasing H , an increase in fr and a rapid rise and fall in αE,R are measured. In our model we consider two mechanisms for the magnetic field influence on ME interactions: (i) a shift in the EMR frequency due to changes in compliance coefficients ( ΔE effect) and (ii) variation in the piezomagnetic coefficient that manifests as a change in αE,R . Theoretical profiles of αE vs frequency and estimates of frequency shift based on the ΔE effect are in excellent agreement with the data.

  1. Ferroelectric/Ferroelastic domain wall motion in dense and porous tetragonal lead zirconate titanate films.

    PubMed

    Johnson-Wilke, Raegan L; Wilke, Rudeger H T; Wallace, Margeaux; Rajashekhar, Adarsh; Esteves, Giovanni; Merritt, Zachary; Jones, Jacob L; Trolier-McKinstry, Susan

    2015-01-01

    Direct evidence of ferroelectric/ferroelastic domain reorientation is shown in Pb(Zr0.30Ti0.70)O3 (PZT30/70) thin films clamped to a rigid silicon substrate using in situ synchrotron X-ray diffraction during application of electric fields. Both dense films and films with 3 to 4 vol% porosity were measured. On application of electric fields exceeding the coercive field, it is shown that the porous films exhibit a greater volume fraction of ferroelastic domain reorientation (approximately 12 vol% of domains reorient at 3 times the coercive field, Ec) relative to the dense films (~3.5 vol% at 3Ec). Furthermore, the volume fraction of domain reorientation significantly exceeded that predicted by linear mixing rules. The high response of domain reorientation in porous films is discussed in the context of two mechanisms: local enhancement of the electric field near the pores and a reduction of substrate clamping resulting from the lowering of the film stiffness as a result of the porosity. Similar measurements during weak-field (subcoercive) amplitudes showed 0.6% volume fraction of domains reoriented for the porous films, which demonstrates that extrinsic effects contribute to the dielectric and piezoelectric properties. PMID:25585389

  2. Phase field simulation of domain switching dynamics in multiaxial lead zirconate titanate thin films

    NASA Astrophysics Data System (ADS)

    Britson, Jason

    The defining characteristic of ferroelectric materials is their ability to be switched between energetically equivalent polarization states. This behavior has led to an interest in ferroelectrics for a wide range of bulk and thin film applications such as mechanical actuators and ferroelectric random access memory devices. Ferroelectric switching depends on domain wall motion, however, and is critically influenced by the existence of defects such as dislocations and preexisting domains. Domain wall motion in thin film applications can be controlled by individual local defects due to the reduced length scale of the system. This dissertation describes the impact of preexisting ferroelastic domains and misfits dislocations in coherent (001)-oriented Pb(Zr0.2,Ti0.8)O3 (PZT) thin films on the switching response and domain structure. A phase field model based on the Landau-Ginzburg-Devonshire theory that accounts for the electrostatic and mechanical interactions is used to describe domain structures in ferroelectric PZT thin films. To solve the governing equations a semi-implicit Fourier-Spectral scheme is developed that accommodates boundary conditions appropriate to the thin film geometry. Errors are reduced in the solutions at the film edges through extensions to the model developed to correct the Fourier transform around stationary discontinuities at the thin film edges. This correction is shown to result in increased accuracy of the phase field model needed to appropriately describe dynamic switching responses in the thin film. Investigation of switching around preexisting ferroelastic domains showed these defects are strong obstacles to switching in PZT thin films. Directly above the ferroelastic domain the magnitude of the required nucleation bias underneath a tip-like electrode was found to be elevated compared to the required bias far from the domain. Locally both the piezoelectric and dielectric responses of the thin film were found to be suppressed, which is

  3. Titan!

    NASA Astrophysics Data System (ADS)

    Matson, Dennis L.

    2010-05-01

    Cassini-Huygens achieved Saturnian orbit on July 1, 2004. The first order of business was the safe delivery of the Huygens atmospheric probe to Titan that took place on January 14, 2005. Huygens descended under parachute obtaining observations all the way down to a safe landing. It revealed Titan for the first time. Stunning are the similarities between Titan and the Earth. Viewing the lakes and seas, the fluvial terrain, the sand dunes and other features through the hazy, nitrogen atmosphere, brings to mind the geological processes that created analogous features on the Earth. On Titan frozen water plays the geological role of rock; liquid methane takes the role of terrestrial water. The atmospheres of both Earth and Titan are predominately nitrogen gas. Titan's atmosphere contains 1.5% methane and no oxygen. The surface pressure on Titan is 1.5 times the Earth's. There are aerosol layers and clouds that come and go. Now, as Saturn proceeds along its solar orbit, the seasons are changing. The effects upon the transport of methane are starting to be seen. A large lake in the South Polar Region seems to be filling more as winter onsets. Will the size and number of the lakes in the South grow during winter? Will the northern lakes and seas diminish or dry up as northern summer progresses? How will the atmospheric circulation change? Much work remains not only for Cassini but also for future missions. Titan has many different environments to explore. These require more capable instruments and in situ probes. This work was conducted at the Jet Propulsion Laboratory, California Institute of Technology under contract with the National Aeronautics and Space Administration.

  4. A method to decrease the harmonic distortion in Mn-Zn ferrite/PZT and Ni-Zn ferrite/PZT layered composite rings exhibiting high magnetoelectric effects

    NASA Astrophysics Data System (ADS)

    Loyau, V.; Morin, V.; Fortineau, J.; LoBue, M.; Mazaleyrat, F.

    2015-10-01

    We have investigated the magnetoelectric (ME) effect in layered composite rings subjected to circumferential AC magnetic fields and DC magnetic fields in radial, axial, or circumferential directions. Bilayer samples were obtained combining different grades of commercial Mn-Zn ferrites or Ni-Zn ferrites with commercial lead zirconate titanate (PZT). Mn-Zn ferrites with low magnetostriction saturation ( λs<10-6 ) and low magneto-crystalline anisotropy constants show high ME capabilities when associated with PZT in ring structures. In certain conditions, these ME effects are higher than those obtained with Terfenol-D/PZT composites in the same layered ring structure. Magnetostrictive and mechanical characterizations have given results that explain these high ME performances. Nevertheless, Mn-Zn ferrite/PZT composites exhibit voltages responses with low linearity especially at high signal level. Based on the particular structure of the ME device, a method to decrease the nonlinear harmonic distortion of the ME voltages is proposed. Harmonic distortion analysis of ME voltages measured in different configurations allows us to explain the phenomenon.

  5. Ferroelectric domain switching of individual nanoscale grains in polycrystalline lead zirconate titanate thin films

    NASA Astrophysics Data System (ADS)

    Jing, Yuanyuan

    2011-12-01

    carried out in a polycrystalline PZT thin film. Using PDMs, 90° switching of individual grains is identified in addition to the expected 180° switching. What is noteworthy is that a significant number of grains undergo 90° switching in both switching and relaxation processes, a striking contrast with epitaxial thin films where only 180o switching have been reported. In chapter 5, the reason that a large amount of 90o switching occurred in a polycrystalline thin film is studied by experimentally characterizing the local microstructure. The preliminary results show a direct correlation between the crystal orientation of a chosen grain and its switching type, indicating that the switching of a grain is dominated by its orientation. For a minority of the grains, however, the neighboring grain should play a dominant role. The effects of neighboring grains on the center grain switching are studied in chapter 6. Switching loops are carried out at different positions within individual grains. A correlation across grain boundaries in the coercive bias was observed for almost all measured grain boundaries. Even inside the same grain, different grain boundaries can either facilitate or hinder the switching, depending on the grain boundary misorientation. Future work is discussed in chapter 7, including the non-deterministic domain switching in polycrystalline thin films, the influence of electron beams on the domain switching behavior, and the domain relaxation through 90o switching. In conclusion, a large fraction of 90o switching is found in a polycrystalline PZT thin film. The switching of an individual grain is found to be mainly determined by the grain orientation and the grain boundary misorientations. Grains orientated close to the [001] direction are more likely to go through a 90o switching than a 180o switching. Grain boundaries with different misorientation angles tend to either hinder or facilitate the switching of grains on both sides.

  6. Effects of acetylacetone additions on PZT thin film processing

    SciTech Connect

    Schwartz, R.W.; Assink, R.A.; Dimos, D.; Sinclair, M.B.; Boyle, T.J.; Buchheit, C.D.

    1995-02-01

    Sol-gel processing methods are frequently used for the fabrication of lead zirconate titanate (PZT) thin films for many electronic applications. Our standard approach for film fabrication utilizes lead acetate and acetic acid modified metal alkoxides of zirconium and titanium in the preparation of our precursor solutions. This report highlights some of our recent results on the effects of the addition of a second chelating ligand, acetylacetone, to this process. The authors discuss the changes in film drying behavior, densification and ceramic microstructure which accompany acetylacetone additions to the precursor solution and relate the observed variations in processing behavior to differences in chemical precursor structure induced by the acetylacetone ligand. Improvements in thin film microstructure, ferroelectric and optical properties are observed when acetylacetone is added to the precursor solution.

  7. Fabrication and Evaluation of One-Axis Oriented Lead Zirconate Titanate Films Using Metal-Oxide Nanosheet Interface Layer

    NASA Astrophysics Data System (ADS)

    Minemura, Yoshiki; Nagasaka, Kohei; Kiguchi, Takanori; Konno, Toyohiko J.; Funakubo, Hiroshi; Uchida, Hiroshi

    2013-09-01

    Nanosheet Ca2Nb3O20 (ns-CN) layers with pseudo-perovskite-type crystal configuration were applied on the surface of polycrystalline metal substrates to achieve preferential crystal orientation of Pb(Zr,Ti)O3 (PZT) films for the purpose of enhanced ferroelectricity comparable to that of epitaxial thin films. PZT films with tetragonal symmetry (Zr/Ti=0.40:0.60) were fabricated by chemical solution deposition (CSD) on ns-CN-buffered Inconel 625 and SUS 316L substrates, while ns-CN was applied on the the substrates by dip-coating. The preferential crystal growth on the ns-CN layer can be achieved by favorable lattice matching between (001)/(100)PZT and (001)ns-CN planes. The degree of (001) orientation was increased for PZT films on ns-CN/Inconel 625 and ns-CN/SUS 316L substrates, whereas randomly-oriented PZT films with a lower degree of (001) orientation were grown on bare and Inconel 625 films. Enhanced remanent polarization of 60 µC/cm2 was confirmed for the PZT films on ns-CN/metal substrates, ascribed to the preferential alignment of the polar [001] axis normal to the substrate surface, although it also suffered from higher coercive field above 500 kV/cm caused by PZT/metal interfacial reaction.

  8. In situ transmission electron microscopy study of the electric field-induced transformation of incommensurate modulations in a Sn-modified lead zirconate titanate ceramic

    NASA Astrophysics Data System (ADS)

    He, H.; Tan, X.

    2004-10-01

    Electric field-induced transformation of incommensurate modulations in a Sn-modified lead zirconate titanate ceramic was investigated with an electric field in situ transmission electron microscopy technique. It is found that the spacing between the (1/x){110} satellite spots and the fundamental reflections do not change with external electric field, indicating that the modulation wavelength stays constant under applied field. The intensity of these satellites starts to decrease when the field level reaches a critical value. Further increase in the field strength eventually leads to the complete disappearance of the satellite reflections. In addition, the 1/2 {111}-type superlattice reflections showed no response to electrical stimuli.

  9. Y3Fe5O12/Na,Bi,Sr-doped PZT particulate magnetoelectric composites

    NASA Astrophysics Data System (ADS)

    Lisnevskaya, I. V.; Bobrova, I. A.; Lupeiko, T. G.; Agamirzoeva, M. R.; Myagkaya, K. V.

    2016-05-01

    Magnetoelectric (ME) composites of Na, Bi, Sr substituted lead zirconate titanate (PZT) and yttrium iron garnet having representative formula (100-х) wt% Na,Bi,Sr-doped PZT (PZTNB-1)+х wt% Y3Fe5O12 (YIG) with х=10-90 were manufactured using powdered components obtained through sol-gel processes. It is shown that the decrease in sintering temperature provided by the use of finely dispersed PZTNB-1 and YIG powders allows to significantly reduce content of fluorite-like foreign phase based on zirconium oxide, which forms due to the interfacial interaction during heat treatment and becomes stabilized by yttrium oxide. Connectivity has considerable effect on the value of ME coefficient of composite ceramics. With the same x value, ΔЕ/ΔН characteristic decreases when changing from 0-3-type structured composites (PZT grains embedded in ferrite matrix) to 3-3-(interpenetrating network of two phases) and especially 3-0-type samples (YIG grains embedded in PZT matrix); in the last case this can be attributed to the substrate clamping effect when ferrite grains are clamped with piezoelectric matrix. ΔЕ/ΔН value of 0-3 composites with х=40-60 wt% was found to be ∼1.6 mV/(cm Oe).

  10. Evaluation of additive element to improve PZT piezoelectricity by using first-principles calculation

    NASA Astrophysics Data System (ADS)

    Yasoda, Yutaka; Uetsuji, Yasutomo; Tsuchiya, Kazuyoshi

    2015-12-01

    Recently, piezoelectric material has a very important potential for functional material which configure Bio-MEMS (Biological Micro Electro Mechanical Systems) actuator and sensor. Specifically, in implementation of piezoelectric material for Bio-MEMS, thin film fabrication by sputtering method is made from the viewpoint of miniaturization. Furthermore, in piezoelectric material, perovskite type material composed of ABO3 has a high piezoelectricity. Then, PZT (Lead Zirconate Titanate) as the perovskite type piezoelectric material is widely used since it is easy to produce and has high piezoelectricity. PZT has zirconium or titanium in the B site of ABO3 structure. PZT has the features such as physical properties to greatly change by change in the B site composition ratio of zirconium and titanium. Thus, the B site greatly influences physical properties and therefore function improvement by additive element is tried widely. However, experimental method to lack in economy and quantitativeness is mainstream. Therefore, application of the result is difficult and new evaluation method of B site additive element for sputtering fabrication is necessary. Accordingly, in this research, search of an additive element at low cost and quantitative from the viewpoint of energy by first-principles calculation. First of all, the additive elements which capable of substituting for a B site of PZT were searched. Next, change of piezoelectricity was evaluated by change of crystal structure in a PZT system was introduced an additive element that substitution of the B site was possible. As a result, additive elements for the PZT B site capable of improving piezoelectricity were determined.

  11. PZT Thin-Film Micro Probe Device with Dual Top Electrodes

    NASA Astrophysics Data System (ADS)

    Luo, Chuan

    Lead zirconate titanate (PZT) thin-film actuators have been studied intensively for years because of their potential applications in many fields. In this dissertation, a PZT thin-film micro probe device is designed, fabricated, studied, and proven to be acceptable as an intracochlear acoustic actuator. The micro probe device takes the form of a cantilever with a PZT thin-film diaphragm at the tip of the probe. The tip portion of the probe will be implanted in cochlea later in animal tests to prove its feasibility in hearing rehabilitation. The contribution of the dissertation is three-fold. First, a dual top electrodes design, consisting of a center electrode and an outer electrode, is developed to improve actuation displacement of the PZT thin-film diaphragm. The improvement by the dual top electrodes design is studied via a finite element model. When the dimensions of the dual electrodes are optimized, the displacement of the PZT thin-film diaphragm increases about 30%. A PZT thin-film diaphragm with dual top electrodes is fabricated to prove the concept, and experimental results confirm the predictions from the finite element analyses. Moreover, the dual electrode design can accommodate presence of significant residual stresses in the PZT thin-film diaphragm by changing the phase difference between the two electrodes. Second, a PZT thin-film micro probe device is fabricated and tested. The fabrication process consists of PZT thin-film deposition and deep reactive ion etching (DRIE). The uniqueness of the fabrication process is an automatic dicing mechanism that allows a large number of probes to be released easily from the wafer. Moreover, the fabrication is very efficient, because the DRIE process will form the PZT thin-film diaphragm and the special dicing mechanism simultaneously. After the probes are fabricated, they are tested with various possible implantation depths (i.e., boundary conditions). Experimental results show that future implantation depths

  12. An experimental investigation of lead zirconate titanate--epoxy-multi-walled carbon nanotube bulk and flexible thick film composites

    NASA Astrophysics Data System (ADS)

    Banerjee, Sankha

    Piezoelectric sensors and actuators are needed for a wide range of applications from physiological measurement to industrial monitoring systems. Sensors that can be easily integrated with the host, while maintaining high sensitivity and reliability over a wide range of frequencies are not readily feasible and economical with homogenous piezoelectric materials. It is well known that two-phase piezoelectric-epoxy composites offer several benefits over their single phase counterparts, as the properties of the constituent phases combine to improve the range of applicability. However, the piezoelectric properties of these materials suffer from the electrically insulating properties of the epoxy matrix. The electrical properties of the matrix may be enhanced by including electrically conducting inclusions however, less is known about the mechanisms that drive the changes in these properties. Hence, this experimental investigation of sensor materials builds on the previous work in two-phase piezoelectric composites, where the aims are to understand the roles that specific fabrication parameters and inclusion composition play in determining the piezoelectric and dielectric performance the aforementioned composites. The materials under investigation will be comprised of Lead Zirconate Titanate, Epofix Cold-Setting Embedding Resin and multi-walled carbon nanotubes, i.e. the piezoelectric, epoxy and electrical inclusions respectively. Our work suggests that inclusion of MWCNTs enhances the piezoelectric and dielectric properties with increasing volume fraction below the percolation threshold. This work seeks to understand how the processing parameters: poling temperature, poling type and particle distribution influence the contact resistance, space charge double layer at the piezoelectric and conductor interfaces and electric field intensity at the piezoelectric boundary, which all ultimately dictate the piezoelectric and dielectric performance of the composite materials

  13. Interface magnetoelectric effect in the layered heterostructures with Co layers on the polished and ion-beam planarized ceramic PZT substrates

    NASA Astrophysics Data System (ADS)

    Stognij, Alexandre I.; Novitskii, Nickolaj; Poddubnaya, Natalia; Sharko, Sergei; Ketsko, Valerij; Mikhailov, Vladimir; Dyakonov, Vladimir; Szymczak, Henryk

    2015-01-01

    The low-frequency room temperature interface magnetoelectric (ME) effect was observed in the layered heterostructures comprising the ferromagnetic (FM) Co layers and ferroelectric (FE) ceramic substrates on the base of lead zirconate titanate PbZr0.45Ti0.55O3 (PZT). The Co films 1-12 μm in thickness were deposited by ion-beam sputtering/deposition technics onto the 400 μm PZT substrates. Results of X-ray, magnetic and ME experiments have shown the existence of ME effect in Co/PZT/Co and (Co/PZT/Co)3 heterostructures obtained by the above mentioned techniques being independent on ferromagnetic/ferroelectric interface roughness. The values of ME voltage coefficient in heterostructures with ion-beam planarized PZT surfaces are much higher than that in heterostructures with mechanochemically polished ceramic substrate surfaces. The heterostructures possess ME effect of the same order as those obtained by means of the mechanical bonding of FM and FE sheets with organic binders and have the typical ME hysteresis curves. The structures obtained are perspective for application as energy-independent elements in magnetic field sensors and magnetic memory.

  14. Performance of PZT stacks under high-field electric cycling at various temperatures in heavy-duty diesel engine fuel injectors

    NASA Astrophysics Data System (ADS)

    Wang, Hong; Lee, Sung-Min; Lin, Hua-Tay; Stafford, Randy

    2016-04-01

    Testing and characterization of large prototype lead zirconate titanate (PZT) stacks present substantial technical challenges to electronic systems. The work in this study shows that an alternative approach can be pursued by using subunits extracted from prototype stacks. Piezoelectric and dielectric integrity was maintained even though the PZT plate specimens experienced an additional loading process involved with the extraction after factory poling. Extracted 10-layer plate specimens were studied by an electric cycle test under an electric field of 3.0/0.0 kV/mm, 100 Hz to 108 cycles, both at room temperature (22°C) and at 50°C. The elevated temperature had a defined impact on the fatigue of PZT stacks. About 48 and 28% reductions were observed in the piezoelectric and dielectric coefficients, respectively, after 108 cycles at 50°C, compared with reductions of 25 and 15% in the respective coefficients at 22°C. At the same time, the loss tangent varied to a limited extent. The evolution of PZT-electrode interfacial layers or nearby dielectric layers should account for the difference in the fatigue rates of piezoelectric and dielectric coefficients. But the basic contribution to observed fatigue may result from the buildup of a bias field that finally suppressed the motion of the domain walls. Finally, monitoring of dielectric coefficients can be an effective tool for on-line lifetime prediction of PZT stacks in service if a failure criterion is defined properly.

  15. Field-enhanced piezoelectric deformation during the high temperature/low temperature rhombohedral (FERh/FERL) phase transformation for tin modified lead zirconate titanate ceramics

    NASA Astrophysics Data System (ADS)

    Yang, Pin; Moore, Roger H.; Burns, George R.

    2002-06-01

    An unusual field-enhanced piezoelectric deformation near the FERH/FERL structural phase transformation was observed in a tin modified lead zirconate titanate solid solution. In addition to the typical field-induced domain reorientation and the piezoelectric strain, this additional field-enhanced deformation only observed near the phase transformation increases linearly with external electric field strength. A 78% increase in field-enhanced strain was observed at a field strength of 32 kV/cm. Comparison of the dielectric susceptibility at low and high field conditions suggests that the observed unusual behavior is created by a field-induced lattice softening during the structural phase transformation. Experimental observations on the field-induced softening phenomena are reported.

  16. An in situ diffraction study of domain wall motion contributions to the frequency dispersion of the piezoelectric coefficient in lead zirconate titanate

    SciTech Connect

    Seshadri, Shruti B.; Prewitt, Anderson D.; Jones, Jacob L.; Studer, Andrew J.; Damjanovic, Dragan

    2013-01-28

    The contribution of non-180 Degree-Sign domain wall displacement to the frequency dependence of the longitudinal piezoelectric coefficient has been determined experimentally in lead zirconate titanate using time-resolved, in situ neutron diffraction. Under subcoercive electric fields of low frequencies, approximately 3% to 4% of the volume fraction of non-180 Degree-Sign domains parallel to the field experienced polarization reorientation. This subtle non-180 Degree-Sign domain wall motion directly contributes to 64% to 75% of the magnitude of the piezoelectric coefficient. Moreover, part of the 33 pm/V decrease in piezoelectric coefficient across 2 orders of magnitude in frequency is quantitatively attributed to non-180 Degree-Sign domain wall motion effects.

  17. Optoenergy storage, stimulated processes in optical amplification with electro-optic ceramic gain media of Nd3+ doped lanthanum lead zirconate titanate

    NASA Astrophysics Data System (ADS)

    Wu, Ye; Zhao, Hua; Zou, Yingyin K.; Chen, Xuesheng; Bartolo, Baldassare Di; Zhang, Jingwen W.

    2011-08-01

    Optical amplification was observed in electro-optic (EO) ceramic plates of neodymium doped lanthanum-modified lead zirconate titanate (Nd3+:PLZT), when the pumping and seeding beams are not overlapped temporarily. This striking feature in the gain measurement and the accompanying slowly trailing-off both seen in the optical amplification as well as in the lasing action are satisfactorily explained by electron releasing from the rich vacancy-based carrier traps in the intrinsically disordered ceramics, i.e., the consecutively optical, thermal stimuli are found responsible for the long persistent optoenergy storage, and consequently the slow response of the gain dynamics. These findings in optical amplification, the slowly trailing-off, and the underlying mechanism have opened a new way of developing novel controllable optical devices. The model thus established could serve as a guide in design and refinement of a new generation of products out of this excellent, well commercialized EO PLZT ceramics family and similar others.

  18. Effects of postdeposition annealing on the dielectric properties of antiferroelectric lanthanum-doped lead zirconate stannate titanate thin films derived from pulsed laser deposition

    NASA Astrophysics Data System (ADS)

    Yao, Yingbang; Lu, S. G.; Chen, Haydn; Wong, K. H.

    2004-11-01

    Lanthanum-doped lead zirconate stannate titanate antiferroelectric thin films were deposited onto Pt-buffered silicon substrates using the pulsed laser deposition method. The deposition temperature was 570°C. The postdeposition annealing process was carried out in an oxygen-flow tube furnace at temperatures ranging from 650 to 800°C for a duration of 30min; its effects were studied through the variations of the microstructure as well as the electrical and dielectric properties. It was found that an appropriate annealing process at temperatures above 700°Ccould substantially improve the dielectric properties. However, annealing beyond 800°C caused the film properties to deteriorate severely. Explanations were given with regard to the microstructure-property relationship.

  19. Miniature Cryogenic Valves for a Titan Lake Sampling System

    NASA Technical Reports Server (NTRS)

    Sherrit, Stewart; Zimmerman, Wayne; Takano, Nobuyuki; Avellar, Louisa

    2014-01-01

    The Cassini mission has revealed Titan to be one of the most Earthlike worlds in the Solar System complete with many of the same surface features including lakes, river channels, basins, and dunes. But unlike Earth, the materials and fluids on Titan are composed of cryogenic organic compounds with lakes of liquid methane and ethane. One of the potential mission concepts to explore Titan is to land a floating platform on one of the Titan Lakes and determine the local lake chemistry. In order to accomplish this within the expected mass volume and power budgets there is a need to pursue the development for a low power lightweight cryogenic valves which can be used along with vacuum lines to sample lake liquid and to distribute to various instruments aboard the Lander. To meet this need we have initiated the development of low power cryogenic valves and actuators based on a single crystal piezoelectric flextensional stacks produced by TRS Ceramics Inc. Since the origin of such high electromechanical properties of Relaxor-PT single crystals is due to the polarization rotation effect, (i.e., intrinsic contributions), the strain per volt decrease at cryogenic temperatures is much lower than in standard Lead Zirconate Titanate (PZT) ceramics. This makes them promising candidates for cryogenic actuators with regards to the stroke for a given voltage. This paper will present our Titan Lake Sampling and Sample Handling system design and the development of small cryogenic piezoelectric valves developed to meet the system specifications.

  20. Dependence of the ferroelectric properties of modified spin-coating-derived PZT thick films on the crystalline orientation

    NASA Astrophysics Data System (ADS)

    Annapureddy, Venkateswarlu; Choi, Jong-Jin; Kim, Jong-Woo; Hahn, Byung-Dong; Ahn, Cheol-Woo; Ryu, Jungho

    2016-06-01

    The effects of crystalline orientation on the ferroelectric properties of lead zirconate titanate (PZT) thick films deposited on (111)-oriented Pt/Ti/SiO2/Si substrates by using a modified spincoating method have been studied. The texture and the microstructure of the thick films were characterized by using X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis, respectively. The XRD results implied that the texture of the PZT films was sensitive to the pyrolysis conditions after spin-coating, but less dependent on the film's thickness. The texture had mainly a (111)-orientation for pyrolysis temperatures from 330 to 400 °C, and changes in the (100)- orientation occurred for pyrolysis temperatures at or above 450 °C after annealing at 650 °C for 5 min. The formation of a preferred texture could be explained by using the intermetallic phases and the internal stress energies between the substrate and the film. The ferroelectric properties of the PZT films fabricated by using this method have been found to be enhanced as compared to those of the PZT films fabricated by using the conventional spin-coating method and to be correlated to the microstructure of the film.

  1. Lanthanide-Assisted Deposition of Strongly Electro-optic PZT Thin Films on Silicon: Toward Integrated Active Nanophotonic Devices.

    PubMed

    George, J P; Smet, P F; Botterman, J; Bliznuk, V; Woestenborghs, W; Van Thourhout, D; Neyts, K; Beeckman, J

    2015-06-24

    The electro-optical properties of lead zirconate titanate (PZT) thin films depend strongly on the quality and crystallographic orientation of the thin films. We demonstrate a novel method to grow highly textured PZT thin films on silicon using the chemical solution deposition (CSD) process. We report the use of ultrathin (5-15 nm) lanthanide (La, Pr, Nd, Sm) based intermediate layers for obtaining preferentially (100) oriented PZT thin films. X-ray diffraction measurements indicate preferentially oriented intermediate Ln2O2CO3 layers providing an excellent lattice match with the PZT thin films grown on top. The XRD and scanning electron microscopy measurements reveal that the annealed layers are dense, uniform, crack-free and highly oriented (>99.8%) without apparent defects or secondary phases. The EDX and HRTEM characterization confirm that the template layers act as an efficient diffusion barrier and form a sharp interface between the substrate and the PZT. The electrical measurements indicate a dielectric constant of ∼650, low dielectric loss of ∼0.02, coercive field of 70 kV/cm, remnant polarization of 25 μC/cm(2), and large breakdown electric field of 1000 kV/cm. Finally, the effective electro-optic coefficients of the films are estimated with a spectroscopic ellipsometer measurement, considering the electric field induced variations in the phase reflectance ratio. The electro-optic measurements reveal excellent linear effective pockels coefficients of 110 to 240 pm/V, which makes the CSD deposited PZT thin film an ideal candidate for Si-based active integrated nanophotonic devices. PMID:26043103

  2. Feasibility of PZT ceramics for impact damage detection in composite structures

    NASA Astrophysics Data System (ADS)

    Dib, Gerges; Koricho, Ermias; Karpenko, Oleksii; Haq, Mahmood; Udpa, Lalita; Udpa, Satish S.

    2015-03-01

    Fiber reinforced plastic composites are becoming widely used in vehicles and airframe structures due to their high strength to weight ratio. However unlike metals, the multilayered composite structures are more susceptible to damage mechanisms such as disbonds and delaminations due to impacts. It is often difficult to visually detect the damage. Lead-Zirconate-Titanate (PZT) thin films are becoming popular for in-situ structural health monitoring due to their small size, high piezoelectric coupling coefficient, and ease of surface-mounting and/or embedding in composite structures. A network of such transducers could be utilized for damage detection using guided wave techniques, impedance techniques, or passive impact detection techniques. However, the PZT films are subject to the same impact probabilities that the structure encounters. If the transducers fail due to the subjected impacts, they can result in false readings and ultimately failing to correctly detect damage in the structure. This paper presents a feasibility study using the guided wave S0 mode for detecting impact damage. The health of the structure is quantified using guided wave measurements, and the PZT health is monitored using impedance methods.

  3. Low frequency acoustic energy harvesting using PZT piezoelectric plates in a straight tube resonator

    NASA Astrophysics Data System (ADS)

    Li, Bin; You, Jeong Ho; Kim, Yong-Joe

    2013-05-01

    A novel and practical acoustic energy harvesting mechanism to harvest traveling sound at low audible frequency is introduced and studied both experimentally and numerically. The acoustic energy harvester in this study contains a quarter-wavelength straight tube resonator with lead zirconate titanate (PZT) piezoelectric cantilever plates placed inside the tube. When the tube resonator is excited by an incident sound at its acoustic resonance frequency, the amplified acoustic pressure inside the tube drives the vibration motions of piezoelectric plates, resulting in the generation of electricity. To increase the total voltage and power, multiple PZT plates were placed inside the tube. The number of PZT plates to maximize the voltage and power is limited due to the interruption of air particle motion by the plates. It has been found to be more beneficial to place the piezoelectric plates in the first half of the tube rather than along the entire tube. With an incident sound pressure level of 100 dB, an output voltage of 5.089 V was measured. The output voltage increases linearly with the incident sound pressure. With an incident sound pressure of 110 dB, an output voltage of 15.689 V and a power of 12.697 mW were obtained. The corresponding areal and volume power densities are 0.635 mW cm-2 and 15.115 μW cm-3, respectively.

  4. Development of fine scale PZT ceramic fiber/polymer shell composite transducers

    SciTech Connect

    Livneh, S.S.; Janas, V.F.; Safari, A.

    1995-07-01

    The relic processing technique was used to fabricate fine-scale piezoelectric lead zirconate titanate (PZT) ceramic fiber/polymer shell composites. In this technique sacrificial activated carbon fabrics were soaked in a PZT precursor solution, dried, and heat treated to form piezoceramic relics. Relics were embedded with polymer, which was allowed to cure, and the resulting composites were polished, electroded, and poled. Different facets of the composite-forming process were examined: structural modifications, soaking, firing, and polymer impregnation. The physical and electromechanical properties of the unique resulting composite were evaluated. Optimized PZT shell composites with 39 vol% ceramic exhibited the following property values: K{approximately}200, tan {delta} {approximately} 5.5%, d{sub 33} {approximately} 290 pC/N, d{sub h} {approximately} 100 pC/N, d{sub h}g{sub h} {approximately} 6000 {times} 10 {sup {minus}15} m{sup 2}/N, k{sub p} {approximately} 0.19, and k{sub t} {approximately} 0.28.

  5. Design Optimization of PZT-Based Piezoelectric Cantilever Beam by Using Computational Experiments

    NASA Astrophysics Data System (ADS)

    Kim, Jihoon; Park, Sanghyun; Lim, Woochul; Jang, Junyong; Lee, Tae Hee; Hong, Seong Kwang; Song, Yewon; Sung, Tae Hyun

    2016-08-01

    Piezoelectric energy harvesting is gaining huge research interest since it provides high power density and has real-life applicability. However, investigative research for the mechanical-electrical coupling phenomenon remains challenging. Many researchers depend on physical experiments to choose devices with the best performance which meet design objectives through case analysis; this involves high design costs. This study aims to develop a practical model using computer simulations and to propose an optimized design for a lead zirconate titanate (PZT)-based piezoelectric cantilever beam which is widely used in energy harvesting. In this study, the commercial finite element (FE) software is used to predict the voltage generated from vibrations of the PZT-based piezoelectric cantilever beam. Because the initial FE model differs from physical experiments, the model is calibrated by multi-objective optimization to increase the accuracy of the predictions. We collect data from physical experiments using the cantilever beam and use these experimental results in the calibration process. Since dynamic analysis in the FE analysis of the piezoelectric cantilever beam with a dense step size is considerably time-consuming, a surrogate model is employed for efficient optimization. Through the design optimization of the PZT-based piezoelectric cantilever beam, a high-performance piezoelectric device was developed. The sensitivity of the variables at the optimum design is analyzed to suggest a further improved device.

  6. Design Optimization of PZT-Based Piezoelectric Cantilever Beam by Using Computational Experiments

    NASA Astrophysics Data System (ADS)

    Kim, Jihoon; Park, Sanghyun; Lim, Woochul; Jang, Junyong; Lee, Tae Hee; Hong, Seong Kwang; Song, Yewon; Sung, Tae Hyun

    2016-04-01

    Piezoelectric energy harvesting is gaining huge research interest since it provides high power density and has real-life applicability. However, investigative research for the mechanical-electrical coupling phenomenon remains challenging. Many researchers depend on physical experiments to choose devices with the best performance which meet design objectives through case analysis; this involves high design costs. This study aims to develop a practical model using computer simulations and to propose an optimized design for a lead zirconate titanate (PZT)-based piezoelectric cantilever beam which is widely used in energy harvesting. In this study, the commercial finite element (FE) software is used to predict the voltage generated from vibrations of the PZT-based piezoelectric cantilever beam. Because the initial FE model differs from physical experiments, the model is calibrated by multi-objective optimization to increase the accuracy of the predictions. We collect data from physical experiments using the cantilever beam and use these experimental results in the calibration process. Since dynamic analysis in the FE analysis of the piezoelectric cantilever beam with a dense step size is considerably time-consuming, a surrogate model is employed for efficient optimization. Through the design optimization of the PZT-based piezoelectric cantilever beam, a high-performance piezoelectric device was developed. The sensitivity of the variables at the optimum design is analyzed to suggest a further improved device.

  7. Fabrication and performance of a single-crystal lead magnesium niobate-lead titanate cylindrical hydrophone.

    PubMed

    Brown, Jeremy A; Dunphy, Kevin; Leadbetter, Jeff R; Adamson, Robert B A; Beslin, Olivier

    2013-08-01

    The development of a piezoelectric hydrophone based on lead magnesium niobate-lead titanate [PbMg1/3Nb2/3O3-PbTiO3 (PMN-PT)] single-crystal piezoelectric as the hydrophone substrate is reported. Although PMN-PT can possess much higher piezoelectric sensitivity than traditional lead zirconate titanate (PZT) piezoelectrics, it is highly anisotropic and therefore there is a large gain in sensitivity only when the crystal structure is oriented in a specific direction. Because of this, simply replacing the PZT substrate with a PMN-PT cylinder is not an optimal solution because the crystal orientation does not uniformly align with the circumferential axis of the hydrophone. Therefore, a composite hydrophone that maintains the optimal crystal axis around the hydrophone circumference has been developed. An 11.3 mm diameter composite hydrophone cylinder was fabricated from a single <110> cut PMN-PT rectangular plate. Solid end caps were applied to the cylinder and the sensitivity was directly compared with a solid PZT-5A cylindrical hydrophone of equal dimensions in a hydrophone test tank. The charge sensitivity showed a 9.1 dB improvement over the PZT hydrophone and the voltage sensitivity showed a 3.5 dB improvement. This was in good agreement with the expected theoretical improvements of 10.1 and 4.5 dB, respectively. PMID:23927102

  8. Photovoltaic enhancement due to surface-plasmon assisted visible-light absorption at the inartificial surface of lead zirconate-titanate film

    NASA Astrophysics Data System (ADS)

    Zheng, Fengang; Zhang, Peng; Wang, Xiaofeng; Huang, Wen; Zhang, Jinxing; Shen, Mingrong; Dong, Wen; Fang, Liang; Bai, Yongbin; Shen, Xiaoqing; Sun, Hua; Hao, Jianhua

    2014-02-01

    PZT film of 300 nm thickness was deposited on tin indium oxide (ITO) coated quartz by a sol-gel method. Four metal electrodes, such as Pt, Au, Cu and Ag, were used as top electrodes deposited on the same PZT film by sputtering at room temperature. In ITO-PZT-Ag and ITO-PZT-Au structures, the visible light (400-700 nm) can be absorbed partially by a PZT film, and the maximum efficiency of photoelectric conversion of the ITO-PZT-Ag structure was enhanced to 0.42% (100 mW cm-2, AM 1.5G), which is about 15 times higher than that of the ITO-PZT-Pt structure. Numerical simulations show that the natural random roughness of polycrystalline-PZT-metal interface can offer a possibility of coupling between the incident photons and SPs at the metal surface. The coincidence between the calculated SP properties and the measured EQE spectra reveals the SP origin of the photovoltaic enhancement in these ITO-PZT-metal structures, and the improved photocurrent output is caused by the enhanced optical absorption in the PZT region near the metal surface, rather than by the direct charge-transfer process between two materials.PZT film of 300 nm thickness was deposited on tin indium oxide (ITO) coated quartz by a sol-gel method. Four metal electrodes, such as Pt, Au, Cu and Ag, were used as top electrodes deposited on the same PZT film by sputtering at room temperature. In ITO-PZT-Ag and ITO-PZT-Au structures, the visible light (400-700 nm) can be absorbed partially by a PZT film, and the maximum efficiency of photoelectric conversion of the ITO-PZT-Ag structure was enhanced to 0.42% (100 mW cm-2, AM 1.5G), which is about 15 times higher than that of the ITO-PZT-Pt structure. Numerical simulations show that the natural random roughness of polycrystalline-PZT-metal interface can offer a possibility of coupling between the incident photons and SPs at the metal surface. The coincidence between the calculated SP properties and the measured EQE spectra reveals the SP origin of the

  9. Adjustable grazing incidence x-ray optics based on thin PZT films

    NASA Astrophysics Data System (ADS)

    Cotroneo, Vincenzo; Davis, William N.; Marquez, Vanessa; Reid, Paul B.; Schwartz, Daniel A.; Johnson-Wilke, Raegan L.; Trolier-McKinstry, Susan E.; Wilke, Rudeger H. T.

    2012-10-01

    The direct deposition of piezoelectric thin films on thin substrates offers an appealing technology for the realization of lightweight adjustable mirrors capable of sub-arcsecond resolution. This solution will make it possible to realize X-ray telescopes with both large effective area and exceptional angular resolution and, in particular, it will enable the realization of the adjustable optics for the proposed mission Square Meter Arcsecond Resolution X-ray Telescope (SMART-X). In the past years we demonstrated for the first time the possibility of depositing a working piezoelectric thin film (1-5 um) made of lead-zirconate-titanate (PZT) on glass. Here we review the recent progress in film deposition and influence function characterization and comparison with finite element models. The suitability of the deposited films is analyzed and some constrains on the piezoelectric film performances are derived. The future steps in the development of the technology are described.

  10. Identification of crystalline elastic anisotropy in PZT ceramics from in-situ blocking stress measurements

    SciTech Connect

    Daniel, L.; Hall, D. A.; Withers, P. J.; Webber, K. G.; King, A.

    2014-05-07

    High energy x-ray diffraction measurements of lattice strains were performed on a rhombohedral Lead Zirconate Titanate ceramic (PZT 55-45) under combinations of applied electric field and compressive stress. These measurements allow the construction of blocking stress curves for different sets of crystallographic orientations which reflect the single crystal elastic anisotropy. A micro-mechanical interpretation of the results is then proposed. Assuming cubic symmetry for the crystalline elastic stiffness tensor and isotropy for the macroscopic elastic properties, the elastic properties of the single crystal are extracted from the measured data. An anisotropy ratio close to 0.3 is found (compared to 1 for isotropic materials). The high level of anisotropy found in this work suggests that crystalline elastic anisotropy should not be neglected in the modelling of ferroelectric materials.

  11. Damage Evaluation Based on a Wave Energy Flow Map Using Multiple PZT Sensors

    PubMed Central

    Liu, Yaolu; Hu, Ning; Xu, Hong; Yuan, Weifeng; Yan, Cheng; Li, Yuan; Goda, Riu; Alamusi; Qiu, Jinhao; Ning, Huiming; Wu, Liangke

    2014-01-01

    A new wave energy flow (WEF) map concept was proposed in this work. Based on it, an improved technique incorporating the laser scanning method and Betti's reciprocal theorem was developed to evaluate the shape and size of damage as well as to realize visualization of wave propagation. In this technique, a simple signal processing algorithm was proposed to construct the WEF map when waves propagate through an inspection region, and multiple lead zirconate titanate (PZT) sensors were employed to improve inspection reliability. Various damages in aluminum and carbon fiber reinforced plastic laminated plates were experimentally and numerically evaluated to validate this technique. The results show that it can effectively evaluate the shape and size of damage from wave field variations around the damage in the WEF map. PMID:24463430

  12. Large Stroke Vertical PZT Microactuator With High-Speed Rotational Scanning

    PubMed Central

    Qiu, Zhen; Rhee, Choong-Ho; Choi, Jongsoo; Wang, Thomas D.; Oldham, Kenn R.

    2014-01-01

    A thin-film piezoelectric microactuator using a novel combination of active vertical translational scanning and passive resonant rotational scanning is presented. Thin-film lead-zirconate-titanate unimorph bending beams surrounding a central platform provide nearly 200-μm displacement at 18 V with bandwidth greater than 200 Hz. Inside the platform, a mirror mount, or mirror surface, supported by silicon dioxide spring beams can be excited to resonance by low-voltage; high-frequency excitation of the outer PZT beams. Over ±5.5° mechanical resonance is obtained at 3.8 kHz and ±2 V. The combination of large translational vertical displacements and high-speed rotational scanning is intended to support real-time cross-sectional imaging in a dual axes confocal endomicroscope. PMID:25506187

  13. Photovoltaic enhancement due to surface-plasmon assisted visible-light absorption at the inartificial surface of lead zirconate-titanate film.

    PubMed

    Zheng, Fengang; Zhang, Peng; Wang, Xiaofeng; Huang, Wen; Zhang, Jinxing; Shen, Mingrong; Dong, Wen; Fang, Liang; Bai, Yongbin; Shen, Xiaoqing; Sun, Hua; Hao, Jianhua

    2014-03-01

    PZT film of 300 nm thickness was deposited on tin indium oxide (ITO) coated quartz by a sol-gel method. Four metal electrodes, such as Pt, Au, Cu and Ag, were used as top electrodes deposited on the same PZT film by sputtering at room temperature. In ITO-PZT-Ag and ITO-PZT-Au structures, the visible light (400-700 nm) can be absorbed partially by a PZT film, and the maximum efficiency of photoelectric conversion of the ITO-PZT-Ag structure was enhanced to 0.42% (100 mW cm(-2), AM 1.5G), which is about 15 times higher than that of the ITO-PZT-Pt structure. Numerical simulations show that the natural random roughness of polycrystalline-PZT-metal interface can offer a possibility of coupling between the incident photons and SPs at the metal surface. The coincidence between the calculated SP properties and the measured EQE spectra reveals the SP origin of the photovoltaic enhancement in these ITO-PZT-metal structures, and the improved photocurrent output is caused by the enhanced optical absorption in the PZT region near the metal surface, rather than by the direct charge-transfer process between two materials. PMID:24477668

  14. Effects of high energy x ray and proton irradiation on lead zirconate titanate thin films' dielectric and piezoelectric response

    SciTech Connect

    Bastani, Y.; Cortes-Pena, A. Y.; Wilson, A. D.; Gerardin, S.; Bagatin, M.; Paccagnella, A.; Bassiri-Gharb, N.

    2013-05-13

    The effects of irradiation by X rays and protons on the dielectric and piezoelectric response of highly (100)-textured polycrystalline Pb(Zr{sub x}Ti{sub 1-x})O{sub 3} (PZT) thin films have been studied. Low-field dielectric permittivity, remanent polarization, and piezoelectric d{sub 33,f} response all degraded with exposure to radiation, for doses higher than 300 krad. At first approximation, the degradation increased at higher radiation doses, and was stronger in samples exposed to X rays, compared to the proton-irradiated ones. Nonlinear and high-field dielectric characterization suggest a radiation-induced reduction of the extrinsic contributions to the response, attributed to increased pinning of the domain walls by the radiation-induced point defects.

  15. A PZT-based smart aggregate for compressive seismic stress monitoring

    NASA Astrophysics Data System (ADS)

    Hou, S.; Zhang, H. B.; Ou, J. P.

    2012-10-01

    A PZT-based smart aggregate (SA) for compressive seismic stress monitoring is proposed in this paper. The proposed SA consists of a piece of PZT (lead zirconate titanate) patch sandwiched between a pair of marble cubes through epoxy. A soft PZT is selected, rendering the SA as a potential actuator in active sensing. Finite element analysis (FEA) was conducted to investigate the stress distribution in the SA under compression, which is used for calculating its sensitivity to compressive stresses. With a commercially available charge amplifier, the frequency response of both the amplitude and the phase shift of the sensing system are investigated by applying the frequency sweep loading scheme on the proposed SA. The frequency ranges from 0.01 to 10 Hz, corresponding to the range of seismic frequency response of most building structures. The alternating load for evaluating SA sensitivity was applied by the servo-hydraulic machine. The lower limit of frequency response is determined to be 0.5 Hz. The depolarization process of the piezoelectric coefficient of the selected PZT material was investigated to decide the load-holding time in calibration tests. The degradation of the piezoelectric coefficient with a series of compressive pre-stresses from 4.8 to 24 MPa was evaluated, and the experimental results showed that the influence from the considered range of pre-stresses is negligible. Using a commercially available charge amplifier, the proposed SA-based sensing system can monitor the seismic stress of low- and middle-rise building structures under moderate earthquakes.

  16. Development of dual PZT transducers for reference-free crack detection in thin plate structures.

    PubMed

    Sohn, Hoon; Kim, Seuno Bum

    2010-01-01

    A new Lamb-wave-based nondestructive testing (NDT) technique, which does not rely on previously stored baseline data, is developed for crack monitoring in plate structures. Commonly, the presence of damage is identified by comparing "current data" measured from a potentially damaged stage of a structure with "baseline data" previously obtained at the intact condition of the structure. In practice, structural defects typically take place long after collection of the baseline data, and the baseline data can be also affected by external loading, temperature variations, and changing boundary conditions. To eliminate the dependence on the baseline data comparison, the authors previously developed a reference-free NDT technique using 2 pairs of collocated lead zirconate titanate (PZT) transducers placed on both sides of a plate. This reference-free technique is further advanced in the present study by the necessity of attaching transducers only on a single surface of a structure for certain applications such as aircraft. To achieve this goal, a new design of PZT transducers called dual PZT transducers is proposed. Crack formation creates Lamb wave mode conversion due to a sudden thickness change of the structure. This crack appearance is instantly detected from the measured Lamb wave signals using the dual PZT transducers. This study also suggests a reference-free statistical approach that enables damage classification using only the currently measured data set. Numerical simulations and experiments were conducted using an aluminum plate with uniform thickness and fundamental Lamb waves modes to demonstrate the applicability of the proposed technique to reference-free crack detection. PMID:20040449

  17. Investigations on structural and multiferroic properties of artificially engineered lead zirconate titanate-cobalt iron oxide layered nanostructures

    NASA Astrophysics Data System (ADS)

    Ortega Achury, Nora Patricia

    Mutiferroics are a novel class of next generation multifunctional materials, which display simultaneous magnetic, electric, and ferroelastic ordering, have drawn increasing interest due to their multi-functionality for a variety of device applications. Since, very rare single phase materials exist in nature this kind of properties, an intensive research activity is being pursued towards the development of new engineered materials with strong magneto-electric (ME) coupling. In the present investigation, we have fabricated polycrystalline and highly oriented PbZr0.53,Ti0.47O3--CoFe 2O4 (PZT/CFO) artificially multilayers (MLs) engineered nanostructures thin films which were grown on Pt/TiO2/SiO2/Si and La 0.5Sr0.5CoO3 (LSCO) coated (001) MgO substrates respectively, using the pulsed laser deposition technique. The effect of various PZT/CFO sandwich configurations having 3, 5, and 9 layers, while maintaining similar total PZT and CFO thickness, has been systematically investigated. The first part of this thesis is devoted to the analysis of structural and microstructure properties of the PZT/CFO MLs. X-ray diffraction (XRD) and micro Raman analysis revealed that PZT and CFO were in the perovskite and spinel phases respectively in the all layered nanostructure, without any intermediate phase. The TEM and STEM line scan of the ML thin films showed that the layered structure was maintained with little inter-diffusion near the interfaces at nano-metric scale without any impurity phase, however better interface was observed in highly oriented films. Second part of this dissertation was dedicated to study of the dielectric, impedance, modulus, and conductivity spectroscopies. These measurements were carried out over a wide range of temperatures (100 K to 600 K) and frequencies (100 Hz to 1 MHz) to investigate the grain and grain boundary effects on electrical properties of MLs. The temperature dependent dielectric and loss tangent illustrated step-like behavior and

  18. The Physics of Sol-Gel Derived Ferroelectric Thin Film PZT

    NASA Astrophysics Data System (ADS)

    Melnick, Bradley Michael

    Initial examination of a simple Auger depth profile reveals that thin film, pure lead zirconate titanate (PZT) is intrinsically a layered structure. Oxygen vacancies at the electrode interfaces create an n-type region in a normally p-type material by contributing electrons into the conduction band. Therefore, such measurable effects as the polarization versus applied field (hysteresis), and the dielectric constant versus applied field are all thickness dependent via a space charge effect on the surface of the material. M. E. Lines has suggested that the decay in switching polarization (fatigue) of barium titanate is linked to a build up of a space charge layer near the surface region. Although no specifics as to the source of the space charge layer (electronic or ionic) are given, it is implied that the space charge layer does inhibit switching due to an interaction with the domain nuclei. Therefore, it is plausible that degradation of the remnant polarization in PZT may also be connected with a surface layer. The implication from the above discussion is that thin film ferroelectric materials, such as sol-gel derived PZT, are intrinsically layered structures. This thesis involves the study of ferroelectric PZT synthesized via a solution-gelation technique (sol -gel). Using a reproducible and stable liquid solution, thin films are made by spinning droplets of the metalorganic liquid onto a substrate. The thin layers are then dried and annealed in order to form perovskite phase ferroelectric PZT capacitors for testing. A testing methodology is presented in order to test the capacitors unambiguous of artifacts due to the integration process. Capacitance versus voltage (CV), true DC leakage current, switching curve and hysteresis curve data is analyzed in order to examine the unique properties of the thin film ferroelectric. CV analysis indicates that a depletion region exists near the surface of the ferroelectric capacitor. The depletion region is found to dominate

  19. Effect of buffer layer on the voltage responsivity of the pyroelectric thermal sensors prepared with PZT ceramics

    NASA Astrophysics Data System (ADS)

    Lee, Moon-Ho; Hwang, Ha R.; Bae, Seong-Ho

    1997-08-01

    The pyroelectric thermal detectors were prepared with lead zirconate titanate (PZT) ceramics, where a signal electrode had a structure of Au/metallic buffer/(PZT ceramic). The effect of buffer layer on the voltage responsivity was investigated with a response to step signal, taken by dynamic pyroelectric measurement. Pyroelectric ceramic wafer was prepared by mixed oxide technique. Au layer (thickness: 50 nm) and metallic buffers (thickness: 0 - 20 nm) of Cr, NiCr (80/20), and Ti were prepared by dc magnetron sputtering. In order to improve the light absorptivity, an Au-black was coated on Au signal electrode by thermal evaporation. At steady state, the output voltage (Vo) was decreased with increasing chopping frequency in the range of 1 - 100 Hz. A sensor without buffer showed the severe time-drift and instability in the output signal. However, the sensors with buffer layer showed the stable outputs. For step radiations, rising time (tp), peak voltage (Vp), and initial slope (k) of the output voltage were dependent upon the thickness and materials of buffer layer. The mechanical and electrical contacts between Au electrode and PZT ceramics were improved by inserting the metallic buffer layer. Considering the characteristics of the output voltage, the optimum thickness of buffer layer was about 15 - 20 nm, and the sensors with Ti buffer of 15 - 20 nm in thickness showed the good detectivity. Therefore, the stability and reliability of the thermal sensors could be improved by use of appropriate buffer layer.

  20. Enhancing the dielectric property of 0.69PZT-0.31PZNN thick films by optimizing the poling condition

    NASA Astrophysics Data System (ADS)

    Song, Daniel; Woo, Min Sik; Ahn, Jung Hwan; Sung, Tae Hyun

    2015-05-01

    We investigated how the applied electric-field's magnitude and the poling time affected, respectively, the dielectric property and the microstructure of piezoelectric lead zirconate titanate/lead zirconate nickel niobate (PZT-PZNN) thick films in order to apply the films to piezoelectric energy harvesters. Several 300-µm-thick, 10 × 10-mm2 PZT-PZNN squares were tape cast, laminated, sintered, and poled under 2-, 4-, 6-, 10-, 14-, and 15-kV/mm electric fields for 30 min. The 10-kV/mm electric field produced the highest d 33 × g 33 without mechanically damaging the sample. Further, samples were sintered at 950, 1000, and 1020 °C and subsequently poled at 10 kV/mm (previously determined as the magnitude of the optimal poling electric field) for 15, 30, 60, 120, and 240 min to investigate how the poling time affected the piezoelectric ceramic's microstructure. The optimal poling time for all the sintered samples was 60 min. Further, the piezoelectric ceramics composed of small grains and poled longer than 60 min showed higher dielectric constants. However, those composed of large grains and poled for times shorter than 60 min showed higher dielectric constants because the element mobility of the piezoelectric ceramics increased with increasing poling time.

  1. Synthesis of lead zirconate titanate nanofibres and the Fourier-transform infrared characterization of their metallo-organic decomposition process

    NASA Astrophysics Data System (ADS)

    Wang, Yu; Santiago-Avilés, Jorge J.

    2004-01-01

    We have synthesized Pb(Zr0.52Ti0.48)O3 fibres with diameters ranging from 500 nm to several microns using electrospinning and metallo-organic decomposition techniques (Wang et al 2002 Mater. Res. Soc. Symp. Proc. 702 359). By a refinement of our electrospinning technique, i.e. by increasing the viscosity of the precursor solution, and by adding a filter to the tip of the syringe, the diameter of the synthesized PZT fibres has been reduced to the neighbourhood of 100 nm. The complex thermal decomposition was characterized using Fourier-transform infrared (FTIR) spectroscopy and x-ray diffraction (XRD). It was found that alcohol evaporated during electrospinning and that most of the organic groups had pyrolysed before the intermediate pyrochlore phase was formed. There is a good correspondence between XRD and FTIR spectra. We also verify that a thin film of platinum coated on the silicon substrate catalyses the phase transformation of the pyrochlore into the perovskite phase.

  2. High-precision impedance spectroscopy: a strategy demonstrated on PZT.

    PubMed

    Boukamp, Bernard A; Blank, Dave H A

    2011-12-01

    Electrochemical impedance spectroscopy (EIS) has been recognized as a very powerful tool for studying charge and mass transport and transfer in a wide variety of electrically or electrochemically active systems. Sophisticated modeling programs make it possible to extract parameters from the impedance data, thus contributing to a better understanding of the system or material properties. For an accurate analysis, a correct modeling function is needed; this is often in the form of an equivalent circuit. It is not always possible to define the modeling function from visual inspection of the impedance dispersion. Small contributions to the overall dispersion can be masked, and hence overlooked. In this publication, a strategy is presented for high-precision impedance data analysis. A Kramers-Kronig test is used for the essential data validation. An iterative process of partial analysis and subtraction assists in deconvoluting the impedance spectrum, yielding both a vi- able model function and a set of necessary starting values for the full complex nonlinear least squares (CNLS) modeling. The advantage and possibilities of this strategy are demonstrated with an analysis of the ionic and electronic conductivity of lead zirconate titanate (PZT) as functions of temperature and oxygen partial pressure. PMID:23443688

  3. Emission, plasma formation, and brightness of a PZT ferroelectric cathode

    SciTech Connect

    Sampayan, S.; Caporaso, G.; Trimble, D.; Westenskow, G.

    1995-04-27

    We have measured an 36-A-cm{sup {minus}2} current emission density over the surface area of an 11.4-cm{sup 2}-area Lead-Titanate- Zirconate (PZT) ferroelectric cathode with a pulsed anode-cathode (A-K) potential of 50 kV. We have also observed currents above those predicted by classical Child-Langmuir formula for a wide variety of cases. Since a plasma within the A-K gap could also lead to increase current emission we are attempting to measure the properties of the plasma near the cathode surface at emission time. In other measurements, we have observed strong gap currents in the absence of an A-K potential. Further, we continue to make brightness measurements of the emitted beam and observe spatially non-uniform emission and large shot-to-shot variation. Measurements show individual beamlets with a brightness as high 10{sup 11} Am{sup {minus}2} rad{sup {minus}2}.

  4. Fatigue Response of a PZT Multilayer Actuator under High-Field Electric Cycling with Mechanical Preload

    SciTech Connect

    Wang, Hong; Wereszczak, Andrew A; Lin, Hua-Tay

    2009-01-01

    An electric fatigue test system has been developed for piezoelectric actuator with a mechanical loading capability. Fatigue responses of a lead zirconate titanate (PZT) multilayer actuator (MLA) with a plate-through electrode configuration have been studied under an electric field (1.7 times that of a coercive field of PZT material) and a concurrent mechanical preload (30.0 MPa). A total of 1.0x10^9 cycles were carried out. Variations in charge density and mechanical strain under a high electric field and constant mechanical loads were observed during the fatigue test. The dc and the first harmonic (at 10 Hz) dielectric and piezoelectric coefficients were subsequently characterized by using FFT (Fast Fourier Transformation). It has been observed that both the dielectric and the piezoelectric coefficients underwent a monotonic decrease prior to 2.86x10^8 cycles under the relevant preload, and then fluctuated to a certain extent. Both the dielectric loss tangent and the piezoelectric loss tangent also exhibited the fluctuations after a certain amount of drop but at different levels relative to the pre-fatigue. And finally, the results were discussed with respect to domain wall mobility, microcracking, and other pre-existing anomalies.

  5. Optimized pyroelectric properties of 0-3 composites of PZT particles in polyurethane doped with lithium perchlorate.

    PubMed

    Ploss, Bernd; Krause, Markus

    2007-12-01

    A substantial improvement in the performance of pyroelectric 0-3 composites of ceramic particles in a polymer matrix has been achieved by doping the polymer matrix material. Readily prepared and polarized films with various volume fractions of lead zirconate-titanate (PZT) particles in polyurethane have been doped in a solution of lithium perchlorate in acetone to increase the conductivity. With an appropriate conductivity, the dielectric permittivities of the ceramic particles and the polymer matrix become matched, resulting in an improvement of the pyroelectric coefficient from about 6 microC/(m(2)K) to about 50 microC/(m(2)K). The experimental results are explained by theoretical predictions. PMID:18276541

  6. Optical amplification in disordered electrooptic Tm{sup 3+} and Ho{sup 3+} codoped lanthanum-modified lead zirconate titanate ceramics and study of spectroscopy and communication between cations

    SciTech Connect

    Zhao, Hua; Zhang, Kun; Xu, Long; Sun, Fankui; Zhang, Jingwen; Chen, Xuesheng; Li, Kewen K.

    2014-02-21

    Rare earth doped electro-optic (EO) ceramics of lanthanum-modified lead zirconate titanate (PLZT) are promising in building multifunctional optical devices, by taking advantage of both EO effect and optical activity. In this work, the combination of the measured spectra of absorption and photoluminescence, the fluorescent decay, the calculated Judd-Ofelt parameters, and measured single pass gain in Tm{sup 3+}, Ho{sup 3+} codoped PLZT ceramics have marked them out as promising gain media in building electrically controllable lasers/optical amplifiers and other multifunctional devices. Optical energy storage was also observed in the optical amplification dynamics.

  7. Clamping effect on the piezoelectric responses of screen-printed low temperature PZT/Polymer films on flexible substrates

    NASA Astrophysics Data System (ADS)

    Almusallam, A.; Yang, K.; Zhu, D.; Torah, R. N.; Komolafe, A.; Tudor, J.; Beeby, S. P.

    2015-11-01

    This paper introduces a new flexible lead zirconate titanate (PZT)/polymer composite material that can be screen-printed onto fabrics and flexible substrates, and investigates the clamping effect of these substrates on the characterization of the piezoelectric material. Experimental results showed that the optimum blend of PZT/polymer binder with a weight ratio of 12:1 provides a dielectric constant of 146. The measured value of the piezoelectric coefficient d33 was found to depend on the substrate used. Measured d33clp values of 70, 40, 36 pC N-1 were obtained from the optimum formulation printed on Polyester-cotton with an interface layer, Kapton and alumina substrates, respectively. The variation in the measured d33clp values occurs because of the effect of the mechanical boundary conditions of the substrate. The piezoelectric film is mechanically bonded to the surface of the substrate and this constrains the film in the plane of the substrate (the 1-direction). This constraint means that the perpendicular forces (applied in the 3-direction) used to measure d33 introduce a strain in the 1-direction that produces a charge of the opposite polarity to that induced by the d33 effect. This is due to the negative sign of the d31 coefficient and has the effect of reducing the measured d33 value. Theoretical and experimental investigations confirm a reduction of 13%, 50% and 55% in the estimated freestanding d33fs values (80 pC N-1) on Polyester-cotton, Kapton and alumina substrates, respectively. These results demonstrate the effect of the boundary conditions of the substrate/PZT interface on the piezoelectric response of the PZT/polymer film and in particular the reduced effect of fabric substrates due to their lowered stiffness.

  8. Ion-beam sputtering deposition and magnetoelectric properties of layered heterostructures (FM/PZT/FM)n, where FM - Co or Ni78Fe22

    NASA Astrophysics Data System (ADS)

    Stognij, Alexander; Novitskii, Nikolai; Sazanovich, Andrei; Poddubnaya, Nadezhda; Sharko, Sergei; Mikhailov, Vladimir; Nizhankovski, Viktor; Dyakonov, Vladimir; Szymczak, Henryk

    2013-08-01

    Magnetoelectric properties of layered heterostructures (FM/PZT/FM)n (n≤ 3) obtained by ion-beam sputtering deposition of ferromagnetic metal (FM), where FM is the cobalt (Co) or permalloy Ni78Fe22, onto ferroelectric ceramic based on lead zirconate titanate (PZT) have been studied. The polished ferroelectric plates in thickness from 400 to 20 μm were subjected to finished treatment by ion-beam sputtering. After plasma activation they were covered by the ferromagnetic films from 1 to 6 μm in thickness. Enhanced characteristics of these structures were reached by means of both the thickness optimization of ferroelectric and ferromagnetic layers and obtaining of ferromagnetic/ferroelectric interfaces being free from defects and foreign impurities. Assuming on the basis of analysis of elastic stresses in the ferromagnetic film that the magnetoelectric effect forms within ferromagnetic/ferroelectric interface, the structures with 2-3 ferromagnetic layers were obtained. In layered heterostructure (Py/PZT/Py)3, the optimal thickness of ferromagnetic film was 2 μm, and outer and inner ferroelectric layers had 20 μm and 80 μm in thickness, respectively. For such structure the maximal magnetoelectric voltage coefficient of 250 mV/(cm Oe) was reached at a frequency 100 Hz in magnetic field of 0.25 T at room temperature. The structures studied can serve as energy-independent elements detecting the change of magnetic or electric fields in electronic devices based on magnetoelectric effect.

  9. Real-Time, Label-Free, All-Electrical Detection of Salmonella typhimurium Using Lead Zirconate Titanate/Gold-Coated Glass Cantilevers at any Relative Humidity

    PubMed Central

    Zhu, Qing; Shih, Wan Y.; Shih, Wei-Heng

    2007-01-01

    We have examined non-insulated PZT/gold-coated glass cantilevers for real-time, label-free detection of Salmonella t. by partial dipping at any relative humidity. The PZT/gold-coated glass cantilevers were consisted of a 0.127 mm thick PZT layer about 0.8 mm long, 2 mm wide bonded to a 0.15 mm thick gold-coated glass layer with a 3.0 mm long gold-coated glass tip for detection. We showed that by placing the water level at the nodal point, about 0.8 mm from the free end of the gold-glass tip, there was a 1-hr window in which the resonance frequency was stable despite the water level change by evaporation at 20% relative humidity or higher. By dipping the cantilevers to their nodal point, we were able to do real-time, label-free detection without background resonance frequency corrections at any relative humidity. The partially dipped PZT/gold-coated glass cantilever exhibited mass detection sensitivity, Δm/Δf = −5×10−11g/Hz, and a detection concentration sensitivity, 5×103 cells/ml in 2 ml of liquid, which was about two orders of magnitude lower than that of a 5 MHz QCM. It was also about two orders of magnitude lower than the infection dosage and one order of magnitude lower that the detection limit of a commercial Raptor sensor. PMID:22872784

  10. The effect of a hydrostatic pressure on the D-E response of Nb modified 95/5 PZT

    NASA Astrophysics Data System (ADS)

    Lynch, Christopher; Valadez, Carlos; Altgilbers, Larry; Sahul, Raffi; Alberta, Ed; Hackenberger, Wes

    2012-02-01

    Niobium doped lead zirconate titanate (95/5 NbPZT) undergoes a hydrostatic pressure induced FE to AFE phase transformation. This work reports the large field dielectric response to both unipolar and bipolar electric field as 95/5 PZT passes through the forward and reverse FE-AFE transformations. The poled ceramic was first hydrostatically depoled by driving the FE-AFE phase transformation and stress-strain and stress - electric displacement responses were measured. Next, specimens were subjected to electric field loading at different hydrostatic pressure levels. Electric field was varied at a series of fixed pressure levels between zero and 550 MPa. The unipolar experiments resulted in minor hysteresis loops with the area inside the loops dependent on both pressure and electric field amplitude. Two different slopes were taken from the D-E loops, identified as the small field and large field slopes. Each changed with pressure and displayed distinct jumps at the forward and reverse FE-AFE phase transformations. The area within the loops in the ferroelectric regime, attributed to domain wall motion, increased as pressure was increased and dropped abruptly as the material passed through the pressure induced phase transformation. The bipolar experiments resulted in open D-E hysteresis loops in the ferroelectric phase that transitioned to linear in the anti-ferroelectric phase.

  11. Damage Detection Based on Power Dissipation Measured with PZT Sensors through the Combination of Electro-Mechanical Impedances and Guided Waves.

    PubMed

    Sevillano, Enrique; Sun, Rui; Perera, Ricardo

    2016-01-01

    The use of piezoelectric ceramic transducers (such as Lead-Zirconate-Titanate-PZT) has become more and more widespread for Structural Health Monitoring (SHM) applications. Among all the techniques that are based on this smart sensing solution, guided waves and electro-mechanical impedance techniques have found wider acceptance, and so more studies and experimental works can be found containing these applications. However, even though these two techniques can be considered as complementary to each other, little work can be found focused on the combination of them in order to define a new and integrated damage detection procedure. In this work, this combination of techniques has been studied by proposing a new integrated damage indicator based on Electro-Mechanical Power Dissipation (EMPD). The applicability of this proposed technique has been tested through different experimental tests, with both lab-scale and real-scale structures. PMID:27164104

  12. Detection of cancer biomarkers by piezoelectric biosensor using PZT ceramic resonator as the transducer.

    PubMed

    Su, Li; Zou, Lan; Fong, Chi-Chun; Wong, Wing-Leung; Wei, Fan; Wong, Kwok-Yin; Wu, Rudolf S S; Yang, Mengsu

    2013-08-15

    A novel piezoelectric biosensor using lead titanate zirconate (PZT) ceramic resonator as transducer was developed for label-free, cost-effective, and direct detection of cancer biomarkers. We designed a dual sensing scheme where two ceramic resonators were connected in parallel, in which one resonator was used as the sensing unit and the other as the control unit, in order to minimize environment influences including temperature fluctuation and to achieve the required frequency stability for biosensing applications. Detection of selected cancer biomarkers, such as prostate specific antigen (PSA) and α-fetoprotein (AFP) was carried out to evaluate the performance of the biosensor. The device showed high sensitivity (0.25 ng/ml) and fast detection (within 30 min) with small amount of sample (1 μl), which is compatible to that required by clinical measurements. The results also showed that the ceramic resonator-based piezoelectric biosensor platform could be utilized with different chemical interfaces, and the miniaturized size of the ceramic resonators makes it suitable for fabricating sensor arrays for multiplex detection. PMID:23542085

  13. Out-of-Plane Translational PZT Bimorph Actuator with Archimedes’ Spiral Actuating Tethers

    NASA Astrophysics Data System (ADS)

    Yang, Chenye; Liu, Sanwei; Livermore, Carol

    2015-12-01

    The design, finite element analysis (FEA), and experimental characterization of a MEMS out-of-plane (vertical) translational lead-zirconate-titanate (PZT) bimorph actuator supported on Archimedes’ spiral tethers are presented. Two types of bimorph actuators with different electrode patterns (with spiral tethers half actuated or fully actuated) are designed and fabricated. Both designs are fabricated by commercial processes and are compatible with integration into more complex MEMS systems. Finite element analysis (FEA) was used to analyze and predict the displacements of both types of actuators. The deflections of both fully- actuated and half-actuated devices were measured experimentally to validate the design. At an applied voltage of 110V, the out-of-plane deflections of the actuators with half-actuated and fully-actuated tethers were measured at about 17 μm and 29 μm respectively, in good agreement with FEA predictions of 17.1 μm and 25.8 μm. The corresponding blocking forces are predicted as 10 mN and 17 mN by FEA.

  14. An investigation of vibration-induced protein desorption mechanism using a micromachined membrane and PZT plate.

    PubMed

    Yeh, Po Ying; Le, Yevgeniya; Kizhakkedathu, Jayachandran N; Chiao, Mu

    2008-10-01

    A micromachined vibrating membrane is used to remove adsorbed proteins on a surface. A lead zirconate titanate (PZT) composite (3 x 1 x 0.5 mm) is attached to a silicon membrane (2,000 x 500 x 3 microm) and vibrates in a flexural plate wave (FPW) mode with wavelength of 4,000/3 microm at a resonant frequency of 308 kHz. The surface charge on the membrane and fluid shear stress contribute in minimizing the protein adsorption on the SiO(2) surface. In vitro characterization shows that 57 +/- 10% of the adsorbed bovine serum albumin (BSA), 47 +/- 13% of the immunoglobulin G (IgG), and 55.3~59.2 +/- 8% of the proteins from blood plasma are effectively removed from the vibrating surface. A simulation study of the vibration-frequency spectrum and vibrating amplitude distribution matches well with the experimental data. Potentially, a microelectromechanical system (MEMS)-based vibrating membrane could be the tool to minimize biofouling of in vivo MEMS devices. PMID:18427993

  15. Exploring the piezoelectric performance of PZT particulate-epoxy composites loaded in shear

    NASA Astrophysics Data System (ADS)

    Van Loock, F.; Deutz, D. B.; van der Zwaag, S.; Groen, W. A.

    2016-08-01

    The active and passive piezoelectric response of lead zirconium titanate (PZT)-epoxy particulate composites loaded in shear is studied using analytical models, a finite element model and by experiments. The response is compared to that of the same composites when loaded in simple tension. Analogously to bulk PZT, particulate PZT-polymer composites loaded in shear show higher piezoelectric charge coefficient (d 15) and energy density figure of merit (FOM15) values compared to simple tension (d 33) and (FOM33). This outcome demonstrates the as-yet barely explored potential of piezoelectric particulate composites for optimal strain energy harvesting when activated in shear.

  16. Identification of Material Properties of PZT Single Crystals through Crystallographic Homogenization Method

    NASA Astrophysics Data System (ADS)

    Uetsuji, Yasutomo; Tanaka, Satoshi; Tsuchiya, Kazuyoshi; Ueda, Sei; Nakamachi, Eiji

    Single crystals of lead zirconium titanate (PZT) are difficult to fabricate. Thus, not all material properties of PZT have been fully characterized. In this paper, the mechanical and electrical properties of a PZT single crystal, which can be assumed to be identical to those of a crystal grain in a polycrystal, have been computed from those of a polycrystalline PZT ceramic by the steepest decent method and multiscale finite element modeling based on crystallographic homogenization method. Crystallographic homogenization enables us to predict macroscopic properties of ceramics taking into account the inhomogeneous microstructure of an aggregate of crystal grains. The crystal morphology of the PZT ceramic was measured by the SEM·EBSD technique, and the result was used in the microscopic finite element model. Then, the mechanical and electrical properties of the crystal grain were derived by the steepest decent method so that its macroscopic properties would correspond to the measured properties of the PZT ceramic. The proposed computational method was applied to barium titanate (BT) and validated by comparison of the computed material properties with known properties of the BT single crystal. Finally, the computed material properties, such as the elastic compliance, and the dielectric and piezoelectric constants, were presented for the PZT single crystal.

  17. Optical tuning of electrical properties of PZT thin film deposited on STO

    NASA Astrophysics Data System (ADS)

    Gupta, Reema; Tomar, Monika; Gupta, Vinay

    2015-11-01

    Present report deals with the optical tuning of electrical properties of PZT thin film based photodetector (PD). Lead Zirconium Titanate (PZT) thin film has been fabricated over epitaxially matched Strontium Titanate (STO) substrate using Pulsed Laser Deposition technique. Fine aluminium inter digital electrodes were patterned over PZT film to study the response of the PD. The photo response has been investigated by tuning the optical properties of the incident laser beam. The response was found to be modified according to the incident laser intensity and the distance between sample and laser. Moreover, PZT based photo detector was found to be highly sensitive towards small variation in the optical properties of the incident light. The intrinsic properties of the PZT thin film including its ferroelectric properties make it a novel material for the fabrication of UV based photo detector. The response of the PZT based Photodetector was found to be about 152 at a distance of 10cm between the PD and the UV laser of wavelength 365nm. The response time and recovery time were found to be 60 msec each which are much faster for UV detection as compared to other photodetectors. Moreover, a stable response was also observed on the repetitive UV sensing for the fabricated PZT based Photodetector.

  18. The fabrication and material characterization of PZT based functionally graded piezoceramics

    NASA Astrophysics Data System (ADS)

    Alexander, Paul W.; Brei, Diann; Halloran, John W.

    2005-05-01

    Functionally Graded Piezoceramics (FGP) increase actuator lifetime and provide complex deformations; however, to reap these benefits sophisticated grading and fabrication techniques beyond the conventional layered bonding techniques are required. This paper introduces the Dual Electro/Piezo Property (DEPP) gradient technique via MicroFabrication through CoeXtrusion (MFCX). The Dual Electro/Piezo Property (DEPP) grading technique pairs a high displacement lead zirconate titanate (PZT) piezoceramic with a high permittivity barium titanate (BT) dielectric. These compatible materials act synergistically to form dramatic gradients in permittivity across the structure, concentrating the electric field in the more piezoelectrically active region leading to electrically-efficient, large-displacement actuators; with the benefit of increased reliability stemming from the continuous gradients and monolithic nature of the ceramic. The DEPP variation was first evaluated independently of the MFCX process through fabrication and experimental characterization of a powder pressed bimorph. While simple one-dimensionally graded FGPs can be realized by this process, MFCX is needed for any complex, multidimensional gradient. The MFCX process was adapted for DEPP grading and demonstrated by creating a more complex linearly-graded FGP. Both the bimorph and linearly graded specimens had good material quality and generated high displacements correlating well with published FGP theory; with the linear gradient reducing internal stress levels, extending actuator lifetime. This paper presents a general FGP methodology that couples grading and fabrication to generate high yield, low cost monolithic actuators with complicated one-dimensional gradients. Extension of this research will pave the way for more complicated gradients yielding such deformation capabilities as warping, twisting, rippling, and dimpling.

  19. In-Situ phase and texture characterization of solution deposited PZT thin films during crystallization.

    SciTech Connect

    Brennecka, Geoffrey L.; Nittala, Krishna; Jones, Jacob L.

    2010-08-01

    Ferroelectric lead zirconate titanate (PZT) thin films are used for integrated capacitors, ferroelectric memory, and piezoelectric actuators. Solution deposition is routinely used to fabricate these thin films. During the solution deposition process, the precursor solutions are spin coated onto the substrate and then pyrolyzed to form an amorphous film. The amorphous film is then heated at a higher temperature (650-700 C) to crystallize the film into the desired perovskite phase. Phase purity is critical in achieving high ferroelectric properties. Moreover, due to the anisotropy in the structure and properties of PZT, it is desirable to control the texture obtained in these thin films. The heating rate during crystallization process is known to affect the sequence of phase evolution and texture obtained in these thin films. However, to date, a comprehensive understanding of how phase and texture evolution takes place is still lacking. To understand the effects of heating rate on phase and texture evolution, in-situ diffraction experiments during the crystallization of solution deposited PZT thin films were carried out at beamline 6-ID-B, Advanced Photon Source (APS). The high X-ray flux coupled with the sophisticated detectors available at the APS synchrotron source allow for in-situ characterization of phase and texture evolution at the high ramp rates that are commonly used during processing of PZT thin films. A PZT solution of nominal composition 52/48 (Zr/Ti) was spin coated onto a platinum-coated Si substrate (Pt//TiO{sub x}//SiO{sub 2}//Si). The films were crystallized using an infrared lamp, similar to a rapid thermal annealing furnace. The ramp rate was adjusted by controlling the voltage applied to the infrared lamp and increasing the voltage by a constant step with every acquisition. Four different ramp rates, ranging from {approx}1000 C/s to {approx}1 C/s, were investigated. The sample was aligned in grazing incidence to maximize the signal from the thin

  20. Magnetoelectric effect in layered ferrite/PZT composites. Study of the demagnetizing effect on the magnetoelectric behavior

    NASA Astrophysics Data System (ADS)

    Loyau, V.; Morin, V.; Chaplier, G.; LoBue, M.; Mazaleyrat, F.

    2015-05-01

    We report the use of high magnetomechanical coupling ferrites in magnetoelectric (ME) layered composites. Bilayer samples combining (Ni0.973 Co0.027)1-xZnxFe2O4 ferrites (x = 0-0.5) synthesized by non conventional reactive Spark Plasma Sintering and commercial lead zirconate titanate (PZT) were characterized in term of ME voltage coefficients measured at sub-resonant frequency. Strong ME effects are obtained and we show that an annealing at 1000 °C and a quenching in air improve the piezomagnetic behavior of Zn-rich compositions. A theoretical model that predicts the ME behavior was developed, focusing our work on the demagnetizing effects in the transversal mode as well as the longitudinal mode. The model shows that: (i) high ME coefficients are obtained when ferrites with high magnetomechanical coupling are used in bilayer ME composites, (ii) the ME behavior in transversal and longitudinal modes is quite similar, and differences in the shapes of the ME curves are mainly due the demagnetizing effects, (iii) in the transversal mode, the magnetic field penetration depends on the ferrite layer thickness and the ME coefficient is affected accordingly. The two later points are confirmed by measurements on ME samples and calculations. Performances of the ME composites made with high magnetomechanical coupling ferrites are compared to those obtained using Terfenol-D materials in the same conditions of size, shape, and volume ratio. It appears that a ferrite with an optimized composition has performances comparable to those obtained with Terfenol-D material. Nevertheless, the fabrication processes of ferrites are quite simpler. Finally, a ferrite/PZT based ME composite was used as a current sensor.

  1. A three-degree-of-freedom thin-film PZT-actuated microactuator with large out-of-plane displacement

    PubMed Central

    Choi, Jongsoo; Qiu, Zhen; Rhee, Choong-Ho; Wang, Thomas; Oldham, Kenn

    2014-01-01

    A novel three degree-of-freedom microactuator based on thin-film lead-zirconate-titanate (PZT) is described with its detailed structural model. Its central rectangular-shaped mirror platform, also referred to as the stage, is actuated by four symmetric PZT bending legs such that each leg provides vertical translation for one corner of the stage. It has been developed to support real-time in vivo vertical cross-sectional imaging with a dual axes confocal endomicroscope for early cancer detection, having large displacements in three axes (z, θx, θy) and a relatively high bandwidth in the z-axis direction. Prototype microactuators closely meet the performance requirements for this application; in the out-of-plane (z-axis) direction, it has shown more than 177 μm of displacement and about 84 Hz of structural natural frequency, when two diagonal legs are actuated at 14V. With all four legs, another prototype of the same design with lighter stage mass has achieved more than 430 μm of out-of-plane displacement at 15V and about 200 Hz of bandwidth. The former design has shown approximately 6.4° and 2.9° of stage tilting about the x-axis and y-axis, respectively, at 14V. This paper also presents a modeling technique that uses experimental data to account for the effects of fabrication uncertainties in residual stress and structural dimensions. The presented model predicts the static motion of the stage within an average absolute error of 14.6 μm, which approaches the desired imaging resolution, 5 μm, and also reasonably anticipates the structural dynamic behavior of the stage. The refined model will support development of a future trajectory tracking controller for the system. PMID:25506131

  2. A three-degree-of-freedom thin-film PZT-actuated microactuator with large out-of-plane displacement

    NASA Astrophysics Data System (ADS)

    Choi, Jongsoo; Qiu, Zhen; Rhee, Choong-Ho; Wang, Thomas; Oldham, Kenn

    2014-07-01

    A novel three degree-of-freedom microactuator based on thin-film lead-zirconate-titanate (PZT) is described with its detailed structural model. Its central rectangular-shaped mirror platform, also referred to as the stage, is actuated by four symmetric PZT bending legs such that each leg provides vertical translation for one corner of the stage. It has been developed to support real-time in vivo vertical cross-sectional imaging with a dual axes confocal endomicroscope for early cancer detection, having large displacements in three axes (z, θx, θy) and a relatively high bandwidth in the z-axis direction. Prototype microactuators closely meet the performance requirements for this application; in the out-of-plane (z-axis) direction, it has shown more than 177 μm of displacement and about 84 Hz of structural natural frequency, when two diagonal legs are actuated at 14V. With all four legs, another prototype of the same design with lighter stage mass has achieved more than 430 μm of out-of-plane displacement at 15V and about 200 Hz of bandwidth. The former design has shown approximately 6.4° and 2.9° of stage tilting about the x-axis and y-axis, respectively, at 14V. This paper also presents a modeling technique that uses experimental data to account for the effects of fabrication uncertainties in residual stress and structural dimensions. The presented model predicts the static motion of the stage within an average absolute error of 14.6 μm, which approaches the desired imaging resolution, 5 μm, and also reasonably anticipates the structural dynamic behavior of the stage. The refined model will support development of a future trajectory tracking controller for the system.

  3. A large-scan-angle piezoelectric MEMS optical scanner actuated by a Nb-doped PZT thin film

    NASA Astrophysics Data System (ADS)

    Naono, Takayuki; Fujii, Takamichi; Esashi, Masayoshi; Tanaka, Shuji

    2014-01-01

    Resonant 1D microelectromechanical systems (MEMS) optical scanners actuated by piezoelectric unimorph actuators with a Nb-doped lead zirconate titanate (PNZT) thin film were developed for endoscopic optical coherence tomography (OCT) application. The MEMS scanners were designed as the resonance frequency was less than 125 Hz to obtain enough pixels per frame in OCT images. The device size was within 3.4 mm × 2.5 mm, which is compact enough to be installed in a side-imaging probe with 4 mm inner diameter. The fabrication process started with a silicon-on-insulator wafer, followed by PNZT deposition by the Rf sputtering and Si bulk micromachining process. The fabricated MEMS scanners showed maximum optical scan angles of 146° at 90 Hz, 148° at 124 Hz, 162° at 180 Hz, and 152° at 394 Hz at resonance in atmospheric pressure. Such wide scan angles were obtained by a drive voltage below 1.3 Vpp, ensuring intrinsic safety in in vivo uses. The scanner with the unpoled PNZT film showed three times as large a scan angle as that with a poled PZT films. A swept-source OCT system was constructed using the fabricated MEMS scanner, and cross-sectional images of a fingertip with image widths of 4.6 and 2.3 mm were acquired. In addition, a PNZT-based angle sensor was studied for feedback operation.

  4. High performance Au/PZT/TiOxNy/Si MFIS structure for next generation ferroelectric memory applications

    NASA Astrophysics Data System (ADS)

    Sharma, Deepak K.; Khosla, Robin; Sharma, Satinder K.

    2015-05-01

    The Metal-Ferroelectric-Insulator-Semiconductor (MFIS) capacitors with thin 20 nm lead zirconate titanate (PZT) and titanium oxynitride (TiOxNy) buffer layer were fabricated by RF magnetron sputtering technique and characterized. TiOxNy as a buffer layer deposited for the first time for MFIS application at different thicknesses and fabricated structure was found to exhibit excellent electrical characteristics at 14 nm TiOxNy. Memory window of 0.4 V was found at low sweep voltage of ± 3 V which increases to 1.8 V at sweep voltage of ±14 V indicating multilevel data storage. Moreover the fabricated structure possesses low leakage current density of ˜4 µA/cm2 at 36 nm TiOxNy which increases to 12 µA/cm2 at 4 nm TiOxNy at 5 V, reasonable limit. Furthermore, the fabricated structure possesses outstanding data retention capability at 14 nm TiOxNy; the high and low capacitance becomes constant after few seconds and clearly distinguishable for 1h and 30 min. This shows that proposed MFIS structure is suitable for high performance ferroelectric memory applications.

  5. Chem-prep PZT 95/5 for neutron generator applicatios : powder preparation characterization utilizing design of experiments.

    SciTech Connect

    Lockwood, Steven John; Rodman-Gonzales, Emily Diane; Voigt, James A.; Moore, Diana Lynn

    2003-07-01

    Niobium doped PZT 95/5 (lead zirconate-lead titanate) is the material used in voltage bars for all ferroelectric neutron generator power supplies. In June of 1999, the transfer and scale-up of the Sandia Process from Department 1846 to Department 14192 was initiated. The laboratory-scale process of 1.6 kg has been successfully scaled to a production batch quantity of 10 kg. This report documents efforts to characterize and optimize the production-scale process utilizing Design of Experiments methodology. Of the 34 factors identified in the powder preparation sub-process, 11 were initially selected for the screening design. Additional experiments and safety analysis subsequently reduced the screening design to six factors. Three of the six factors (Milling Time, Media Size, and Pyrolysis Air Flow) were identified as statistically significant for one or more responses and were further investigated through a full factorial interaction design. Analysis of the interaction design resulted in developing models for Powder Bulk Density, Powder Tap Density, and +20 Mesh Fraction. Subsequent batches validated the models. The initial baseline powder preparation conditions were modified, resulting in improved powder yield by significantly reducing the +20 mesh waste fraction. Response variation analysis indicated additional investigation of the powder preparation sub-process steps was necessary to identify and reduce the sources of variation to further optimize the process.

  6. Dynamic Electromechanical Characterization of Axially Poled PZT 95/5

    SciTech Connect

    Chhabildas, Lalit C.; Furnish, Michael D.; Montgomery, Stephen T.; Setchell, Robert E.

    1999-06-25

    We are conducting a comprehensive experimental study of the electromechanical behavior of poled PZT 95/5 (lead zirconate titattate). As part of this study, eight plane-wave tests have been conducted on axially poled PZT 95/5 at stress levels ranging from 0.9 to 4.6 GPa, using VISAR and electrical diagnos- tics. Observed wave velocities were slightly decreased from ultrasonic vahtes, by contrast' with unpoled samples. Compression waveforms show a step at 0.6 GPa more marked than for normally poled or unpoled samples; this may correspond to a poling effect on the ferroelectric/antiferroelectric transition. A similar step is observed on release. The released charge upon loading to 0.9 GPa is consistent with nearly complete depoling. Loading to higher stresses gave lower currents (factor of 10), suggesting shock-induced conduc- tivity or electrical breakdown.

  7. New Candidate for FRAM Dielectric Layer—Rare Earth Europium Doped PZT Thin Films

    NASA Astrophysics Data System (ADS)

    Yu, Y. J.; Li, Y. M.; Chan, H. L. W.

    2005-03-01

    Europium (Eu) doped lead zirconium titanate (PZT) ferroelectric thin films (PEZT) were grown on platinized Si substrates by a sol-gel technique with a rapid thermal process. Based on the analysis of TEM and AFM, an obvious modification of PZT films by Eu doping was observed. Compared with undoped PZT, PEZT films show 5 times larger size of grains (100 nm) but only 15% increase in roughness mean square (about 1.08 nm). That is, PEZT films with high quality (large grain size and good uniformity) were fabricated under the same processing condition as pure PZT, in no charge of long-time and high-temperature. The high quality PEZT dielectric layer could greatly improve the performance, mainly the reliability and the reproducibility of FRAM units. Furthermore, increased remenant polarization and improved polarization fatigue properties were found by optimizing Eu doping content. Mechanism of Eu doping effects on the microstructure and electrical properties of PZT films was discussed from the physics of crystal growth and the defect chemistry points of view.

  8. Biologically functionalized nanochannels on ferroelectric lead zirconium titanate surfaces.

    SciTech Connect

    Ocola, L. E.; Pan, W. C.; Kuo, M.; Tirumala, V. R.; Reiss, B. D.; Firestone, M. A.; Illinois Mathematics and Science Academy

    2005-01-01

    We recently started a program at Argonne to exploit patterned, polarizable ferroelectric surfaces, such as lead zirconium titanate (PZT), as a means to create field-responsive inorganic-biomolecule interfaces to study and manipulate biomatter on surfaces. In this paper we will discuss the integration of nanochannels on the surface of PZT films and their selective functionalization to create nanovalves to control nanofluidic flow. Microfluidic devices have been fabricated using a variety of methods, ranging from thermal decomposition of buried patterned channels, to fabricating trenches via plasma etch or hot embossing followed by trench capping. Our work focuses on an alternative method by using a bilayer resist in an inverted configuration normally used for T- and Gamma- gate fabrication. This method is capable of yielding sub-100 nm nanochannels with high aspect ratios and sub-500nm alignment. We have recently demonstrated that the polarization hysteresis loop of PZT is the same before and after exposure to an aqueous environment. This opens the possibility of selective surface modification of PZT via coupling of a wide range of biomolecules (e.g., peptides, proteins) and the use of the electric-field-responsive properties of PZT to manipulate the function (e.g., orientation) of the tethered biomolecules. We have used phage display techniques to evolve specific peptide motifs that selectively bind to PZT. The optimum heptapeptide that facilitates both the attachment of functional biological molecules to the surface of PZT has been identified.

  9. Control of crystallographic texture and surface morphology of Pt/Tio2 templates for enhanced PZT thin film texture.

    PubMed

    Fox, Austin J; Drawl, Bill; Fox, Glen R; Gibbons, Brady J; Trolier-McKinstry, Susan

    2015-01-01

    Optimized processing conditions for Pt/TiO2/SiO2/Si templating electrodes were investigated. These electrodes are used to obtain [111] textured thin film lead zirconate titanate (Pb[ZrxTi1-x ]O3 0 ≤ x ≤ 1) (PZT). Titanium deposited by dc magnetron sputtering yields [0001] texture on a thermally oxidized Si wafer. It was found that by optimizing deposition time, pressure, power, and the chamber pre-conditioning, the Ti texture could be maximized while maintaining low surface roughness. When oxidized, titanium yields [100]-oriented rutile. This seed layer has as low as a 4.6% lattice mismatch with [111] Pt; thus, it is possible to achieve strongly oriented [111] Pt. The quality of the orientation and surface roughness of the TiO2 and the Ti directly affect the achievable Pt texture and surface morphology. A transition between optimal crystallographic texture and the smoothest templating surface occurs at approximately 30 nm of original Ti thickness (45 nm TiO2). This corresponds to 0.5 nm (2 nm for TiO2) rms roughness as determined by atomic force microscopy and a full-width at half-maximum (FWHM) of the rocking curve 0002 (200) peak of 5.5/spl degrees/ (3.1/spl degrees/ for TiO2). A Pb[Zr0.52Ti 0.48]O3 layer was deposited and shown to template from the textured Pt electrode, with a maximum [111] Lotgering factor of 87% and a minimum 111 FWHM of 2.4/spl degrees/ at approximately 30 nm of original Ti. PMID:25585390

  10. Explosive crystallization of PZT microstructures by femtosecond infrared radiation

    NASA Astrophysics Data System (ADS)

    Elshin, A. S.; Firsova, N. Yu; Emelianov, V. I.; Pronin, I. P.; Senkevich, S. V.; Zhigalina, O. M.; Mishina, E. D.; Sigov, A. S.

    2015-12-01

    The features of microstructure crystallization into perovskite phase in lead zirconate titanate film by femtosecond laser radiation of near-infrared range were discussed. In-situ crystallization kinetics by method of second harmonic generation (SHG) was studied. The presence of several types of crystallization was shown, including ultra-fast (explosive) crystallization occurring immediately after the start of exposure, and slow (self-sustaining) crystallization, occurring after termination of exposure. The advantage of the second-harmonic generation microscopy for the study of annealed microstructures was shown. The morphology of microstructures was investigated by transmission electron microscopy (TEM).

  11. Structural Properties of Ferroelectric Lead(Zirconium0.5,Titanium0.5)Oxygen3 Nanotube Array and Electronic Structure of Lao delta-doped strontium titanate

    NASA Astrophysics Data System (ADS)

    Adhikari, Rajendra P.

    In this Dissertation we begin with two introductions on: 1) ferroelectricity and related phenomena, and 2) novel properties of Oxide electronics and the generation of two dimensional electron gas. We then give theoretical background of density functional theory (including LDA+U) and pseudopotentials. The first part of research work is about structural, polarization, and dielectric properties of ferroelectric Lead Zirconate Titanate (PZT) solid solution in the form of a nanotube array, embedded in a matrix medium of different ferroelectric strengths. We use the effective Hamiltonian derived from first-principles and finite-temperature Monte Carlo methods to determine the various properties. We revealed different polarization phases of the system in the absence of an external electric field and explained these properties in microscopic detail. In the second part, we study the effects of compressive biaxial inplane strains on the electronic and structural properties of Lanthanum Oxide delta-doped Strontium Titanate supercell. We use first-principles density functional calculations within the local density approximation including also on-site Coulomb interaction energy. We approached the problem by comparing the band structures, localization of electronic states, and cation-anion displacements of unstrained and strained systems. We found a critical strain above which there are abrupt changes in conduction band dispersions and cation-anion displacements, indicating that inplane biaxial strain can drastically tune the properties of this system, which may have potential technological applications.

  12. The effects of non-hydrostatic compression and applied electric field on the electromechanical behavior of poled PZT 95/5-2Nb ceramic during the F{sub R1} {yields} A{sub 0} polymorphic phase transformation

    SciTech Connect

    Zeuch, D.H.; Montgomery, S.T.; Zimmerer, D.J.

    1995-10-01

    We conducted hydrostatic and constant-stress-difference (CSD) experiments at room temperature on two different sintered batches of poled, niobium-doped lead-zirconate-titanate ceramic (PZT 95/5-2Nb). The objective of this test plan was to quantify the effects of nonhydrostatic stress on the electromechanical behavior of the ceramic during the ferroelectric, rhombohedral {yields} antiferroelectric, orthorhombic (FE {yields} AFE) phase transformation. We also performed a series of hydrostatic and triaxial compression experiments in which a 1000 V potential was applied to poled specimens to evaluate any effect of a sustained bias on the transformation. As we predicted from earlier tests on unpoled PZT 95/5-2Nb, increasing the stress difference up to 200 MPa (corresponding to a maximum resolved shear stress of 100 MPa) decreases the mean stress and confining pressure at which the transformation occurs by 25--33%, for both biased and unbiased conditions. This same stress difference also retards the rate of transformation at constant pressurization rate, resulting in reductions of up to an order of magnitude in the rate of charge release and peak voltage attained in our tests. This shear stress-voltage effect offers a plausible, though qualitative explanation for certain systematic failures that have occurred in neutron generator power supplies when seemingly minor design changes have been made. Transformation strains in poled ceramic are anisotropic (differing by up to 33%) in hydrostatic compression, and even more anisotropic under non-hydrostatic stress states. Application of a 1000 V bias appears to slightly increase (by {le}2%) the transformation pressure for poled ceramic, but evidence for this conclusion is weak.

  13. Studies on electrical properties and the magnetoelectric effect on ferroelectric-rich (x)Ni0.8Zn0.2Fe2O4+(1-x) PZT ME composites

    NASA Astrophysics Data System (ADS)

    Chougule, S. S.; Chougule, B. K.

    2007-04-01

    Magnetoelectric composites with ferrite-ferroelectric composition (x)Ni0.8Zn0.2Fe2O4+(1-x) PZT (lead zirconate titanate (PbZr0.52Ti0.48O3) used as a ferroelectric phase) in which x varies as 0, 0.15, 0.30, 0.45 and 1 mol% were prepared by using a conventional ceramic double-sintering method. Phase analysis was carried out using the x-ray diffraction technique, which confirms a cubic spinel structure for the ferrite and tetragonal perovskite structure for the ferroelectric phase. The variation of the dielectric constant (ɛ') and loss tangent (tanδ) in the frequency range 20 Hz-1 MHz were studied. The conduction phenomenon is explained on the basis of a small polaron hopping model. The confirmation of this phenomenon was made with the help of ac conductivity measurements. The dc resistivity was measured as a function of temperature in the range from room temperature to 800 °C. Hysteresis measurements were performed to determine the saturation magnetization (Ms) and magnetic moment (ηB). The static magnetoelectric conversion factor (dE/dH)H was measured as a function of the magnetic field. All composites show a linear decrease of magnetoelectric conversion in the presence of a static magnetic field.

  14. Comparison of Properties of Pt/PZT/Pt and Ru/PZT/Pt Ferroelectric Capacitors

    NASA Astrophysics Data System (ADS)

    Jia, Ze; Ren, Tian-Ling; Liu, Tian-Zhi; Hu, Hong; Zhang, Zhi-Gang; Xie, Dan; Liu, Li-Tian

    2006-04-01

    Pb(Zr0.4Ti0.6)O3 film prepared by sol-gel spin coating on a Pt/Ti/SiO2/Si substrate is applied to ferroelectric capacitors with Pt or Ru as the top electrode. For the Pt/PZT/Pt and Ru/PZT/Pt ferroelectric capacitors, although with the same ferroelectric film, different top electrode materials incur different properties of PZT capacitors, such as fatigue, leakage, remanent and saturated polarization, except the similar crystal orientations of the PZT film. After 1010 switch cycles, the remanent polarizations of the Ru/PZT/Pt and Pt/PZT/Pt capacitors decrease to 70% and 84%, respectively. The leakage current density of the latter increases obviously at positive bias after 108 switch cycles, compared with the former. Different materials for the top electrode bring different conditions at the PZT/top electrode interface. The influence of oxygen-vacancy concentration at the PZT/electrode interface and the influence of oxides of the electrode material at the PZT/electrode interface to charge injection can explain the difference of properties of the PZT capacitors with Pt or Ru as the top electrodes.

  15. A new PZT with prolonged exposure and Wuchang PZT catalogue.

    NASA Astrophysics Data System (ADS)

    Gao, Buxi; Li, Jingfeng; Hu, Yashe

    The most important improvement in the authors' PZT is that the stars with 11 mag. can be observed, because exposure time for dimmer stars is prolonged. The observational practice during last three years denotes that the method of prolonged exposure is very successful. The number of observed stars is increased about three times, and the precision is improved. As there are so many star images in the plate, a series of processes is suggested, which includes the process of predicting the positions of star images on plates, finding out the pairs of star images and their corresponding stars automatically, calculating the apparent positions of stars and giving the final observational results. The corrections of 289 stars (on 150 measured plates) are given. The results show that many errors of stellar positions in AGK 3R and AGK 3 are larger than 0″5.

  16. Polarization characterization of PZT disks and of embedded PZT plates by thermal wave methods

    SciTech Connect

    Eydam, Agnes Suchaneck, Gunnar Gerlach, Gerald; Esslinger, Sophia; Schönecker, Andreas; Neumeister, Peter

    2014-11-05

    In this work, the thermal wave method was applied to characterize PZT disks and embedded PZT plates with regard to the polarization magnitude and spatial homogeneity. The samples were exposed to periodic heating by means of a laser beam and the pyroelectric response was determined. Thermal relaxation times (single time constants or distributions of time constants) describe the heat losses of the PZT samples to the environment. The resulting pyroelectric current spectrum was fitted to the superposition of thermal relaxation processes. The pyroelectric coefficient gives insight in the polarization distribution. For PZT disks, the polarization distribution in the surface region showed a characteristic decrease towards the electrodes.

  17. Uniaxial Compression Experiments on Lead Zirconate Titanate 95/5-2Nb Ceramic: Evidence for an Orientation-Dependent, ''Maximum Compressive Stress'' Criterion for Onset of the Ferroelectric - Antiferroelectric Polymorphic Transformation

    SciTech Connect

    Zeuch, D.H.; Montgomery, S.T.; Holcomb, D.J.

    1999-07-26

    Some time ago we presented evidence that, under nonhydrostatic loading, the F{sub R1} {r_arrow} A{sub O} polymorphic transformation of unpoled PZT 95/5-2Nb (PNZT) ceramic began when the maximum compressive stress equaled the hydro-static pressure at which the transformation otherwise took place. Recently we showed that this simple criterion did not apply to nonhydrostatically compressed, poled ceramic. However, unpoled ceramic is isotropic, whereas poled ceramic has a preferred crystallographic orientation and is mechanically anisotropic. If we further assume that the transformation depends not only on the magnitude of the compressive stress, but also its orientation relative to some feature(s) of PNZT's crystallography, then these disparate results can be qualitatively resolved. It has long been known that this transformation can be triggered in uniaxial compression. Our modified hypothesis makes two predictions for transformation of unpoled polycrystals under uniaxial stress: (i) the transformation should begin when the maximum compressive stress, {sigma}{sub 1}, equals the hydrostatic pressure for transformation, and (ii) a steadily increasing axial stress should be required to drive the transformation.

  18. Zircon growth in slate

    NASA Astrophysics Data System (ADS)

    Dempster, T. J.; Hay, D. C.; Bluck, B. J.

    2004-03-01

    Clastic sedimentary and low-grade metasedimentary rocks preserve populations of detrital zircons because of the unreactive nature of this mineral. However, evidence of new zircon growth has been found within highly heterogeneous populations of zircon from several greenschist facies slates from the Scottish Highlands. Small (<10 μm), anhedral, unzoned zircons and discrete overgrowths on rounded detrital grains are very common. These new fine-grained zircons have crystallized at temperatures below 350 °C and have been observed only in polished thin sections; they are absent from conventional mineral separates. Typical separation techniques create severe biases in the heavy-mineral populations of metasedimentary rocks, and recognition of the growth of zircon in such conditions may allow isotopic dating of low-temperature events.

  19. Modified lead titanate thin films for pyroelectric infrared detectors on gold electrodes

    NASA Astrophysics Data System (ADS)

    Ahmed, Moinuddin; Butler, Donald P.

    2015-07-01

    Pyroelectric infrared detectors provide the advantage of both a wide spectral response and dynamic range, which also has enabled systems to be developed with reduced size, weight and power consumption. This paper demonstrates the deposition of lead zirconium titanate (PZT) and lead calcium titanate (PCT) thin films for uncooled pyroelectric detectors with the utilization of gold electrodes. The modified lead titanate thin films were deposited by pulsed laser deposition on gold electrodes. The PZT and PCT thins films deposited and annealed at temperatures of 650 °C and 550 °C respectively demonstrated the best pyroelectric performance in this work. The thin films displayed a pyroelectric effect that increased with temperature. Poling of the thin films was carried out for a fixed time periods and fixed dc bias voltages at elevated temperature in order to increase the pyroelectric coefficient by establishing a spontaneous polarization of the thin films. Poling caused the pyroelectric current to increase one order of magnitude.

  20. Methane Clouds on Titan

    NASA Astrophysics Data System (ADS)

    Griffith, Caitlin A.

    Following the Voyager encounter with Titan in 1981 Saturn's largest moon was hypothesized sport a liquid cycle similar that on Earth with clouds rain and seas. On Titan methane is the condensible playing the role that water plays on Earth. Although the presence of seas is difficult to establish from ground methane clouds have been detected on Titan. Ground-based observations reveal that Titan's clouds differ remarkedly from their terrestrial counterparts. Titan's clouds are sparse reside primarily at particular altitude and concentrate presently in the south pole. That Titan's clouds are exotic is not surprising. Titan receives ~100 times less sunlight than Earth to drive weather. In addition Titan's radiative time constant is 180 years large compared to the 3 month terrestrial value. With little power and sluggish conditions it is not clear how clouds form on Titan. This talk will compare Titan to Earth to explore the nature of clouds under Titan's foreign conditions.

  1. Ceramic with zircon coating

    NASA Technical Reports Server (NTRS)

    Wang, Hongyu (Inventor)

    2003-01-01

    An article comprises a silicon-containing substrate and a zircon coating. The article can comprise a silicon carbide/silicon (SiC/Si) substrate, a zircon (ZrSiO.sub.4) intermediate coating and an external environmental/thermal barrier coating.

  2. Radiation Effects in Zircon

    SciTech Connect

    Ewing, Rodney C.; Meldrum, Alkiviathes; Wang, L. M.; Weber, William J.; Corrales, Louis R.

    2003-12-11

    The widespread distribution of zircon in the continental crust, its tendency to concentrate trace elements, particularly lanthanides and actinides, its use in age-dating, and its resistance to chemical and physical degradation have made zircon the most important accessory mineral in geologic studies. Because zircon is highly refractory, it also has important industrial applications, including its use as a lining material in high-temperature furnaces. However, during the past decade, zircon has also been proposed for advanced technology applications, such as a durable material for the immobilization of plutonium or, when modified by ion-beam irradiation, as an optic waveguide material. In all of these applications, the change in properties as a function of increasing radiation dose is of critical importance. In this chapter, we summarize the state-of-knowledge on the radiation damage accumulation process in zircon.

  3. Very High Frequency (Beyond 100 MHz) PZT Kerfless Linear Arrays

    PubMed Central

    Wu, Da-Wei; Zhou, Qifa; Geng, Xuecang; Liu, Chang-Geng; Djuth, Frank; Shung, K. Kirk

    2010-01-01

    This paper presents the design, fabrication, and measurements of very high frequency kerfless linear arrays prepared from PZT film and PZT bulk material. A 12-µm PZT thick film fabricated from PZT-5H powder/solution composite and a piece of 15-µm PZT-5H sheet were used to fabricate 32-element kerfless high-frequency linear arrays with photolithography. The PZT thick film was prepared by spin-coating of PZT sol-gel composite solution. The thin PZT-5H sheet sample was prepared by lapping a PZT-5H ceramic with a precision lapping machine. The measured results of the 2 arrays were compared. The PZT film array had a center frequency of 120 MHz, a bandwidth of 60% with a parylene matching layer, and an insertion loss of 41 dB. The PZT ceramic sheet array was found to have a center frequency of 128 MHz with a poorer bandwidth (40% with a parylene matching layer) but a better sensitivity (28 dB insertion loss). PMID:19942516

  4. Chemical durability of zircon

    NASA Astrophysics Data System (ADS)

    Trocellier, Patrick; Delmas, Robert

    2001-07-01

    Zircon (ZrSiO 4) exhibits a strong structural affinity for uranium and thorium together with a very high chemical durability. This makes it a potential crystalline host matrix to immobilize actinides issued from separation of nuclear wastes. Irradiation induces amorphization of the crystalline structure (the metamictization process) and thus may decrease the chemical durability of the material. Leaching tests have been conducted on natural zircons from Brazil and Madagascar at 96°C for a period of 1 month, using deionized water. Leachates have been analysed by inductively coupled plasma mass spectrometry (ICP-MS) and UV-visible spectrophotometry. Zircon solid surfaces have been investigated by coupling scanning electron microscopy and X-ray microanalysis (SEM-EDX) with nuclear microprobe analysis ( μPIXE, μRBS and μERDA). From the mass balance between leachates and hydrated surfaces, the probable mechanisms of zircon aqueous alteration are presented and discussed.

  5. Epitaxial growth of lead zirconium titanate thin films on Ag buffered Si substrates using rf sputtering

    SciTech Connect

    Wang Chun; Laughlin, David E.; Kryder, Mark H.

    2007-04-23

    Epitaxial lead zirconium titanate (PZT) (001) thin films with a Pt bottom electrode were deposited by rf sputtering onto Si(001) single crystal substrates with a Ag buffer layer. Both PZT(20/80) and PZT(53/47) samples were shown to consist of a single perovskite phase and to have the (001) orientation. The orientation relationship was determined to be PZT(001)[110](parallel sign)Pt(001)[110](parallel sign)Ag(001)[110](parallel sign)Si(001)[110]. The microstructure of the multilayer was studied using transmission electron microscopy (TEM). The electron diffraction pattern confirmed the epitaxial relationship between each layer. The measured remanent polarization P{sub r} and coercive field E{sub c} of the PZT(20/80) thin film were 26 {mu}C/cm{sup 2} and 110 kV/cm, respectively. For PZT(53/47), P{sub r} was 10 {mu}C/cm{sup 2} and E{sub c} was 80 kV/cm.

  6. Titan Meteorology

    NASA Astrophysics Data System (ADS)

    Mitchell, Jonathan

    2012-04-01

    Titan’s methane clouds have received much attention since they were first discovered spectroscopically (Griffith et al. 1998). Titan's seasons evolve slowly, and there is growing evidence of a seasonal response in the regions of methane cloud formation (e.g. Rodriguez et al. 2009). A complete, three-dimensional view of Titan’s clouds is possible through the determination of cloud-top heights from Cassini images (e.g., Ádámkovics et al. 2010). Even though Titan’s surface is warmed by very little sunlight, we now know Titan’s methane clouds are convective, evolving through tens of kilometers of altitude on timescales of hours to days with dynamics similar to clouds that appear on Earth (Porco et al. 2005). Cassini ISS has also shown evidence of rain storms on Titan that produce surface accumulation of methane (Turtle et al. 2009). Most recently, Cassini has revealed a 1000-km-scale, arrow-shaped cloud at the equator followed by changes that appear to be evidence of surface precipitation (Turtle et al. 2011b). Individual convective towers simulated with high fidelity indicate that surface convergence of methane humidity and dynamic lifting are required to trigger deep, precipitating convection (e.g. Barth & Rafkin 2010). The global expanses of these cloud outbursts, the evidence for surface precipitation, and the requirement of dynamic convergence and lifting at the surface to trigger deep convection motivate an analysis of storm formation in the context of Titan’s global circulation. I will review our current understanding of Titan’s methane meteorology using Cassini and ground-based observations and, in particular, global circulation model simulations of Titan’s methane cycle. When compared with cloud observations, our simulations indicate an essential role for planetary-scale atmospheric waves in organizing convective storms on large scales (Mitchell et al. 2011). I will end with predictions of Titan’s weather during the upcoming northern

  7. Pyroelectric effect in layered magnetoelectric PZT/Ni-Zn ferrite composites

    NASA Astrophysics Data System (ADS)

    Solnyshkin, A. V.; Bogomolov, A. A.; Karpenkov, D. Yu.; Kislova, I. L.; Belov, A. N.

    2016-04-01

    The electric response of layered 2-2 connectivity magnetoelectric composites to the action of a modulated heat flow, which is detected by a dynamic method, is studied. The kinetics of the pyroelectric response of the composite material to a pulsed thermal action is calculated. The experimental results and calculation data suggest that a modulated heat action induces a signal due to both the pyroelectric and piezoelectric effects. The latter effect is caused by the mechanical interaction of the layers of lead zirconate titanate ceramic and nickel-zinc (Ni-Zn) ferrite.

  8. Lamb wave dispersion in a PZT/metal/PZT sandwich plate with imperfect interface

    NASA Astrophysics Data System (ADS)

    Kurt, Ilkay; Akbarov, Surkay D.; Sezer, Semih

    2016-07-01

    The Lamb wave dispersion in a PZT/Metal/PZT sandwich plate is investigated by employing the exact linear equations of electro-elastic waves in piezoelectric materials within the scope of the plane-strain state. It is assumed that at the interfaces between the piezoelectric face layers and metal core layer, shear-spring and normal-spring type imperfect conditions are satisfied. The degree of this imperfectness is estimated through the corresponding shear-spring and normal-spring type parameters which appear in the contact condition characterizing the transverse and normal displacements' discontinuity. The corresponding dispersion equation is derived, and as a result of the numerical solution to this equation, the dispersion curves are constructed for the first and second lowest modes in the cases where the material of the face layers is PZT and the material of the middle layer is Steel (St). Consequently, for the PZT/St/PZT sandwich plate, the study of the influence of the problem parameters such as the piezoelectric and dielectric constants, layer thickness ratios, non-dimensional shear-spring, and normal-spring type parameters, is carried out. In particular, it is established that the imperfectness of the contact between the layers of the plate causes a decrease in the values of the wave propagation velocity.

  9. Genetic Adaptive Control for PZT Actuators

    NASA Technical Reports Server (NTRS)

    Kim, Jeongwook; Stover, Shelley K.; Madisetti, Vijay K.

    1995-01-01

    A piezoelectric transducer (PZT) is capable of providing linear motion if controlled correctly and could provide a replacement for traditional heavy and large servo systems using motors. This paper focuses on a genetic model reference adaptive control technique (GMRAC) for a PZT which is moving a mirror where the goal is to keep the mirror velocity constant. Genetic Algorithms (GAs) are an integral part of the GMRAC technique acting as the search engine for an optimal PID controller. Two methods are suggested to control the actuator in this research. The first one is to change the PID parameters and the other is to add an additional reference input in the system. The simulation results of these two methods are compared. Simulated Annealing (SA) is also used to solve the problem. Simulation results of GAs and SA are compared after simulation. GAs show the best result according to the simulation results. The entire model is designed using the Mathworks' Simulink tool.

  10. Titanic: A Statistical Exploration.

    ERIC Educational Resources Information Center

    Takis, Sandra L.

    1999-01-01

    Uses the available data about the Titanic's passengers to interest students in exploring categorical data and the chi-square distribution. Describes activities incorporated into a statistics class and gives additional resources for collecting information about the Titanic. (ASK)