Power harvesting using PZT ceramics embedded in orthopedic implants.

Science.gov (United States)

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.

Study of pyroelectric activity of PZT/PVDF-HFP composite

Directory of Open Access Journals (Sweden)

Luiz Francisco Malmonge

2003-12-01

Full Text Available Flexible, free-standing piezo and pyroelectric composite with 0 to 3 connectivity was made up from Lead Zirconate Titanate (PZT powder and poly(vinylidene fluoride-hexafluoropropylene (PVDF-HFP copolymer. The pyroelectric and the piezoelectric longitudinal (d33 coefficients were measured. A 50/50 vol.% PZT/PVDF-HFP composite resulted in piezo and pyroelectric coefficients of d33 = 25.0 pC/N and p = 4.5 × 10-4 C/m²K at 70 °C, respectively. Analysis of the complex permittivity in a wide range of frequency was carried out indicating lower permittivity of the composite in comparison with a permittivity of the PZT ceramic. The low value of the permittivity gives a high pyroelectric figure of merit indicating that this material can be used to build a temperature sensor in spite of the lower pyroelectric coefficient compared with PZT.

Investigation of Top/bottom Electrode and Diffusion Barrier Layer for PZT thick film MEMS Sensors

DEFF Research Database (Denmark)

Pedersen, Thomas; Hindrichsen, Christian Carstensen; Lou-Møller, R.

2007-01-01

In this work screen printed piezoelectric Ferroperm PZ26 lead zirconate titanate (PZT) thick film is used for two MEMS devices. A test structure is used to investigate several aspects regarding bottom and top electrodes. 450 nm ZrO2 thin film is found to be an insufficient diffusion barrier layer...... for thick film PZT sintered at 850degC. E-beam evaporated Al and Pt is patterned on PZT with a lift-off process with a line width down to 3 mum. The roughness of the PZT is found to have a strong influence on the conductance of the top electrode....

Investigation of Top/Bottom electrode and Diffusion Barrier Layer for PZT Thick Film MEMS Sensors

DEFF Research Database (Denmark)

Hindrichsen, Christian Carstensen; Pedersen, Thomas; Thomsen, Erik Vilain

2008-01-01

Top and bottom electrodes for screen printed piezoelectric lead zirconate titanate, Pb(ZrxTi1 - x)O3 (PZT) thick film are investigated with respect to future MEMS devices. Down to 100 nm thick E-beam evaporated Al and Pt films are patterned as top electrodes on the PZT using a lift-off process...... with a line width down to 3 μ m. A 700 nm thick ZrO2 layer as insolating diffusion barrier layer is found to be insufficient as barrier layer for PZT on a silicon substrate sintered at 850°C. EDX shows diffusion of Si into the PZT layer....

Estimation for bolt fastening conditions of thin aluminum structure using PZT sensors

International Nuclear Information System (INIS)

Hong, Yong; Han, Byeong Hee; Kim, Byung Jin; Hong, Dong Pyo; Kim, Young Moon

2007-01-01

This work presents a study on PZT impedance-based method, it is one of the NDT(Non-Destructive Technique). We study about assessment of the square-structure health condition by impedance-based technique using PZT patches, associated with longitudinal wave propagation. Health conditions of the square-structure controlled by bolt fastening condition is adjusted by torque wrench. In order to estimate the damage condition numerically, we suggest the evaluation method of impedance peak frequency shift

Mems-based pzt/pzt bimorph thick film vibration energy harvester

DEFF Research Database (Denmark)

Xu, Ruichao; Lei, Anders; Dahl-Petersen, Christian

2011-01-01

We describe fabrication and characterization of a significantly improved version of a MEMS-based PZT/PZT thick film bimorph vibration energy harvester with an integrated silicon proof mass. The main advantage of bimorph vibration energy harvesters is that strain energy is not lost in mechanical...... support materials since only PZT is strained, and thus it has a potential for significantly higher output power. An improved process scheme for the energy harvester resulted in a robust fabrication process with a record high fabrication yield of 98.6%. Moreover, the robust fabrication process allowed...... a high pressure treatment of the screen printed PZT thick films prior to sintering, improving the PZT thick film performance and harvester power output reaches 37.1 μW at 1 g....

Comparison of the Thermal Degradation of Heavily Nb-Doped and Normal PZT Thin Films.

Science.gov (United States)

Yang, Jeong-Suong; Kang, YunSung; Kang, Inyoung; Lim, SeungMo; Shin, Seung-Joo; Lee, JungWon; Hur, Kang Heon

2017-03-01

The degradation of niobium-doped lead zirconate titanate (PZT) and two types of PZT thin films were investigated. Undoped PZT, two-step PZT, and heavily Nb-doped PZT (PNZT) around the morphotropic phase boundary were in situ deposited under optimum condition by RF-magnetron sputtering. All 2- [Formula: see text]-thick films had dense perovskite columnar grain structure and self-polarized (100) dominant orientation. PZT thin films were deposited on Pt/TiO x bottom electrode on Si wafer, and PNZT thin film was on Ir/TiW electrode with the help of orientation control. Sputtered PZT films formed on microelectromechanical system (MEMS) gyroscope and the degradation rates were compared at different temperatures. PNZT showed the best resistance to the thermal degradation, followed by two-step PZT. To clarify the effect of oxygen vacancies on the degradation of the film at high temperature, photoluminescence measurement was conducted, which confirmed that oxygen vacancy rate was the lowest in heavy PNZT. Nb-doping PZT thin films suppressed the oxygen deficit and made high imprint with self-polarization. This defect distribution and high internal field allowed PNZT thin film to make the piezoelectric sensors more stable and reliable at high temperature, such as reflow process of MEMS packaging.

Multiscale numerical study on ferroelectric nonlinear response of PZT thin films (Conference Presentation)

Science.gov (United States)

Wakabayashi, Hiroki; Uetsuji, Yasutomo; Tsuchiya, Kazuyoshi

2017-06-01

PZT thin films have excellent performance in deformation precision and response speed, so it is used widely for actuators and sensors of Micro Electro Mechanical System (MEMS). Although PZT thin films outputs large piezoelectricity at morphotropic phase bounfary (MPB), it shows a complicated hysteresis behavior caused by domain switching and structural phase transition between tetragonal and rhombohedral. In general, PZT thin films have some characteristic crystal morphologies. Additionally mechanical strains occur by lattice mismatch with substrate. Therefore it is important for fabrication and performance improvement of PZT thin films to understand the relation between macroscopic hysteresis response and microstructural changes. In this study, a multiscale nonlinear finite element simulation was proposed for PZT thin films at morphotropic phase boundary (MPB) on the substrate. The homogenization theory was employed for scale-bridging between macrostructure and microstructure. Figure 1 shows the proposed multiscale nonlinear simulation [1-3] based on the homogenization theory. Macrostructure is a homogeneous structure to catch the whole behaviors of actuators and sensors. And microstructure is a periodic inhomogeneous structure consisting of domains and grains. Macrostructure and microstructure are connected perfectly by homogenization theory and are analyzed by finite element method. We utilized an incremental form of fundamental constitutive law in consideration with physical property change caused by domain switching and structural phase transition. The developed multiscale finite element method was applied to PZT thin films with lattice mismatch strain on the substrate, and the relation between the macroscopic hysteresis response and microscopic domain switching and structural phase transition were investigated. Especially, we discuss about the effect of crystal morphologies and lattice mismatch strain on hysteresis response.

Pb(Zr,TiO3 (PZT Thin Film Sensors for Fully-Integrated, Passive Telemetric Transponders

Directory of Open Access Journals (Sweden)

Richard X. FU

2011-04-01

Full Text Available The great potential of taking advantages of PZT in a single chip to achieve inexpensive, fully-integrated, passive telemetric transponders has been shown in this paper. The processes for the sputter deposition of Pb(Zr,TiO3 (PZT thin films from two different composite targets on both Si and c-plane sapphire substrates have been demonstrated. PZT thin films have been deposited by sputter technique. PZT films were deposited onto substrates (Si [(100 Cz wafer] and c-plane sapphire (0001//Ti//Pt followed by sputter-deposited Pt top electrodes. X-ray diffraction results showed that both sputtered PZT films were textured along the [110] direction. The degree of preference for the [110] direction was greater on sapphire substrate where the intensity of that peak is seen to be larger compared to the intensity one Si substrate. TEM data revealed that both sputtered PZT films were polycrystalline in nature. Selected area diffraction (SAD pattern showed that the degree of disorientation between the crystallites was smaller on sapphire substrate compared to on Si substrate, which confirmed the results from the XRD. The remnant polarization Pr on sapphire substrate was larger than on Si’s. The leakage current for the 11 % Pb target sputtered film was much less than 22 % Pb target sputtered film. The breakdown voltage on sapphire substrate was the best. However, for the 11 % Pb target sputtered film’s breakdown voltage was much higher than 22 % Pb target sputtered film.

Screen printed PZT/PZT thick film bimorph MEMS cantilever device for vibration energy harvesting

DEFF Research Database (Denmark)

Xu, Ruichao; Lei, Anders; Dahl-Petersen, Christian

2012-01-01

We present a microelectromechanical system (MEMS) based PZT/PZT thick film bimorph vibration energy harvester with an integrated silicon proof mass. Most piezoelectric energy harvesting devices use a cantilever beam of a non piezoelectric material as support beneath or in-between the piezoelectric...... elements. We show experimental results from two types PZT/PZT harvesting devices, one where the Pb(ZrxTi1−x)O3 (PZT) thick films are high pressure treated during the fabrication and the other where the treatment is omitted. We find that with the high pressure treatment prior to PZT sintering, the films...

Load sensor

OpenAIRE

Van den Ende, D.; Almeida, P.M.R.; Dingemans, T.J.; Van der Zwaag, S.

2007-01-01

The invention relates to a load sensor comprising a polymer matrix and a piezo-ceramic material such as PZT, em not bedded in the polymer matrix, which together form a compos not ite, wherein the polymer matrix is a liquid crystalline resin, and wherein the piezo-ceramic material is a PZT powder forming 30-60% by volume of the composite, and wherein the PZT powder forms 40-50% by volume of the composite.

Enhanced ferroelectric and piezoelectric properties in La-modified PZT ceramics

Science.gov (United States)

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.

Parametric and Wavelet Analyses of Acoustic Emission Signals for the Identification of Failure Modes in CFRP Composites Using PZT and PVDF Sensors

Energy Technology Data Exchange (ETDEWEB)

Prasopchaichana, Kritsada; Kwon, Oh Yang [Inha University, Incheon (Korea, Republic of)

2007-12-15

Combination of the parametric and the wavelet analyses of acoustic emission (AE) signals was applied to identify the failure modes in carbon fiber reinforced plastic (CFRP) composite laminates during tensile testing. AE signals detected by surface mounted lead-zirconate-titanate (PZT) and polyvinylidene fluoride (PVDF) sensors were analyzed by parametric analysis based on the time of occurrence which classifies AE signals corresponding to failure modes. The frequency band level-energy analysis can distinguish the dominant frequency band for each failure mode. It was observed that the same type of failure mechanism produced signals with different characteristics depending on the stacking sequences and the type of sensors. This indicates that the proposed method can identify the failure modes of the signals if the stacking sequences and the sensors used are known

Load sensor

NARCIS (Netherlands)

Van den Ende, D.; Almeida, P.M.R.; Dingemans, T.J.; Van der Zwaag, S.

2007-01-01

The invention relates to a load sensor comprising a polymer matrix and a piezo-ceramic material such as PZT, em not bedded in the polymer matrix, which together form a compos not ite, wherein the polymer matrix is a liquid crystalline resin, and wherein the piezo-ceramic material is a PZT powder

Fabrication and characterization of MEMS-based PZT/PZT bimorph thick film vibration energy harvesters

DEFF Research Database (Denmark)

Xu, Ruichao; Lei, Anders; Dahl-Petersen, Christian

2012-01-01

We describe the fabrication and characterization of a significantly improved version of a microelectromechanical system-based PZT/PZT thick film bimorph vibration energy harvester with an integrated silicon proof mass; the harvester is fabricated in a fully monolithic process. The main advantage...... yield of 98%. The robust fabrication process allowed a high pressure treatment of the screen printed PZT thick films prior to sintering. The high pressure treatment improved the PZT thick film performance and increased the harvester power output to 37.1 μW at 1 g root mean square acceleration. We also...... characterize the harvester performance when only one of the PZT layers is used while the other is left open or short circuit....

Experimental Investigation on Admittance-Based Piezoelectric Sensor Diagnostic Process

Energy Technology Data Exchange (ETDEWEB)

Jo, Hyejin; Park, Tongil; Park, Gyuhae [Chonnam National University, Gwangju (Korea, Republic of)

2015-01-15

Structural health monitoring (SHM) techniques based on the use of active-sensing piezoelectric (PZT) materials have received considerable attention. The validation of the PZT functionality during SHM operation is critical to successfully implementing a reliable SHM system. In this study, we investigated several parameters that affect the admittance-based sensor diagnostic process. We experimentally identified the temperature dependency of the active-sensor diagnostic process. We found that the admittance-based sensor diagnostic process can differentiate the adhesion conditions of bonding materials that are used to install a PZT on a structure, which is important when designing a sensor diagnostic process for an SHM system.

Design Considerations for Aural Vital Signs Using PZT Piezoelectric Ceramics Sensor Based on the Computerization Method

Directory of Open Access Journals (Sweden)

Jerapong Tantrakoon

2007-11-01

Full Text Available The purpose was to illustrate how system developed for measurement of the aural vital signs such as patient’s heart and lung sounds in the hospital. For heart sounds measurement must operate the frequency response between 20 – 800 Hz, and lung sounds measurement must operate the frequency response between 160 – 4,000 Hz. The method was designed PZT piezoelectric ceramics for both frequency response in the same PZT sensor. It converts a signal from aural vital sign form to voltage signal. The signal is suitably amplified and re-filtered in band pass frequency band. It is converted to digital signal by an analog to digital conversion circuitry developed for the purpose. The results were that all signals can fed to personal computer through the sound card port. With the supporting software for drawing of graphic on the screen, the signal for a specific duration is accessed and stored in the computer’s memory in term of each patient’s data. In conclusion, the data of each patient call dot pcg (.pcg for drawing graph and dot wave (.wave for sound listening or automatic sending via electronic mail to the physician for later analysis of interpreting the sounds on the basis of their time domain and frequency domain representation to diagnose heart disorders.

On the use of non-MPB lead zirconium titanate (PZT) granules for piezoelectric ceramic–polymer sensorial composites

NARCIS (Netherlands)

Shaji Karapuzha, A.; Kunnamkuzhakkal James, N.; van der Zwaag, S.; Groen, W.A.

2016-01-01

Modern flexible and sensitive sensors based on polymer–ceramic composites employ lead zirconate titanate (PZT) granulates having the morphotropic phase boundary (MPB) composition as the piezo active ingredient, as this composition gives the best properties in fully ceramic piezoelectric sensors.

On the use of non-MPB lead zirconium titanate (PZT) granules for piezoelectric ceramic–polymer sensorial composites

NARCIS (Netherlands)

Shaji Karapuzha, A.; Zwaag, S. van der; Groen, W.A.

2016-01-01

Modern flexible and sensitive sensors based on polymer–ceramic composites employ lead zirconate titanate (PZT) granulates having the morphotropic phase boundary (MPB) composition as the piezo active ingredient, as this composition gives the best properties in fully ceramic piezoelectric sensors. In

Enhanced pyroelectric and piezoelectric properties of PZT with aligned porosity for energy harvesting applications.

Science.gov (United States)

Zhang, Yan; Xie, Mengying; Roscow, James; Bao, Yinxiang; Zhou, Kechao; Zhang, Dou; Bowen, Chris R

2017-04-14

This paper demonstrates the significant benefits of exploiting highly aligned porosity in piezoelectric and pyroelectric materials for improved energy harvesting performance. Porous lead zirconate (PZT) ceramics with aligned pore channels and varying fractions of porosity were manufactured in a water-based suspension using freeze-casting. The aligned porous PZT ceramics were characterized in detail for both piezoelectric and pyroelectric properties and their energy harvesting performance figures of merit were assessed parallel and perpendicular to the freezing direction. As a result of the introduction of porosity into the ceramic microstructure, high piezoelectric and pyroelectric harvesting figures of merits were achieved for porous freeze-cast PZT compared to dense PZT due to the reduced permittivity and volume specific heat capacity. Experimental results were compared to parallel and series analytical models with good agreement and the PZT with porosity aligned parallel to the freezing direction exhibited the highest piezoelectric and pyroelectric harvesting response; this was a result of the enhanced interconnectivity of the ferroelectric material along the poling direction and reduced fraction of unpoled material that leads to a higher polarization. A complete thermal energy harvesting system, composed of a parallel-aligned PZT harvester element and an AC/DC converter, was successfully demonstrated by charging a storage capacitor. The maximum energy density generated by the 60 vol% porous parallel-connected PZT when subjected to thermal oscillations was 1653 μJ cm -3 , which was 374% higher than that of the dense PZT with an energy density of 446 μJ cm -3 . The results are beneficial for the design and manufacture of high performance porous pyroelectric and piezoelectric materials in devices for energy harvesting and sensor applications.

Temperature Dependent Electrical Properties of PZT Wafer

Science.gov (United States)

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.

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

International Nuclear Information System (INIS)

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

2014-01-01

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

Biotemplated synthesis of PZT nanowires.

Science.gov (United States)

Cung, Kellye; Han, Booyeon J; Nguyen, Thanh D; Mao, Sheng; Yeh, Yao-Wen; Xu, Shiyou; Naik, Rajesh R; Poirier, Gerald; Yao, Nan; Purohit, Prashant K; McAlpine, Michael C

2013-01-01

Piezoelectric nanowires are an important class of smart materials for next-generation applications including energy harvesting, robotic actuation, and bioMEMS. Lead zirconate titanate (PZT), in particular, has attracted significant attention, owing to its superior electromechanical conversion performance. Yet, the ability to synthesize crystalline PZT nanowires with well-controlled properties remains a challenge. Applications of common nanosynthesis methods to PZT are hampered by issues such as slow kinetics, lack of suitable catalysts, and harsh reaction conditions. Here we report a versatile biomimetic method, in which biotemplates are used to define PZT nanostructures, allowing for rational control over composition and crystallinity. Specifically, stoichiometric PZT nanowires were synthesized using both polysaccharide (alginate) and bacteriophage templates. The wires possessed measured piezoelectric constants of up to 132 pm/V after poling, among the highest reported for PZT nanomaterials. Further, integrated devices can generate up to 0.820 μW/cm(2) of power. These results suggest that biotemplated piezoelectric nanowires are attractive candidates for stimuli-responsive nanosensors, adaptive nanoactuators, and nanoscale energy harvesters.

Piezoelectric Sensor to Measure Soft and Hard Stiffness with High Sensitivity for Ultrasonic Transducers

Directory of Open Access Journals (Sweden)

Yan-Rui Li

2015-06-01

Full Text Available During dental sinus lift surgery, it is important to monitor the thickness of the remaining maxilla to avoid perforating the sinus membrane. Therefore, a sensor should be integrated into ultrasonic dental tools to prevent undesirable damage. This paper presents a piezoelectric (PZT sensor installed in an ultrasonic transducer to measure the stiffness of high and low materials. Four design types using three PZT ring materials and a split PZT for actuator and sensor ring materials were studied. Three sensor locations were also examined. The voltage signals of the sensor and the displacement of the actuator were analyzed to distinguish the low and high stiffness. Using sensor type T1 made of the PZT-1 material and the front location A1 provided a high sensitivity of 2.47 Vm/kN. The experimental results demonstrated that our design can measure soft and hard stiffness.

Biotemplated Synthesis of PZT Nanowires

Science.gov (United States)

2013-11-25

electromechanical coupling coefficient , Y is the Young’s modulus, and Ri is intrinsic resistance. The PZT nanowire- based film is taken to have negligible...robotic actuation, and bioMEMS. Lead zirconate titanate ( PZT ), in particular, has attracted significant attention, owing to its superior...electromechanical conversion performance. Yet, the ability to synthesize crystalline PZT nanowires with reproducible and well-controlled properties remains a

Assessment of a new piezoelectric transducer sensor for noninvasive cardiorespiratory monitoring of newborn infants in the NICU.

Science.gov (United States)

Sato, Shinichi; Ishida-Nakajima, Wako; Ishida, Akira; Kawamura, Masanari; Miura, Shinobu; Ono, Kyoichi; Inagaki, Nobuya; Takada, Goro; Takahashi, Tsutomu

2010-01-01

Electrocardiogram (ECG) and impedance pneumography (IPG), the most widely used techniques for cardiorespiratory monitoring in the neonatal intensive care unit (NICU), have the disadvantage of causing skin damage when used for very premature newborn infants. To prevent skin damage, we designed a new piezoelectric transducer (PZT) sensor. To assess the potential of the PZT sensor for cardiorespiratory monitoring in the NICU. The PZT sensor was placed under a folded towel under a neonate to detect an acoustic cardiorespiratory signal, from which heart rate (HR) and breathing rate (BR) were calculated, together with simultaneous ECG/IPG recording for 1-9 days for long and brief (1-min) assessment. The brief assessment showed average correlation coefficients of 0.92 +/- 0.12 and 0.95 +/- 0.02 between instantaneous HRs/BRs detected by the PZT sensor and ECG/IPG in 27 and 11 neonates examined. During the long assessment, the HR detection rate by the PZT sensor was approximately 10% lower than that by ECG (82.6 +/- 12.9 vs. 91.8 +/- 4.1%; p = 0.001, n = 27), although comparable (90.3 +/- 4.1 vs. 92.5 +/- 3.4%, p = 0.081) in approximately 70% (18/27) of neonates examined; BR detection rate was comparable between the PZT sensor and IPG during relatively stable signal conditions (95.9 +/- 4.0 vs. 95.3 +/- 3.5%; p = 0.38, n = 11). The PZT sensor caused neither skin damage nor body movement increase in all neonates examined. The PZT sensor is noninvasive and does not cause skin irritation, and we believe it does provide a reliable, accurate cardiorespiratory monitoring tool for use in the NICU, although the issue of mechanical-ventilation noise remains to be solved. Copyright 2010 S. Karger AG, Basel.

Fatigue-free PZT-based nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Hwang, H J; Sando, M [Nat. Ind. Res. Inst., Nagoya (Japan); Tajima, K [Synergy Ceramics Lab., Fine Ceramics Research Association, Nagoya (Japan); Niihara, K [ISIR, Osaka Univ., Mihogaoka, Ibaraki (Japan)

1999-03-01

The goal of this study is to fabricate fatigue-free piezoelectrics-based nanocomposites. Lead zirconate titanate (PZT) and metallic platinum (Pt) were selected as a matrix and secondary phase dispersoid. Fine Pt particles were homogeneously dispersed in the PZT matrix. Fatigue properties of the unpoled PZT-based nanocomposite under electrical cyclic loading were investigated. The electrical-field-induced crack growth was monitored by an optical microscope, and it depended on the number of cycles the sample was subjected to. Resistance to fatigue was significantly enhanced in the nanocomposite. The excellent fatigue behavior of the PZT/Pt nanocomposites may result from the grain boundary strenghtening due to the interaction between the matrix and Pt particles. (orig.) 8 refs.

No linealidad en muestras cerámicas de PZT muy delgadas

Directory of Open Access Journals (Sweden)

de Frutos, J.

1999-10-01

Full Text Available The development of piezoelectric sensors for high frequency requires to work with very thin samples of material. At this thick nesses, the stress concentration produces strong perturbations in the materials, and the origin oF a non linear response, which depends field on working conditions. With the goal to advance in the knowledgement of this phenomenon, and by using Complex Impedance Spectroscopy, we have analysed the response of PZT ceramics with thickness of microns as a function of the applied and the amplitude of the analysis signal. These results allow to establish the base to the development of ultrasonic tunable sensors for high frequency.

El desarrollo de sensores piezoeléctricos de alta frecuencia, exige trabajar con muestras de material muy delgadas, del orden de micras. En estos espesores, las tensiones de trabajo causan fuertes perturbaciones en los materiales, provocando respuestas no lineales, sumamente dependientes de las condiciones de trabajo. Con el objetivo de avanzar en el conocimiento de este fenómeno, y haciendo uso de la técnica de Espectroscopia de Impedancia Compleja, hemos analizado la respuesta de muestras de PZT cerámico adelgazadas a espesores de micras, en función del campo aplicado y de la amplitud de la señal de análisis. El estudio de estos resultados, puede permitir sentar las bases para el desarrollo de sensores ultrasónicos de alta frecuencia sintonizables.

Ceramics like PZT-PMN

International Nuclear Information System (INIS)

Droescher, R.E.; Sousa, V.C.; Bergman, C.P.

2009-01-01

The goal of this work was to achieve piezoelectric ceramics referring to the system PZT-PMN Pb(Mg 1 / 3 Nb 2 / 3 Zr 0 , 52 Ti 0 , 48 )O 3 . Have been analysed ceramics like 0,65PZT-0,35PMN ((Pb(Mg 0 , 1167 Nb 0 , 2300 Zr 0 , 3380 Ti 0 , 3120 )O 3 ), 0,75PZT-0,25PMN ((Pb(Mg 0 , 083 Nb 0 . 1675 Zr 0 , 3900 Ti 0 , 3600 )O3) and the 0,85PZT-0,15PMN ((Pb(Mg 0,0500 Nb 0 , 1000 Zr 0 , 4420 Ti 0 , 4080 )O 3 ). The influence of the calcination and concentration of PZT on the lattice phases, microstructure and density was evaluated. Then, the method used was the mixed-oxide method, the samples were taken under different temperatures of calcination before the final sinterizing. The DRX and SEM techniques were used to identify the phases formed and analyse the microstructure, respectively. The main result revealed that, the better way is to realize three burns before the final sinterizing at 1200 o C/4 h . Like that, on obtain for sure the average lattice phases, like: perovskite, pyrochlore and PbO and also tend to densify the samples. (author)

Design and fabrication of aspherical bimorph PZT optics

CERN Document Server

Tseng, T C; Yeh, Z C; Perng, S Y; Wang, D J; Kuan, C K; Chen, J R; Chen, C T

2001-01-01

Bimorph piezoelectric optics with a third-order-polynomial surface is designed and a prototype is fabricated as active optics. Two pairs of silicon (Si) and lead zirconate titanate (PZT) piezoelectric ceramic are bonded as Si-PZT-PZT-Si together with a multi-electrode or thin film resistor coating used as the control electrode between Si and PZT and metallic films as grounding between the interface of PZT ceramics. A linear voltage is applied to the bimorph PZT optics by probing the control electrodes from a two-channel controllable power supplier. In doing so, the optics surface can achieve a desired third-order-polynomial surface. Reducing hysteresis and creep in bimorph PZT X-ray optics is the only feasible way by inserting an appropriate capacitor in series with bimorph PZT optics to significantly reduce both effects.

Crack identification for reinforced concrete using PZT based smart rebar active sensing diagnostic network

Science.gov (United States)

Song, N. N.; Wu, F.

2016-04-01

An active sensing diagnostic system using PZT based smart rebar for SHM of RC structure has been currently under investigation. Previous test results showed that the system could detect the de-bond of concrete from reinforcement, and the diagnostic signals were increased exponentially with the de-bonding size. Previous study also showed that the smart rebar could function well like regular reinforcement to undertake tension stresses. In this study, a smart rebar network has been used to detect the crack damage of concrete based on guided waves. Experimental test has been carried out for the study. In the test, concrete beams with 2 reinforcements have been built. 8 sets of PZT elements were mounted onto the reinforcement bars in an optimized way to form an active sensing diagnostic system. A 90 kHz 5-cycle Hanning-windowed tone burst was used as input. Multiple cracks have been generated on the concrete structures. Through the guided bulk waves propagating in the structures from actuators and sensors mounted from different bars, crack damage could be detected clearly. Cases for both single and multiple cracks were tested. Different crack depths from the surface and different crack numbers have been studied. Test result shows that the amplitude of sensor output signals is deceased linearly with a propagating crack, and is decreased exponentially with increased crack numbers. From the study, the active sensing diagnostic system using PZT based smart rebar network shows a promising way to provide concrete crack damage information through the "talk" among sensors.

Fabrication and properties of SmFe2-PZT magnetoelectric thin films

KAUST Repository

Giouroudi, Ioanna

2013-05-17

Magnetoelectric (ME) thin film composites are attracting a continually increasing interest due to their unique features and potential applications in multifunctional microdevices and integrated units such as sensors, actuators and energy harvesting modules. By combining piezoelectric and highly magnetostrictive thin films, the potentialities of these materials increase. In this paper we report the fabrication of SmFe2 and PZT thin films and the investigation of their properties. First of all, a ~ 400 nm thin SmFe film was deposited on top of Si/SiO2 substrate by magnetron sputter deposition. Afterwards, a 140 nm Pt bottom electrode was sputtered on top of the SmFe film forming a bottom electrode. Spin coating was employed for the deposition of the 150 nm thin PZT layer. A PZT solution with 10 %Pb excess was utilized for this fabrication step. Finally, circular Pt top electrodes were sputtered as top electrodes. This paper focuses on the microstructure of the individual films characterized by X-Ray diffractometer (XRD) and scanning electron microscopy (SEM). A piezoelectric evaluation system, aixPES, with TF2000E analyzer component was used for the electric hysteresis measurements of PZT thin films and a vibrating sample magnetometer (VSM) was employed for the magnetic characterization of the SmFe. The developed thin films and the fabricated double layer SmFe-PZT exhibit both good ferromagnetic and piezoelectric responses which predict a promising ME composite structure. The quantitative chemical composition of the samples was confirmed by energy dispersive spectroscopy (EDX). © (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

Fabrication and properties of SmFe2-PZT magnetoelectric thin films

KAUST Repository

Giouroudi, Ioanna; Alnassar, Mohammed; Kosel, Jü rgen

2013-01-01

Magnetoelectric (ME) thin film composites are attracting a continually increasing interest due to their unique features and potential applications in multifunctional microdevices and integrated units such as sensors, actuators and energy harvesting modules. By combining piezoelectric and highly magnetostrictive thin films, the potentialities of these materials increase. In this paper we report the fabrication of SmFe2 and PZT thin films and the investigation of their properties. First of all, a ~ 400 nm thin SmFe film was deposited on top of Si/SiO2 substrate by magnetron sputter deposition. Afterwards, a 140 nm Pt bottom electrode was sputtered on top of the SmFe film forming a bottom electrode. Spin coating was employed for the deposition of the 150 nm thin PZT layer. A PZT solution with 10 %Pb excess was utilized for this fabrication step. Finally, circular Pt top electrodes were sputtered as top electrodes. This paper focuses on the microstructure of the individual films characterized by X-Ray diffractometer (XRD) and scanning electron microscopy (SEM). A piezoelectric evaluation system, aixPES, with TF2000E analyzer component was used for the electric hysteresis measurements of PZT thin films and a vibrating sample magnetometer (VSM) was employed for the magnetic characterization of the SmFe. The developed thin films and the fabricated double layer SmFe-PZT exhibit both good ferromagnetic and piezoelectric responses which predict a promising ME composite structure. The quantitative chemical composition of the samples was confirmed by energy dispersive spectroscopy (EDX). © (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

The effects of embedded piezoelectric fiber composite sensors on the structural integrity of glass-fiber–epoxy composite laminate

International Nuclear Information System (INIS)

Konka, Hari P; Wahab, M A; Lian, K

2012-01-01

Piezoelectric fiber composite sensors (PFCSs) made from micro-sized lead zirconate titanate (PZT) fibers have many advantages over the traditional bulk PZT sensors for embedded sensor applications. PFCSs as embedded sensors will be an ideal choice to continuously monitor the stress/strain levels and health conditions of composite structures. PFCSs are highly flexible, easily embeddable, have high compatibility with composite structures, and also provides manufacturing flexibility. This research is focused on examining the effects of embedding PFCS sensors (macro-fiber composite (MFC) and piezoelectric fiber composite (PFC)) on the structural integrity of glass-fiber–epoxy composite laminates. The strengths of composite materials with embedded PFCSs and conventional PZT sensors were compared, and the advantages of PFCS sensors over PZTs were demonstrated. Initially a numerical simulation study is performed to understand the local stress/strain field near the embedded sensor region inside a composite specimen. High stress concentration regions were observed near the embedded sensor corner edge. Using PFCS leads to a reduction of 56% in longitudinal stress concentration and 38% in transverse stress concentration, when compared to using the conventional PZTs as embedded sensors. In-plane tensile, in-plane tension–tension fatigue, and short beam strength tests are performed to evaluate the strengths/behavior of the composite specimens containing embedded PFCS. From the tensile test it is observed that embedding PFCS and PZT sensors in the composite structures leads to a reduction in ultimate strength by 3 and 6% respectively. From the fatigue test results it is concluded that both embedded PFCS and PZT sensors do not have a significant effect on the fatigue behavior of the composite specimens. From the short beam strength test it is found that embedding PFCS and PZT sensors leads to a reduction in shear strength by 7 and 15% respectively. Overall the pure PZT

The effects of embedded piezoelectric fiber composite sensors on the structural integrity of glass-fiber-epoxy composite laminate

Science.gov (United States)

Konka, Hari P.; Wahab, M. A.; Lian, K.

2012-01-01

Piezoelectric fiber composite sensors (PFCSs) made from micro-sized lead zirconate titanate (PZT) fibers have many advantages over the traditional bulk PZT sensors for embedded sensor applications. PFCSs as embedded sensors will be an ideal choice to continuously monitor the stress/strain levels and health conditions of composite structures. PFCSs are highly flexible, easily embeddable, have high compatibility with composite structures, and also provides manufacturing flexibility. This research is focused on examining the effects of embedding PFCS sensors (macro-fiber composite (MFC) and piezoelectric fiber composite (PFC)) on the structural integrity of glass-fiber-epoxy composite laminates. The strengths of composite materials with embedded PFCSs and conventional PZT sensors were compared, and the advantages of PFCS sensors over PZTs were demonstrated. Initially a numerical simulation study is performed to understand the local stress/strain field near the embedded sensor region inside a composite specimen. High stress concentration regions were observed near the embedded sensor corner edge. Using PFCS leads to a reduction of 56% in longitudinal stress concentration and 38% in transverse stress concentration, when compared to using the conventional PZTs as embedded sensors. In-plane tensile, in-plane tension-tension fatigue, and short beam strength tests are performed to evaluate the strengths/behavior of the composite specimens containing embedded PFCS. From the tensile test it is observed that embedding PFCS and PZT sensors in the composite structures leads to a reduction in ultimate strength by 3 and 6% respectively. From the fatigue test results it is concluded that both embedded PFCS and PZT sensors do not have a significant effect on the fatigue behavior of the composite specimens. From the short beam strength test it is found that embedding PFCS and PZT sensors leads to a reduction in shear strength by 7 and 15% respectively. Overall the pure PZT sensors

An Optimal Image-Based Method for Identification of Acoustic Emission (AE) Sources in Plate-Like Structures Using a Lead Zirconium Titanate (PZT) Sensor Array

Science.gov (United States)

Zhou, Li

2018-01-01

This paper proposes an innovative method for identifying the locations of multiple simultaneous acoustic emission (AE) events in plate-like structures from the view of image processing. By using a linear lead zirconium titanate (PZT) sensor array to record the AE wave signals, a reverse-time frequency-wavenumber (f-k) migration is employed to produce images displaying the locations of AE sources by back-propagating the AE waves. Lamb wave theory is included in the f-k migration to consider the dispersive property of the AE waves. Since the exact occurrence time of the AE events is usually unknown when recording the AE wave signals, a heuristic artificial bee colony (ABC) algorithm combined with an optimal criterion using minimum Shannon entropy is used to find the image with the identified AE source locations and occurrence time that mostly approximate the actual ones. Experimental studies on an aluminum plate with AE events simulated by PZT actuators are performed to validate the applicability and effectiveness of the proposed optimal image-based AE source identification method. PMID:29466310

An Optimal Image-Based Method for Identification of Acoustic Emission (AE) Sources in Plate-Like Structures Using a Lead Zirconium Titanate (PZT) Sensor Array.

Science.gov (United States)

Yan, Gang; Zhou, Li

2018-02-21

This paper proposes an innovative method for identifying the locations of multiple simultaneous acoustic emission (AE) events in plate-like structures from the view of image processing. By using a linear lead zirconium titanate (PZT) sensor array to record the AE wave signals, a reverse-time frequency-wavenumber (f-k) migration is employed to produce images displaying the locations of AE sources by back-propagating the AE waves. Lamb wave theory is included in the f-k migration to consider the dispersive property of the AE waves. Since the exact occurrence time of the AE events is usually unknown when recording the AE wave signals, a heuristic artificial bee colony (ABC) algorithm combined with an optimal criterion using minimum Shannon entropy is used to find the image with the identified AE source locations and occurrence time that mostly approximate the actual ones. Experimental studies on an aluminum plate with AE events simulated by PZT actuators are performed to validate the applicability and effectiveness of the proposed optimal image-based AE source identification method.

Magnetic-Field-Orientation Dependent Magnetoelectric Effect in FeBSiC/PZT/FeBSiC Composites

Directory of Open Access Journals (Sweden)

Jun-Xian Ye

2014-01-01

Full Text Available We investigate the magnetic-field-orientation dependent magnetoelectric (ME effect in the FeBSiC/Pb(Zr,TiO3(PZT/FeBSiC laminates. It is shown that, by only using the bias-magnetic-field dependent ME response measured with the magnetic-field parallel to the surface plane of PZT slab, the magnetic-field-orientation dependent ME coefficient upon magnetic-fields of various amplitudes can be obtained via computer simulations. The simulation results match well the experimental measurements, demonstrating the applicability of the ME laminates-based sensors in detecting magnetic-fields with uncertain amplitudes and/or orientations in environment.

PZT-5A4/PA and PZT-5A4/PDMS piezoelectric composite bimorphs

NARCIS (Netherlands)

Babu, I.; Hendrix, M.M.R.M.; With, de G.

2014-01-01

Disc type reinforced piezoelectric composite bimorphs with series connection were designed and the performance was investigated. The composite bimorphs (PZT/PA and PZT/PDMS (40/60 vol%)) were successfully fabricated by a compression molding and solution casting technique. The charge developed at an

Screen printed PZT/PZT thick film bimorph MEMS cantilever device for vibration energy harvesting

DEFF Research Database (Denmark)

Xu, R.; Lei, A.; Christiansen, T. L.

2011-01-01

We present a MEMS-based PZT/PZT thick film bimorph vibration energy harvester with an integrated silicon proof mass. The most common piezoelectric energy harvesting devices utilize a cantilever beam of a non piezoelectric material as support beneath or in-between the piezoelectric material...

Flexoelectricity in PZT Nanoribbons and Biomembranes

Science.gov (United States)

2015-01-09

Flexoelectricity in PZT Nanoribbons and Biomembranes The objective of this grant was to study flexoelectric phenomena in solids and in biomembranes...Flexoelectricity in PZT Nanoribbons and Biomembranes Report Title The objective of this grant was to study flexoelectric phenomena in solids and...producing PZT nanoribbons for energy harvesters. (a) Papers published in peer-reviewed journals (N/A for none) Enter List of papers submitted or

Adjustability of resonance frequency by external magnetic field and bias electric field of sandwich magnetoelectric PZT/NFO/PZT composites

Energy Technology Data Exchange (ETDEWEB)

Xu, Ling-Fang; Feng, Xing; Sun, Kang; Liang, Ze-Yu; Xu, Qian; Liang, Jia-Yu; Yang, Chang-Ping [Hubei University, Hubei Key Laboratory of Ferro and Piezoelectric Materials and Devices, Faculty of Physics and Electronic Science, Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Wuhan (China)

2017-07-15

Sandwich magnetoelectric composites of PZT/NFO/PZT (PNP) have been prepared by laminating PZT5, NiFe{sub 2}O{sub 4}, and PZT5 ceramics in turn with polyvinyl alcohol (PVA) paste. A systematic study of structural, magnetic and ferroelectric properties is undertaken. Structural studies carried out by X-ray diffraction indicate formation of cubic perovskite phase of PZT5 ceramic and cubic spinel phase of NiFe{sub 2}O{sub 4} ceramic. As increasing the content of PZT5 phase, ferroelectric loops and magnetic loops of PNP composites showed increasing remnant electric polarizations and decreasing remnant magnetic moments separately. Both external magnetic fields and bias voltages could regulate the basal radial resonance frequency of the composites, which should be originated with the transformation and coupling of the stress between the piezoelectric phase and magnetostrictive phase. Such magnetoelectric composite provides great opportunities for electrostatically tunable devices. (orig.)

DEVELOPMENT OF SIGNAL PROCESSING TOOLS AND HARDWARE FOR PIEZOELECTRIC SENSOR DIAGNOSTIC PROCESSES

Energy Technology Data Exchange (ETDEWEB)

OVERLY, TIMOTHY G. [Los Alamos National Laboratory; PARK, GYUHAE [Los Alamos National Laboratory; FARRAR, CHARLES R. [Los Alamos National Laboratory

2007-02-09

This paper presents a piezoelectric sensor diagnostic and validation procedure that performs in -situ monitoring of the operational status of piezoelectric (PZT) sensor/actuator arrays used in structural health monitoring (SHM) applications. The validation of the proper function of a sensor/actuator array during operation, is a critical component to a complete and robust SHM system, especially with the large number of active sensors typically involved. The method of this technique used to obtain the health of the PZT transducers is to track their capacitive value, this value manifests in the imaginary part of measured electrical admittance. Degradation of the mechanical/electric properties of a PZT sensor/actuator as well as bonding defects between a PZT patch and a host structure can be identified with the proposed procedure. However, it was found that temperature variations and changes in sensor boundary conditions manifest themselves in similar ways in the measured electrical admittances. Therefore, they examined the effects of temperature variation and sensor boundary conditions on the sensor diagnostic process. The objective of this study is to quantify and classify several key characteristics of temperature change and to develop efficient signal processing techniques to account for those variations in the sensor diagnostis process. In addition, they developed hardware capable of making the necessary measurements to perform the sensor diagnostics and to make impedance-based SHM measurements. The paper concludes with experimental results to demonstrate the effectiveness of the proposed technique.

Influence of processing parameters on PZT thick films

International Nuclear Information System (INIS)

Huang, Oliver; Bandyopadhyay, Amit; Bose, Susmita

2005-01-01

We have studied influence of processing parameters on the microstructure and ferroelectric properties of lead zirconate titanate (PZT)-based thick films in the range of 5-25 μm. PZT and 2% La-doped PZT thick films were processed using a modified sol-gel process. In this process, PZT- and La-doped PZT powders were first prepared via sol-gel. These powders were calcined and then used with respective sols to form a slurry. Slurry composition was optimized to spin-coat thick films on platinized Si substrate (Si/SiO 2 /Ti/Pt). Spinning rate, acceleration and slurry deposition techniques were optimized to form thick films with uniform thickness and without any cracking. Increasing solids loading was found to enhance the surface smoothness of the film and decrease porosity. Films were tested for their electrical properties and ferroelectric fatigue response. The maximum polarization obtained was 40 μC/cm 2 at 250 kV/cm for PZT thick film and 30 μC/cm 2 at 450 kV/cm for La-doped PZT thick film. After 10 9 cycles of fatiguing at 35 kHz, La-doped PZT showed better resistance for ferroelectric fatigue compared with un-doped PZT films

Very high frequency (beyond 100 MHz) PZT kerfless linear arrays.

Science.gov (United States)

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

2009-10-01

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-microm PZT thick film fabricated from PZT-5H powder/solution composite and a piece of 15-microm 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).

Sputtered highly oriented PZT thin films for MEMS applications

Science.gov (United States)

Kalpat, Sriram S.

Recently there has been an explosion of interest in the field of micro-electro-mechanical systems (MEMS). MEMS device technology has become critical in the growth of various fields like medical, automotive, chemical, and space technology. Among the many applications of ferroelectric thin films in MEMS devices, microfluidics is a field that has drawn considerable amount of research from bio-technology industries as well as chemical and semiconductor manufacturing industries. PZT thin films have been identified as best suited materials for micro-actuators and micro-sensors used in MEMS devices. A promising application for piezoelectric thin film based MEMS devices is disposable drug delivery systems that are capable of sensing biological parameters, mixing and delivering minute and precise amounts of drugs using micro-pumps or micro mixers. These devices call for low driving voltages, so that they can be battery operated. Improving the performance of the actuator material is critical in achieving battery operated disposal drug delivery systems. The device geometry and power consumption in MEMS devices largely depends upon the piezoelectric constant of the films, since they are most commonly used to convert electrical energy into a mechanical response of a membrane or cantilever and vice versa. Phenomenological calculation on the crystal orientation dependence of piezoelectric coefficients for PZT single crystal have reported a significant enhancement of the piezoelectric d33 constant by more than 3 times along [001] in the rhombohedral phase as compared to the conventionally used orientation PZT(111) since [111] is the along the spontaneous polarization direction. This could mean considerable improvement in the MEMS device performance and help drive the operating voltages lower. The motivation of this study is to investigate the crystal orientation dependence of both dielectric and piezoelectric coefficients of PZT thin films in order to select the appropriate

Development of a stress sensor based on the piezoelectric lead zirconate titanate for impact stress measurement

Science.gov (United States)

Liu, Yiming; Xu, Bin; Li, Lifei; Li, Bing

2012-04-01

The measurement of stress of concrete structures under impact loading and other strong dynamic loadings is crucial for the monitoring of health and damage detection. Due to its main advantages including availability, extremely high rigidity, high natural frequency, wide measuring range, high stability, high reproducibility, high linearity and wide operating temperature range, piezoelectric (Lead Zirconate Titanate, PZT) ceramic materials has been a widely used smart material for both sensing and actuation for monitoring and control in engineering structures. In this paper, a kind of stress sensor based on piezoelectric ceramics for impact stress measuring of concrete structures is developed. Because the PZT is fragile, in order to employ it for the health monitoring of concrete structures, special handling and treatment should be taken to protect the PZT and to make it survive and work properly in concrete. The commercially available PZT patch with lead wires is first applied with an insulation coating to prevent water and moisture damage, and then is packaged by jacketing it by two small precasted cylinder concrete blocks with enough strength to form a smart aggregate (SA). The employed PZT patch has a dimension of 10mm x 10mm x 0.3mm. In order to calibrate the PZT based stress sensor for impact stress measuring, a dropping hammer was designed and calibration test on the sensitivity of the proposed transducer was carried out with an industry charge amplifier. The voltage output of the stress sensor and the impact force under different free falling heights and impact mass were recorded with a high sampling rate data acquisition system. Based on the test measurements, the sensibility of the PZT based stress sensor was determined. Results show that the output of the PZT based stress sensor is proportional to the stress level and the repeatability of the measurement is very good. The self-made piezoelectric stress sensor can be easily embedded in concrete and provide

Embedded 3D electromechanical impedance model for strength monitoring of concrete using a PZT transducer

International Nuclear Information System (INIS)

Wang, Dansheng; Song, Hongyuan; Zhu, Hongping

2014-01-01

The electromechanical (EM) impedance approach in which piezoelectric ceramics (PZT) simultaneously act as both a sensor and an actuator due to their direct and inverse piezoelectric effects has emerged as a powerful tool for structural health monitoring in recent years. This paper formulates a new 3D electromechanical impedance model that characterizes the interaction between an embedded square PZT transducer and the host structure based on the effective impedance. The proposed formulations can be conveniently used to extract the mechanical impedance of the host structure from the electromechanical admittance measurements of an embedded PZT patch. The proposed model is verified by experimental and numerical results from a smart concrete cube in which a square PZT transducer is embedded. Subsequently, this paper also presents a new methodology to monitor the compressive strength of concrete based on the effective mechanical impedance. By extracting the effective mechanical impedances from the electromechanical admittance signatures, measuring the compressive strength of the concrete cubes at different ages and combining these measurements with the index of the correlation coefficient (CC), a linear correlation between the concrete strength gain and the CC of the real mechanical admittances was found. The proposed approach is found to be feasible to monitor the compressive strength of concrete by age. (paper)

Piezo-sensor self-diagnostics using electrical impedance measurements.

Energy Technology Data Exchange (ETDEWEB)

Park, G. H. (Gyu Hae); Farrar, C. R. (Charles R.); Rutherford, A. C. (Amanda C.); Robertson, A. N. (Amy N.)

2004-01-01

This paper present the piezoelectric sensor self-diagnostic procedure that performs in-situ monitoring of the operational status of piezoelectric materials (PZT) used for sensors and actuators in structural health monitoring (SHM) applications. The use of active-sensing piezoelectric materials has received considerable attention in the SHM community. A critical aspect of the piezoelectric active-sensing technologies is that usually large numbers of distributed sensors and actuators are needed to perform the required monitoring process. The sensor/actuator self-diagnostic procedure, where the sensors/actuators are confirmed to be functioning properly during operation, is therefore a critical component to successfully complete the SHM process and to minimize the false indication regarding the structural health. The basis of this procedure is to track the changes in the capacitive value of piezoelectric materials resulting from the sensor failure, which is manifested in the imaginary part of the measured electrical admittances. Furthermore, through the analytical and experimental investigation, it is confirmed that the bonding layer between the PZT and a host structure significantly contributes to the measured capacitive values. Therefore, by monitoring the imaginary part of the admittances, one can quantitatively assess the degradation of the mechanical/electrical properties of the PZT and its attachment to a host structure. This paper concludes with an experimental example to demonstrate the feasibility of the proposed sensor-diagnostic procedure.

Piezoelectric power generation for sensor applications: design of a battery-less wireless tire pressure sensor

Science.gov (United States)

Makki, Noaman; Pop-Iliev, Remon

2011-06-01

An in-wheel wireless and battery-less piezo-powered tire pressure sensor is developed. Where conventional battery powered Tire Pressure Monitoring Systems (TPMS) are marred by the limited battery life, TPMS based on power harvesting modules provide virtually unlimited sensor life. Furthermore, the elimination of a permanent energy reservoir simplifies the overall sensor design through the exclusion of extra circuitry required to sense vehicle motion and conserve precious battery capacity during vehicle idling periods. In this paper, two design solutions are presented, 1) with very low cost highly flexible piezoceramic (PZT) bender elements bonded directly to the tire to generate power required to run the sensor and, 2) a novel rim mounted PZT harvesting unit that can be used to power pressure sensors incorporated into the valve stem requiring minimal change to the presently used sensors. While both the designs eliminate the use of environmentally unfriendly battery from the TPMS design, they offer advantages of being very low cost, service free and easily replaceable during tire repair and replacement.

Carbon Nanotube Composite SHM Sensor using Additive Manufacturing

Data.gov (United States)

National Aeronautics and Space Administration — We propose to develop a piezoelectric sensors made of carbon nanotube and lead zirconium titanate (PZT) nanopower dispersed in a polymer matrix. These sensors will...

Comparison of PZN-PT, PMN-PT single crystals and PZT ceramic for vibration energy harvesting

International Nuclear Information System (INIS)

Yang, Zhengbao; Zu, Jean

2016-01-01

Highlights: • Systematic analysis of PMN-PT and PZN-PT single crystals for energy harvesters. • Performance analysis and comparison under various conditions. • Discussion of the effect of the SSHI technique on single crystal energy harvesters. • Efficiency analysis in both on-resonance and off-resonance conditions. - Abstract: Vibration energy harvesting has a great potential to achieve self-powered operations for wireless sensors, wearable devices and medical electronics, and thus has attracted much attention in academia and industry. The majority of research into this subject has focused on the piezoelectric effect of synthetic materials, especially the perovskite PZT ceramics. Recently the new-generation piezoelectric materials PMN-PT and PZN-PT single crystals have gained significant interest because of their outstanding piezoelectric properties. They can be used to replace the widely-adopted PZT ceramics for improving energy harvesters’ performance substantially. However, there is little research on comparing PMN-PT and PZN-PT energy harvesters against PZT harvesters. In this paper, we present a systematic comparison between vibration energy harvesters using the PMN-PT, PZN-PT single crystals and those using the PZT ceramics. Key properties of the three materials are summarized and compared. The performance of the PMN-PT and PZN-PT energy harvesters is characterized under different conditions (beam length, resistance, frequency, excitation strength, and backward coupling effect), and is quantitatively compared with the PZT counterpart. Furthermore, the effect of the synchronized switch harvesting on inductor (SSHI) circuit on the three harvesters is discussed. The experimental results indicate that energy harvesters using the PMN-PT and PZN-PT single crystals can significantly outperform those using the PZT ceramics. This study provides a strong base for future research on high-performance energy harvesters using the new PMN-PT and PZN-PT single

Influence of binding material of PZT coating on microresonator's electrical and mechanical properties

Science.gov (United States)

Janusas, Giedrius; Guobiene, Asta; Palevicius, Arvydas; Brunius, Alfredas; Cekas, Elingas; Baltrusaitis, Valentinas; Sakalys, Rokas

2017-06-01

Microresonators are fundamental components integrated in hosts of MEMS applications: covering the automotive sector, the telecommunication industry, electronic equipment for surface/material characterization and motion sensing, and etc. The aim of this paper is to investigate the mechanical and electrical properties of PZT film fabricated with three binding materials: polyvinyl butyral (PVB), polymethyl methacrylate (PMMA) and polystyrene (PS) and to evaluate applicability in control of microresonators Q factor. Micro particles of PZT powder were mixed with 20% solution of PVB, PMMA and PS in benzyl alcohol. For investigation of mechanical and electrical properties multilayer cantilevers were made. Obtained PZT and polymer paste was screen printed on copper (thickness 40 μm) using polyester monofilament screen meshes (layer thickness 50 μm) and dried for 30 min at 100°C. Electric dipoles of the PZT particles in composite material were aligned using high voltage generator (5 kV) and a custom-made holder. Electric field was held for 30 min. Surfaces of the applied films were investigated by Atomic Force Microscope NanoWizard(R)3 NanoScience. Dynamic and electrical characteristics of the multilayer were investigated using laser triangular displacement sensor LK-G3000. The measured vibration amplitude and generated electrical potential was collected with USB oscilloscope PicoScope 3424. As the results showed, these cantilevers were able to transform mechanical strain energy into electric potential and, v.v. However, roughness of PZT coatings with PMMA and PS were higher, what could be the reason of the worse quality of the top electrode. However, the main advantage of the created composite piezoelectric material is the possibility to apply it on any uniform or non-uniform vibrating surface and to transform low frequency vibrations into electricity.

Acoustic Emission Detection of Macro-Cracks on Engraving Tool Steel Inserts during the Injection Molding Cycle Using PZT Sensors

Directory of Open Access Journals (Sweden)

Aleš Hančič

2013-05-01

Full Text Available This paper presents an improved monitoring system for the failure detection of engraving tool steel inserts during the injection molding cycle. This system uses acoustic emission PZT sensors mounted through acoustic waveguides on the engraving insert. We were thus able to clearly distinguish the defect through measured AE signals. Two engraving tool steel inserts were tested during the production of standard test specimens, each under the same processing conditions. By closely comparing the captured AE signals on both engraving inserts during the filling and packing stages, we were able to detect the presence of macro-cracks on one engraving insert. Gabor wavelet analysis was used for closer examination of the captured AE signals’ peak amplitudes during the filling and packing stages. The obtained results revealed that such a system could be used successfully as an improved tool for monitoring the integrity of an injection molding process.

Lattice strain induced multiferroicity in PZT-CFO particulate composite

Science.gov (United States)

Pradhan, Lagen Kumar; Pandey, Rabichandra; Kumar, Rajnish; Kar, Manoranjan

2018-02-01

Lead Zirconate Titanate [Pb(Zr0.52Ti0.48)O3/PZT] and Cobalt Ferrite [CoFe2O4/CFO] based multiferroic composites [(1-x)PZT-(x)CFO] with (x = 0.10-0.40) have been prepared to study its magnetoelectric (ME) and multiferroic properties. X-ray diffraction method along with the Rietveld refinement technique reveals that the crystal symmetries corresponding to PZT and CFO exist independently in the composites. The effect of interfacial strain on lattice distortion in PZT has been observed. It is well correlated with the magnetoelectric coupling of the composites. Dispersion behavior of dielectric constant with frequency can be explained by the modified Debye model. Different relaxation phenomena have been observed in PZT-CFO particulate composites. The ferroelectric properties of composites decrease with the increase in percentage of CFO in the composite. Both saturation (Ms) and remanent (Mr) magnetization increase with the increase in CFO content in the composite. The maximum ME coupling was found to be 1.339 pC/cm2 Oe for the composition (0.80) PZT-(0.20) CFO at the application of maximum magnetic field of 50 Oe. The multiferroic properties in CFO-PZT can be explained by the lattice strain at the CFO-PZT interfaces.

Fluid Vessel Quantity using Non-Invasive PZT Technology Flight Volume Measurements Under Zero G Analysis

Science.gov (United States)

Garofalo, Anthony A.

2013-01-01

The purpose of the project is to perform analysis of data using the Systems Engineering Educational Discovery (SEED) program data from 2011 and 2012 Fluid Vessel Quantity using Non-Invasive PZT Technology flight volume measurements under Zero G conditions (parabolic Plane flight data). Also experimental planning and lab work for future sub-orbital experiments to use the NASA PZT technology for fluid volume measurement. Along with conducting data analysis of flight data, I also did a variety of other tasks. I provided the lab with detailed technical drawings, experimented with 3d printers, made changes to the liquid nitrogen skid schematics, and learned how to weld. I also programmed microcontrollers to interact with various sensors and helped with other things going on around the lab.

A concept of wireless and passive very-high temperature sensor

Science.gov (United States)

Nicolay, P.; Matloub, R.; Bardong, J.; Mazzalai, A.; Muralt, P.

2017-05-01

There is a need for sensors capable operating at temperatures above 1000 °C. We describe an innovative sensor that might achieve this goal. The sensor comprises two main elements: a thermocouple and a surface acoustic wave (SAW) strain sensor. The cold junction of the thermocouple is electrically connected to a highly piezoelectric thin layer, deposited on top of a SAW substrate. In operation, the voltage generated by the temperature gradient between the hot (>1000 °C) and cold junction (PZT), which could increase the sensitivity by factors of 3 and 20, as estimated from their transverse piezoelectric coefficients. As a first step in this direction, thin PZT layers have been deposited on Y-Z LN.

Ferroelectric devices using lead zirconate titanate (PZT) nanoparticles.

Science.gov (United States)

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 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.

Strain sensors for high field pulse magnets

Energy Technology Data Exchange (ETDEWEB)

Martinez, Christian [Los Alamos National Laboratory; Zheng, Yan [Los Alamos National Laboratory; Easton, Daniel [Los Alamos National Laboratory; Farinholt, Kevin M [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory

2009-01-01

In this paper we present an investigation into several strain sensing technologies that are being considered to monitor mechanical deformation within the steel reinforcement shells used in high field pulsed magnets. Such systems generally operate at cryogenic temperatures to mitigate heating issues that are inherent in the coils of nondestructive, high field pulsed magnets. The objective of this preliminary study is to characterize the performance of various strain sensing technologies at liquid nitrogen temperatures (-196 C). Four sensor types are considered in this investigation: fiber Bragg gratings (FBG), resistive foil strain gauges (RFSG), piezoelectric polymers (PVDF), and piezoceramics (PZT). Three operational conditions are considered for each sensor: bond integrity, sensitivity as a function of temperature, and thermal cycling effects. Several experiments were conducted as part of this study, investigating adhesion with various substrate materials (stainless steel, aluminum, and carbon fiber), sensitivity to static (FBG and RFSG) and dynamic (RFSG, PVDF and PZT) load conditions, and sensor diagnostics using PZT sensors. This work has been conducted in collaboration with the National High Magnetic Field Laboratory (NHMFL), and the results of this study will be used to identify the set of sensing technologies that would be best suited for integration within high field pulsed magnets at the NHMFL facility.

Experimental characterization of PZT fibers using IDE electrodes

Science.gov (United States)

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.

Hyperfine interaction measurements on ceramics: PZT revisited

International Nuclear Information System (INIS)

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

2007-01-01

The solid solution of PbZr 1- x Ti x O 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

Flexible graphene–PZT ferroelectric nonvolatile memory

International Nuclear Information System (INIS)

Lee, Wonho; Ahn, Jong-Hyun; Kahya, Orhan; Toh, Chee Tat; Özyilmaz, Barbaros

2013-01-01

We report the fabrication of a flexible graphene-based nonvolatile memory device using Pb(Zr 0.35 ,Ti 0.65 )O 3 (PZT) as the ferroelectric material. The graphene and PZT ferroelectric layers were deposited using chemical vapor deposition and sol–gel methods, respectively. Such PZT films show a high remnant polarization (P r ) of 30 μC cm −2 and a coercive voltage (V c ) of 3.5 V under a voltage loop over ±11 V. The graphene–PZT ferroelectric nonvolatile memory on a plastic substrate displayed an on/off current ratio of 6.7, a memory window of 6 V and reliable operation. In addition, the device showed one order of magnitude lower operation voltage range than organic-based ferroelectric nonvolatile memory after removing the anti-ferroelectric behavior incorporating an electrolyte solution. The devices showed robust operation in bent states of bending radii up to 9 mm and in cycling tests of 200 times. The devices exhibited remarkable mechanical properties and were readily integrated with plastic substrates for the production of flexible circuits. (paper)

Flexible graphene-PZT ferroelectric nonvolatile memory.

Science.gov (United States)

Lee, Wonho; Kahya, Orhan; Toh, Chee Tat; Ozyilmaz, Barbaros; Ahn, Jong-Hyun

2013-11-29

We report the fabrication of a flexible graphene-based nonvolatile memory device using Pb(Zr0.35,Ti0.65)O3 (PZT) as the ferroelectric material. The graphene and PZT ferroelectric layers were deposited using chemical vapor deposition and sol–gel methods, respectively. Such PZT films show a high remnant polarization (Pr) of 30 μC cm−2 and a coercive voltage (Vc) of 3.5 V under a voltage loop over ±11 V. The graphene–PZT ferroelectric nonvolatile memory on a plastic substrate displayed an on/off current ratio of 6.7, a memory window of 6 V and reliable operation. In addition, the device showed one order of magnitude lower operation voltage range than organic-based ferroelectric nonvolatile memory after removing the anti-ferroelectric behavior incorporating an electrolyte solution. The devices showed robust operation in bent states of bending radii up to 9 mm and in cycling tests of 200 times. The devices exhibited remarkable mechanical properties and were readily integrated with plastic substrates for the production of flexible circuits.

Fabrication and comparison of PMN-PT single crystal, PZT and PZT-based 1-3 composite ultrasonic transducers for NDE applications.

Science.gov (United States)

Kim, Ki-Bok; Hsu, David K; Ahn, Bongyoung; Kim, Young-Gil; Barnard, Daniel J

2010-08-01

This paper describes fabrication and comparison of PMN-PT single crystal, PZT, and PZT-based 1-3 composite ultrasonic transducers for NDE applications. As a front matching layer between test material (Austenite stainless steel, SUS316) and piezoelectric materials, alumina ceramics was selected. The appropriate acoustic impedance of the backing materials for each transducer was determined based on the results of KLM model simulation. Prototype ultrasonic transducers with the center frequencies of approximately 2.25 and 5MHz for contact measurement were fabricated and compared to each other. The PMN-PT single crystal ultrasonic transducer shows considerably improved performance in sensitivity over the PZT and PZT-based 1-3 composite ultrasonic transducers. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Characterization of cement-based materials using a reusable piezoelectric impedance-based sensor

Science.gov (United States)

Tawie, R.; Lee, H. K.

2011-08-01

This paper proposes a reusable sensor, which employs a piezoceramic (PZT) plate as an active sensing transducer, for non-destructive monitoring of cement-based materials based on the electromechanical impedance (EMI) sensing technique. The advantage of the sensor design is that the PZT can be easily removed from the set-up and re-used for repetitive tests. The applicability of the sensor was demonstrated for monitoring of the setting of cement mortar. EMI measurements were performed using an impedance analyzer and the transformation of the specimen from the plastic to solid state was monitored by automatically measuring the changes in the PZT conductance spectra with respect to curing time using the root mean square deviation (RMSD) algorithm. In another experiment, drying-induced moisture loss of a hardened mortar specimen at saturated surface dry (SSD) condition was measured, and monitored using the reusable sensor to establish a correlation between the RMSD values and moisture loss rate. The reusable sensor was also demonstrated for detecting progressive damages imparted on a mortar specimen attached with the sensor under several loading levels before allowing it to load to failure. Overall, the reusable sensor is an effective and efficient monitoring device that could possibly be used for field application in characterization of cement-based materials.

Characterization of cement-based materials using a reusable piezoelectric impedance-based sensor

International Nuclear Information System (INIS)

Tawie, R; Lee, H K

2011-01-01

This paper proposes a reusable sensor, which employs a piezoceramic (PZT) plate as an active sensing transducer, for non-destructive monitoring of cement-based materials based on the electromechanical impedance (EMI) sensing technique. The advantage of the sensor design is that the PZT can be easily removed from the set-up and re-used for repetitive tests. The applicability of the sensor was demonstrated for monitoring of the setting of cement mortar. EMI measurements were performed using an impedance analyzer and the transformation of the specimen from the plastic to solid state was monitored by automatically measuring the changes in the PZT conductance spectra with respect to curing time using the root mean square deviation (RMSD) algorithm. In another experiment, drying-induced moisture loss of a hardened mortar specimen at saturated surface dry (SSD) condition was measured, and monitored using the reusable sensor to establish a correlation between the RMSD values and moisture loss rate. The reusable sensor was also demonstrated for detecting progressive damages imparted on a mortar specimen attached with the sensor under several loading levels before allowing it to load to failure. Overall, the reusable sensor is an effective and efficient monitoring device that could possibly be used for field application in characterization of cement-based materials

Development of a PZT-based wireless digital monitor for composite impact monitoring

International Nuclear Information System (INIS)

Liu, Peipei; Yuan, Shenfang; Qiu, Lei

2012-01-01

One of the major concerns in the whole lifetime of composite materials in aircraft is their susceptibility to impact damage. And there has existed a need in recent years to develop an online structural health monitoring (SHM) system for impact monitoring. This paper proposes a new PZT-based wireless digital impact monitoring system development method aimed at giving a localized area for further inspection. Based on this method, a PZT-based wireless digital impact monitor (WDIM) with advantages of compactness, light weight, low power consumption and high efficiency is developed. Differently from conventional SHM systems, the complex analog circuits are removed and the whole process is achieved in a digital way by turning the output of the PZT sensor directly into a digital queue through a comparator. A simple but efficient sub-region location method is implemented in a field programmable gate array (FPGA) as the processing core of the WDIM to detect and record the impact events. In addition, wireless communication technology is used in the WDIM to transmit data and form a monitoring network. To illustrate the capability of the WDIM, a complete process dealing with an impact event is investigated and the stability of the WDIM is also evaluated in this paper. The WDIM shows its potential for real online applications in aircraft. (paper)

Standing wave brass-PZT square tubular ultrasonic motor.

Science.gov (United States)

Park, Soonho; He, Siyuan

2012-09-01

This paper reports a standing wave brass-PZT tubular ultrasonic motor. The motor is composed of a brass square tube with two teeth on each tube end. Four PZT plates are attached to the outside walls of the brass tube. The motor requires only one driving signal to excite vibration in a single bending mode to generate reciprocating diagonal trajectories of teeth on the brass tube ends, which drive the motor to rotate. Bi-directional rotation is achieved by exciting different pairs of PZT plates to switch the bending vibration direction. Through using the brass-PZT tube structure, the motor can take high magnitude vibration to achieve a high output power in comparison to PZT tube based ultrasonic motors. Prototypes are fabricated and tested. The dimension of the brass-PZT tube is 3.975mm×3.975mm×16mm. Measured performance is a no-load speed of >1000RPM, a stall torque of 370μNm and a maximum output power of 16 mW when a sinusoidal driving voltage of 50V is applied. The working frequencies of the motor are 46,050Hz (clockwise) and 46,200Hz (counter-clockwise). Copyright © 2012. Published by Elsevier B.V.

Using microwave for processing nanostructured PZT ceramics; Utilizacao de microondas no processamento de ceramicas nanoestruturadas de PZT

Energy Technology Data Exchange (ETDEWEB)

Lanza, A.C.; Berti, T.G.; Thomazini, D.; Gelfuso, M.V., E-mail: lanza.work@gmail.com [Universidade Federal de Itajuba (UNIFEI), MG (Brazil). Instituto de Engenharia Mecanica; Eiras, J.A. [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Dept. de Fisica

2012-07-01

The PZT ceramics have dielectric and piezoelectric properties of technological interest. The method of microwave assisted hydrothermal synthesis becomes interesting since it occurs in a closed environment, the low temperature and time, compared to conventional methods. In this work, PZT powders were dissolved in acid medium, and by adjusting the pH of the solutions obtained were precipitated, subjected to hydrothermal treatment at 120 °C for intervals of 15, 30 and 60 min. The powders were characterized by differential thermal and gravimetric analysis, X-ray diffraction and scanning electron microscopy. The results confirm the formation of PZT phase in one hour with particle size around 55 nm, showing the feasibility of the proposed method. (author)

Characterization of PZT thin films on metal substrates; Charakterisierung von PZT-Duennschichten auf Metallsubstraten

Energy Technology Data Exchange (ETDEWEB)

Dutschke, A.

2008-02-02

Lead zirconate titanate (PbZr{sub x}Ti{sub 1-x}O{sub 3},PZT) is one of the most applied ceramic materials because of its distinctive piezo- and ferroelectric properties. Prepared as thin films on flexible, metallic substrates it can be used for various applications as strain gauges, key switches, vibration dampers, microactuators and ultrasonic transducers. The aim of this work is to analyze the microstructure and the phase-content of PZT-thin films deposited on temperature- und acid-resistant hastelloy-sheets, to correlate the results with the ferroelectric and dielectric properties. It is demonstrated, that the specific variation of the microstructure can be achieved by different thermal treatments and the selective addition of Neodymium as dopant. Nd-doping leads to a shift of the maximum nucleation rate towards reduced temperatures and a decrease in the rate of growth compared to undoped films. The PZT-films are prepared by a sol-gel-process in fourfold multilayers with a composition near the morphotropic phase boundary, where the tetragonal und rhombohedral perovskite-phases coexist. The crystallisation in Nd-doped and undoped films takes place heterogeneously, preferentially at the interfaces and on the surface of the multilayered films as well as on the inner surface of pores within the films. For the first time, the Zr:Ti fluctuation phenomena emerging in sol-gel derived PZT films is related to the microstructure and the local phase content on a nanometer scale. In this connection it is proved, that long-distance Zr:Ti gradients arise preferentially before and during the crystallisation of the pyrochlore phase. During the following crystallisation of the perovskite phase, the crystallites grow across these gradients without modifying them. It is pointed out that the fluctuation in the Zr:Ti ratio has only minor influence on the amount of the tetragonal or rhombohedral distortion of the crystallites after the transition from the para- to the ferroelectric

Comparative face-shear piezoelectric properties of soft and hard PZT ceramics

Science.gov (United States)

Miao, Hongchen; Chen, Xi; Cai, Hairong; Li, Faxin

2015-12-01

The face-shear ( d 36 ) mode may be the most practical shear mode in piezoelectrics, while theoretically this mode cannot appear in piezoelectric ceramics because of its transversally isotropic symmetry. Recently, we realized piezoelectric coefficient d 36 up to 206pC/N in soft PbZr1-xTixO3 (PZT) ceramics via ferroelastic domain engineering [H. C. Miao and F. X. Li, Appl. Phys. Lett. 107, 122902 (2015)]. In this work, we further realized the face-shear mode in both hard and soft PZT ceramics including PZT-4 (hard), PZT-51(soft), and PZT-5H (soft) and investigated the electric properties systematically. The resonance methods are derived to measure the d 36 coefficients using both square patches and narrow bar samples, and the obtained values are consistent with that measured by a modified d 33 meter previously. For all samples, the pure d 36 mode can only appear near the resonance frequency, and the coupled d 36 - d 31 mode dominates off resonance. It is found that both the piezoelectric coefficient d 36 and the electromechanical coupling factor k 36 of soft PZT ceramics (PZT-5H and PZT-51) are considerably larger than those of the hard PZT ceramics (PZT-4). The obtained d 36 of 160-275pC/N, k 36 ˜ 0.24, and the mechanical quality factor Q 36 of 60-90 in soft PZT ceramics are comparable with the corresponding properties of the d 31 mode sample. Therefore, the d 36 mode in modified soft PZT ceramics is more promising for industrial applications such as face-shear resonators and shear horizontal wave generators.

Hyperfine interaction measurements on ceramics: PZT revisited

Energy Technology Data Exchange (ETDEWEB)

Guarany, Cristiano A. [Universidade Estadual Paulista (Unesp), Departmento de Fisica Quimica, Caixa Postal 31, 15.385-000 Ilha Solteira, SP (Brazil); Araujo, Eudes B. [Universidade Estadual Paulista (Unesp), Departmento de Fisica Quimica, Caixa Postal 31, 15.385-000 Ilha Solteira, SP (Brazil); Silva, Paulo R.J. [Centro Brasileiro de Pesquisas Fisicas-Rua Dr. Xavier Sigaud, 150, 22290-180 Rio de Janeiro, RJ (Brazil); Saitovitch, Henrique [Centro Brasileiro de Pesquisas Fisicas-Rua Dr. Xavier Sigaud, 150, 22290-180 Rio de Janeiro, RJ (Brazil)]. E-mail: henrique@cbpf.br

2007-02-01

The solid solution of PbZr{sub 1-} {sub x} Ti {sub x} O{sub 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.

Process induced poling and plasma induced damage of thin films PZT

NARCIS (Netherlands)

Wang, J.; Houwman, Evert Pieter; Salm, Cora; Nguyen, Duc Minh; Vergeer, Kurt; Schmitz, Jurriaan

2017-01-01

This paper treats processing sequence induced changes on PZT. Two kinds of metal-PZT-metal capacitors are compared. The top surface and sidewall of PZT in one kind of capacitor is directly bombarded by energetic particles during ion milling process, whereas PZT in the other kind of capacitor is not.

High sensitivity zero-biased magnetic field sensor based on multiphase laminate heterostructures with FeCuNbSiB nanocrystalline soft magnetic alloy

Science.gov (United States)

Qiu, Jing; Wen, Yumei; Li, Ping; Chen, Hengjia

2016-05-01

In this paper, a high sensitivity zero-biased magnetic field sensor based on multiphase laminate heterostructures consisting of FeCuNbSiB/Terfenol-D (Tb1-xDyxFe2)/PZT (Pb(Zr1-x,Tix)O3)/Terfenol-D/PZT/Ternol-D/FeCuNbSiB (FMPMPMF) is presented, whose ME coupling characteristics and sensing performances have been investigated. Compared to traditional Terfenol-D/PZT/Terfenol-D (MPM) and Terfenol-D/PZT/Terfenol-D/PZT/Terfenol-D (MPMPM) sensors, the zero-biased ME coupling characteristics of FMPMPMF sensor were significantly improved, owing to a build-in magnetic field in FeCuNbSiB/Terfenol-D layers. The optimum zero-biased resonant ME voltage coefficient of 3.02 V/Oe is achieved, which is 1.65 times as great as that of MPMPM and 2.51 times of MPM sensors. The mean value of low-frequency ME field coefficient of FMPMPMF reaches 122.53 mV/cm Oe, which is 2.39 times as great as that of MPMPM and 1.79 times of MPM sensors. Meanwhile, the induced zero-biased ME voltage of FMPMPMF sensor shows an excellent linear relationship to ac magnetic field both at the low frequency (1 kHz) and the resonant frequency (106.6 kHz). Remarkably, it indicates that the proposed zero-biased magnetic field sensor give the prospect of being able to applied to the field of highly sensitive ac magnetic field sensing.

Preparation and properties of porous PMN-PZT ceramics doped with strontium

International Nuclear Information System (INIS)

Zeng Tao; Dong Xianlin; Mao Chaoliang; Chen Shutao; Chen Heng

2006-01-01

The piezoelectric and dielectric properties of lead magnesium niobate-lead zirconate titanate (PMN-PZT) ceramics were investigated as a function of density for transducer applications. A decrease in density increased elastic compliance and improved acoustic impedance matching between PMN-PZT ceramics and ambient media. The reduced dielectric constant (ε 33 ) and enhanced hydrostatic figure of merit (d h g h ) of PMN-PZT were observed with decreased density. The results showed the d h g h of PMN-PZT ceramic with density of about 5.4 g/cm 3 reached 4000 x 10 -15 m 2 /N, and the ε 33 was very close to 2000, which demonstrates that porous PMN-PZT ceramic is a promising material for transducer applications. Moreover, the low density PMN-PZT ceramics exhibited lower dielectric loss than high density PMN-PZT ceramics during the temperature from 250 deg. C to 500 deg. C

PVDF-PZT nanocomposite film based self-charging power cell.

Science.gov (United States)

Zhang, Yan; Zhang, Yujing; Xue, Xinyu; Cui, Chunxiao; He, Bin; Nie, Yuxin; Deng, Ping; Lin Wang, Zhong

2014-03-14

A novel PVDF-PZT nanocomposite film has been proposed and used as a piezoseparator in self-charging power cells (SCPCs). The structure, composed of poly(vinylidene fluoride) (PVDF) and lead zirconate titanate (PZT), provides a high piezoelectric output, because PZT in this nanocomposite film can improve the piezopotential compared to the pure PVDF film. The SCPC based on this nanocomposite film can be efficiently charged up by the mechanical deformation in the absence of an external power source. The charge capacity of the PVDF-PZT nanocomposite film based SCPC in 240 s is ∼0.010 μA h, higher than that of a pure PVDF film based SCPC (∼0.004 μA h). This is the first demonstration of using PVDF-PZT nanocomposite film as a piezoseparator for SCPC, and is an important step for the practical applications of SCPC for harvesting and storing mechanical energy.

Optimization of sensing and feedback control for vibration/flutter of rotating disk by PZT actuators via air coupled pressure.

Science.gov (United States)

Yan, Tianhong; Xu, Xinsheng; Han, Jianqiang; Lin, Rongming; Ju, Bingfeng; Li, Qing

2011-01-01

In this paper, a feedback control mechanism and its optimization for rotating disk vibration/flutter via changes of air-coupled pressure generated using piezoelectric patch actuators are studied. A thin disk rotates in an enclosure, which is equipped with a feedback control loop consisting of a micro-sensor, a signal processor, a power amplifier, and several piezoelectric (PZT) actuator patches distributed on the cover of the enclosure. The actuator patches are mounted on the inner or the outer surfaces of the enclosure to produce necessary control force required through the airflow around the disk. The control mechanism for rotating disk flutter using enclosure surfaces bonded with sensors and piezoelectric actuators is thoroughly studied through analytical simulations. The sensor output is used to determine the amount of input to the actuator for controlling the response of the disk in a closed loop configuration. The dynamic stability of the disk-enclosure system, together with the feedback control loop, is analyzed as a complex eigenvalue problem, which is solved using Galerkin's discretization procedure. The results show that the disk flutter can be reduced effectively with proper configurations of the control gain and the phase shift through the actuations of PZT patches. The effectiveness of different feedback control methods in altering system characteristics and system response has been investigated. The control capability, in terms of control gain, phase shift, and especially the physical configuration of actuator patches, are also evaluated by calculating the complex eigenvalues and the maximum displacement produced by the actuators. To achieve a optimal control performance, sizes, positions and shapes of PZT patches used need to be optimized and such optimization has been achieved through numerical simulations.

PZT Thin-Film Micro Probe Device with Dual Top Electrodes

Science.gov (United States)

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

The effects of dimensional parameters on sensing and energy harvesting of an embedded PZT in a total knee replacement

Science.gov (United States)

Safaei, Mohsen; Anton, Steven R.

2016-04-01

Total Knee Replacement (TKR), one of the most common surgeries in the United States, is performed when the patient is experiencing significant amounts of pain or when knee functionality has become substantially degraded. Despite impressive recent developments, only about 85% of patients are satisfied with the pain reduction after one year. Therefore, structural health and performance monitoring are integral for intraoperative and postoperative feedback. In extension of the author's previous work, a new configuration for implementation of piezoelectric transducers in total knee replacement bearings is proposed and FEA modeling is performed to attain appropriate sensing and energy harvesting ability. The predicted force transmission ratio to the PZT (ratio of force applied to the bearing to force transferred to the embedded piezoelectric transducer) is about 6.2% compared to about 5% found for the previous encapsulated design. Dimensional parameters of the polyethylene bearing including the diameter and depth of the PZT pocket as well as the placement geometry of the PZT transducer within the bearing are hypothesized as the most influential parameters on the performance of the designed system. The results show a small change of 1% and 2.3% in the output of the system as a result of variation in the PZT location and pocket diameter, respectively. Whereas, the output of the system is significantly sensitive to the pocket depth; a pocket 0.01 mm deeper than the PZT transducer leads to no force transmission, and a pocket 0.15 mm shallower leads to full load transmission to the PZT. In order to develop a self-powered sensor, the amount of energy harvested from tibial forces for the proposed geometry is investigated.

Novel Damage Detection Techniques for Structural Health Monitoring Using a Hybrid Sensor

Directory of Open Access Journals (Sweden)

Dengjiang Wang

2016-01-01

Full Text Available This study presents a technique for detecting fatigue cracks based on a hybrid sensor monitoring system consisting of a combination of intelligent coating monitoring (ICM and piezoelectric transducer (PZT sensors. An experimental procedure using this hybrid sensor system was designed to monitor the cracks generated by fatigue testing in plate structures. A probability of detection (POD model that quantifies the reliability of damage detection for a specific sensor or the nondestructive testing (NDT method was used to evaluate the weight factor for the ICM and PZT sensors. To estimate the uncertainty of model parameters in this study, the Bayesian method was employed. Realistic data from fatigue testing was used to validate the overall method, and the results show that the novel damage detection technique using a hybrid sensor can quantify fatigue cracks more accurately than results obtained by conventional sensor methods.

PZT crack detection in suspension-based dual stage actuator [for HDDs

CERN Document Server

Yung Ping Yeh; Ku, C

2000-01-01

An impedance method is proposed to detect cracks of PZT bars in suspension based dual stage-actuators. The frequency response amplitude of impedance at the resonance of 1.95 MHz, the PZT bar width extension mode, was very sensitive to the cracks in PZT material. As cracks in the PZT bars propagated from invisible micro cracks to visible macro cracks, the impedance gain at 1.95 MHz dropped suddenly. (3 refs).

Performance of magnetoelectric PZT/Ni multiferroic system for energy harvesting application

Science.gov (United States)

Gupta, Reema; Tomar, Monika; Kumar, Ashok; Gupta, Vinay

2017-03-01

Magnetoelectric (ME) coefficient of Lead Zirconium Titanate (PZT) thin films has been probed for possible energy harvesting applications. Single phase PZT thin films have been deposited on nickel substrate (PZT/Ni) using pulsed laser deposition (PLD) technique. The effect of PLD process parameters on the ME coupling coefficient in the prepared systems has been investigated. The as grown PZT films on Ni substrate were found to be polycrystalline with improved ferroelectric and ferromagnetic properties. The electrical switching behavior of the PZT thin films were verified using capacitance voltage measurements, where well defined butterfly loops were obtained. The ME coupling coefficient was estimated to be in the range of 94.5 V cm-1 Oe-1-130.5 V cm-1 Oe-1 for PZT/Ni system, which is large enough for harnessing electromagnetic energy for subsequent applications.

Vibration based monitoring of stay cable force using wireless piezoelectric based strain sensor nodes

International Nuclear Information System (INIS)

Nguyen, Khac Duy; Kim, Jeong Tae

2012-01-01

This study presents a method to monitor cable force using wireless sensor nodes and piezoelectric sensors. The following approaches are carried out to achieve the objective. Firstly, the principle of piezoelectric materials (e.g., PZT) as strain sensors is reviewed. A cable force estimation method using dynamic features of cables measured by piezoelectric materials is presented. Secondly, the design of an automated cable force monitoring system using the data acquisition sensor node Imote2/SHM DAQ is described. The sensor node is originally developed by University of Illinois at Urbana champaign and is adopted in this study to monitor strain induced voltage from PZT sensors. The advantages of the system are cheap, and eligible for wireless communication and automated operation. Finally, the feasibility of the proposed monitoring system is evaluated on a lab scaled cable

Humidity and polarity influence on MIM PZT capacitor degradation and breakdown

NARCIS (Netherlands)

Wang, Jiahui; Salm, Cora; Houwman, Evert; Schmitz, Jurriaan; Nguyen, Minh

2016-01-01

This paper presents a reliability study on unpackaged metal-PZT-metal capacitors. Both ramped voltage stress (RVS) and time dependent dielectric breakdown (TDDB) measurements show that environmental humidity dramatically worsens the PZT reliability. Visible breakdown spots on the surface of PZT

Optimization of Sensing and Feedback Control for Vibration/Flutter of Rotating Disk by PZT Actuators via Air Coupled Pressure

Directory of Open Access Journals (Sweden)

Bingfeng Ju

2011-03-01

Full Text Available In this paper, a feedback control mechanism and its optimization for rotating disk vibration/flutter via changes of air-coupled pressure generated using piezoelectric patch actuators are studied. A thin disk rotates in an enclosure, which is equipped with a feedback control loop consisting of a micro-sensor, a signal processor, a power amplifier, and several piezoelectric (PZT actuator patches distributed on the cover of the enclosure. The actuator patches are mounted on the inner or the outer surfaces of the enclosure to produce necessary control force required through the airflow around the disk. The control mechanism for rotating disk flutter using enclosure surfaces bonded with sensors and piezoelectric actuators is thoroughly studied through analytical simulations. The sensor output is used to determine the amount of input to the actuator for controlling the response of the disk in a closed loop configuration. The dynamic stability of the disk-enclosure system, together with the feedback control loop, is analyzed as a complex eigenvalue problem, which is solved using Galerkin’s discretization procedure. The results show that the disk flutter can be reduced effectively with proper configurations of the control gain and the phase shift through the actuations of PZT patches. The effectiveness of different feedback control methods in altering system characteristics and system response has been investigated. The control capability, in terms of control gain, phase shift, and especially the physical configuration of actuator patches, are also evaluated by calculating the complex eigenvalues and the maximum displacement produced by the actuators. To achieve a optimal control performance, sizes, positions and shapes of PZT patches used need to be optimized and such optimization has been achieved through numerical simulations.

Synthesis and dielectric properties of ferroelectric-ferrimagnetic PZT-SFMO composites

Directory of Open Access Journals (Sweden)

Alexander V. Petrov

2017-03-01

Full Text Available Ferrimagnetic-ferroelectric composite materials on the base of Pb0.85Zr0.53Ti0.47O3– Sr2FeMoO6–δ (PZT-SFMO compounds have been prepared by a complex ceramic technology and a modified sol-gel synthesis. The dielectric properties of the PZT-SFMO composites with the PZT concentrations of 55 wt% and less, as well as of pure SFMO, are caused by the Maxwell-Wagner relaxation and a huge electrical conductivity. In contrast, in pure PZT the ferroelectric phase transition is clearly expressed in the static dielectric permittivity anomaly. Moreover, in all investigated composites, similarly to pure SFMO, the electrical conductivity anomaly is observed in the range from 560–540 K. This indicates that the composites with PZT concentrations of 55 wt% and higher are above the electrical and magnetic percolation threshold, in a good agreement with the excluded volume theory. In PZT-SFMO composites the DC electrical conductivity increases with SFMO concentration almost in a power law fashion, while the activation energy of the DC conductivity decreases under certain conditions.

Piezoelectric response of a PZT thin film to magnetic fields from permanent magnet and coil combination

Science.gov (United States)

Guiffard, B.; Seveno, R.

2015-01-01

In this study, we report the magnetically induced electric field E 3 in Pb(Zr0.57Ti0.43)O3 (PZT) thin films, when they are subjected to both dynamic magnetic induction (magnitude B ac at 45 kHz) and static magnetic induction ( B dc) generated by a coil and a single permanent magnet, respectively. It is found that highest sensitivity to B dc——is achieved for the thin film with largest effective electrode. This magnetoelectric (ME) effect is interpreted in terms of coupling between eddy current-induced Lorentz forces (stress) in the electrodes of PZT and piezoelectricity. Such coupling was evidenced by convenient modelling of experimental variations of electric field magnitude with both B ac and B dc induction magnitudes, providing imperfect open circuit condition was considered. Phase angle of E 3 versus B dc could also be modelled. At last, the results show that similar to multilayered piezoelectric-magnetostrictive composite film, a PZT thin film made with a simple manufacturing process can behave as a static or dynamic magnetic field sensor. In this latter case, a large ME voltage coefficient of under B dc = 0.3 T was found. All these results may provide promising low-cost magnetic energy harvesting applications with microsized systems.

Properties of RF-Sputtered PZT Thin Films with Ti/Pt Electrodes

Directory of Open Access Journals (Sweden)

Cui Yan

2014-01-01

Full Text Available Effect of annealing temperature and thin film thickness on properties of Pb(Zr0.53Ti0.47O3 (PZT thin film deposited via radiofrequency magnetron sputtering technique onto Pt/Ti/SiO2/Si substrate was investigated. Average grain sizes of the PZT thin film were measured by atomic force microscope; their preferred orientation was studied through X-ray diffraction analysis. Average residual stress in the thin film was estimated according to the optimized Stoney formula, and impedance spectroscopy characterization was performed via an intelligent LCR measuring instrument. Average grain sizes of PZT thin films were 60 nm~90 nm and their average roughness was less than 2 nm. According to X-ray diffraction analysis, 600°C is the optimal annealing temperature to obtain the PZT thin film with better crystallization. Average residual stress showed that thermal mismatch was the decisive factor of residual stress in Pt/Ti/SiO2/Si substrate; the residual stress in PZT thin film decreased as their thickness increased and increased with annealing temperature. The dielectric constant and loss angle tangent were extremely increased with the thickness of PZT thin films. The capacitance of the device can be adjusted according to the thickness of PZT thin films.

Optimum Operating Conditions for PZT Actuators for Vibrotactile Wearables

Science.gov (United States)

Logothetis, Irini; Matsouka, Dimitra; Vassiliadis, Savvas; Vossou, Clio; Siores, Elias

2018-04-01

Recently, vibrotactile wearables have received much attention in fields such as medicine, psychology, athletics and video gaming. The electrical components presently used to generate vibration are rigid; hence, the design and creation of ergonomical wearables are limited. Significant advances in piezoelectric components have led to the production of flexible actuators such as piezoceramic lead zirconate titanate (PZT) film. To verify the functionality of PZT actuators for use in vibrotactile wearables, the factors influencing the electromechanical conversion were analysed and tested. This was achieved through theoretical and experimental analyses of a monomorph clamped-free structure for the PZT actuator. The research performed for this article is a three-step process. First, a theoretical analysis presents the equations governing the actuator. In addition, the eigenfrequency of the film was analysed preceding the experimental section. For this stage, by applying an electric voltage and varying the stimulating electrical characteristics (i.e., voltage, electrical waveform and frequency), the optimum operating conditions for a PZT film were determined. The tip displacement was measured referring to the mechanical energy converted from electrical energy. From the results obtained, an equation for the mechanical behaviour of PZT films as actuators was deduced. It was observed that the square waveform generated larger tip displacements. In conjunction with large voltage inputs at the predetermined eigenfrequency, the optimum operating conditions for the actuator were achieved. To conclude, PZT films can be adapted to assist designers in creating comfortable vibrotactile wearables.

Ferroelectric capped magnetization in multiferroic PZT/LSMO tunnel junctions

Energy Technology Data Exchange (ETDEWEB)

Kumar, Ashok, E-mail: ashok553@nplindia.org; Shukla, A. K. [National Physical Laboratory (CSIR), Dr. K. S. Krishnan Road, New Delhi-110012 (India); Barrionuevo, D.; Ortega, N.; Katiyar, Ram S. [Department of Physics and Institute of Functional Nanomaterials, University of Puerto Rico, San Juan, Puerto Rico 00931-3343 (United States); Shannigrahi, Santiranjan [Institute of Materials Research and Engineering - IMRE, Agency for Science Technology and Research (A-STAR), 3 Research Link, Singapore 117602 (Singapore); Scott, J. F. [Department of Chemistry and Department of Physics, University of St. Andrews, St. Andrews KY16 ST (United Kingdom)

2015-03-30

Self-poled ultra-thin ferroelectric PbZr{sub 0.52}Ti{sub 0.48}O{sub 3} (PZT) (5 and 7 nm) films have been grown by pulsed laser deposition technique on ferromagnetic La{sub 0.67}Sr{sub 0.33}MnO{sub 3} (LSMO) (30 nm) to check the effect of polar capping on magnetization for ferroelectric tunnel junction devices. PZT/LSMO heterostructures with thick polar PZT (7 nm) capping show nearly 100% enhancement in magnetization compared with thin polar PZT (5 nm) films, probably due to excess hole transfer from the ferroelectric to the ferromagnetic layers. Core-level x-ray photoelectron spectroscopy studies revealed the presence of larger Mn 3s exchange splitting and higher Mn{sup 3+}/Mn{sup 4+} ion ratio in the LSMO with 7 nm polar capping.

Sensing capabilities of piezoelectric wafer active sensors in extreme nuclear environment

Science.gov (United States)

Faisal Haider, Mohammad; Lin, Bin; Yu, Lingyu; Giurgiutiu, Victor

2017-04-01

There is considerable demand for structural health monitoring (SHM) at locations where there are substantial radiation fields such as nuclear reactor components, dry cask storage canister, irradiated fuel assemblies, etc. Piezoelectric wafer active sensors (PWAS) have been emerged as one of the major SHM sensing technologies. In order to use PWAS to perform SHM in nuclear environment, radiation influence on sensor and sensing capability needs to be investigated to assure the reliability of the PWAS based method. Radiation may cause degradation or even complete failure of sensors. Gamma radiation is one of the major radiation sources near the nuclear source. Therefore, experimental investigation was completed on the gamma radiation endurance of piezoelectric sensors. The irradiation test was done in a Co-60 Gamma Irradiator. Lead Zirconate Titanate (PZT) and Gallium Orthophosphate (GaPO4) PWAS were exposed under gamma radiation at 100 Gy/hr rate for 20 hours. Electro-mechanical (E/M) admittance signatures and electrical capacitance were measured to evaluate the PWAS performance before and after every 4 hours exposure to gamma radiation. PWAS were kept at room temperature for 6 days after each 4 hours radiation exposure to investigate the effect of time on PWAS by gamma radiation. It was found that, PZT-PWAS show variation in resonance frequency for both in plane and thickness mode E/M admittance. Where, the changes in resonance amplitudes are larger for PZT-PWAS. GaPO4-PWAS E/M impedance/admittance spectra don't show any reasonable change after gamma irradiation. A degradation behavior of electrical properties in the PZT-PWAS was observed. Capacitance value of PZT-PWAS decreases from 3.2 nF to 3.07 nF after exposing to gamma radiation for 20 hours at 100Gy/hour. This degradation behavior of electrical properties may be explained by the pinning of domain walls by some radiation induced effect. GaPO4-PWAS doesn't show reasonable degradation in electrical properties

Packaging of active fiber composites for improved sensor performance

International Nuclear Information System (INIS)

Melnykowycz, M; Barbezat, M; Koller, R; Brunner, A J

2010-01-01

Active fiber composites (AFC) composed of lead zirconate titanate (PZT) fibers embedded in an epoxy matrix and sandwiched between two interdigitated electrodes provide a thin and flexible smart material device which can act as a sensor or actuator. The thin profiles of AFC make them ideal for integration in glass or carbon fiber composite laminates. However, due to the low tensile limit of the PZT fibers, AFC can fail at strains below the tensile limit of many composites. This makes their use as a component in an active laminate design somewhat undesirable. In the current work, tensile testing of smart laminates composed of AFC integrated in glass fiber laminates was conducted to assess the effectiveness of different packaging strategies for improving AFC sensor performance at high strains relative to the tensile limit of the AFC. AFC were encased in carbon fiber, silicon, and pre-stressed carbon fiber to improve the tensile limit of the AFC when integrated in glass fiber laminates. By laminating AFC with pre-stressed carbon fiber, the tensile limit and strain sensor ability of the AFC were significantly improved. Acoustic emission monitoring was used and the results show that PZT fiber breakage was reduced due to the pre-stressed packaging process

Piezoelectric and mechanical properties of structured PZT-epoxy composites

NARCIS (Netherlands)

James, N.K.; Ende, D.A. van den; Lafont, U.; Zwaag, S. van der; Groen, W.A.

2013-01-01

Structured lead zirconium titanate (PZT)-epoxy composites are prepared by dielectrophoresis. The piezoelectric and dielectric properties of the composites as a function of PZT volume fraction are investigated and compared with the corresponding unstructured composites. The effect of poling voltage

Nonlinear current-voltage behavior in PZT thin films

Energy Technology Data Exchange (ETDEWEB)

Xiao, Mi; Zhang, Weikang; Zhang, Zebin; Li, Shida; Zhang, Ping; Lan, Kuibo [Tianjin University, School of Electrical and Information Engineering, Tianjin (China)

2017-05-15

In this paper, Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3} (PZT) thin films were prepared by sol-gel synthesis and characterized by X-ray diffraction, field emission scanning electron microscopy and current-voltage measurements. Here, we demonstrate that in addition to the outstanding ferroelectric and dielectric properties, the PZT films also have remarkably nonlinear current-voltage characteristics. Considering the contact of semi-conductive grains in the PZT films, a double Schottky barrier (DSB) model may be responsible for such phenomena. The test results show that with the decrease of annealing temperature and the increase of the film thickness, the threshold voltages (V{sub th}) increase obviously. The maximum V{sub th} value of 60.95 V and the minimum value of 6.9 V in our experiments were obtained from the five-layered samples annealed at 600 C and the two-layered samples annealed at 700 C, respectively. As a result, PZT thin film may lead to efficient switching and sensing devices. (orig.)

Electric and ferroelectric properties of PZT/BLT multilayer films prepared by photochemical metal-organic deposition

Science.gov (United States)

Park, Hyeong-Ho; Lee, Hong-Sub; Park, Hyung-Ho; Hill, Ross H.; Hwang, Yun Taek

2009-01-01

The electric and ferroelectric properties of lead zirconate titanate (PZT) and lanthanum-substituted bismuth titanate (BLT) multilayer films prepared using photosensitive precursors were characterized. The electric and ferroelectric properties were investigated by studying the effect of the stacking order of four ferroelectric layers of PZT or BLT in 4-PZT, PZT/2-BLT/PZT, BLT/2-PZT/BLT, and 4-BLT multilayer films. The remnant polarization values of the 4-BLT and BLT/2-PZT/BLT multilayer films were 12 and 17 μC/cm 2, respectively. Improved ferroelectric properties of the PZT/BLT multilayer films were obtained by using a PZT intermediate layer. The films which contained a BLT layer on the Pt substrate had improved leakage currents of approximately two orders of magnitude and enhanced fatigue resistances compared to the films with a PZT layer on the Pt substrate. These improvements are due to the reduced number of defects and space charges near the Pt electrodes. The PZT/BLT multilayer films prepared by photochemical metal-organic deposition (PMOD) possessed enhanced electric and ferroelectric properties, and allow direct patterning to fabricate micro-patterned systems without dry etching.

Electric and ferroelectric properties of PZT/BLT multilayer films prepared by photochemical metal-organic deposition

International Nuclear Information System (INIS)

Park, Hyeong-Ho; Lee, Hong-Sub; Park, Hyung-Ho; Hill, Ross H.; Hwang, Yun Taek

2009-01-01

The electric and ferroelectric properties of lead zirconate titanate (PZT) and lanthanum-substituted bismuth titanate (BLT) multilayer films prepared using photosensitive precursors were characterized. The electric and ferroelectric properties were investigated by studying the effect of the stacking order of four ferroelectric layers of PZT or BLT in 4-PZT, PZT/2-BLT/PZT, BLT/2-PZT/BLT, and 4-BLT multilayer films. The remnant polarization values of the 4-BLT and BLT/2-PZT/BLT multilayer films were 12 and 17 μC/cm 2 , respectively. Improved ferroelectric properties of the PZT/BLT multilayer films were obtained by using a PZT intermediate layer. The films which contained a BLT layer on the Pt substrate had improved leakage currents of approximately two orders of magnitude and enhanced fatigue resistances compared to the films with a PZT layer on the Pt substrate. These improvements are due to the reduced number of defects and space charges near the Pt electrodes. The PZT/BLT multilayer films prepared by photochemical metal-organic deposition (PMOD) possessed enhanced electric and ferroelectric properties, and allow direct patterning to fabricate micro-patterned systems without dry etching.

Piezoelectric and mechanical properties of fatigue resistant, self-healing PZT-ionomer composites

NARCIS (Netherlands)

James, N.K.; Lafont, U.; Zwaag, S. van der; Groen, W.A.

2014-01-01

Piezoelectric ceramic-polymer composites with 0-3 connectivity were fabricated using lead zirconium titanate (PZT) powder dispersed in an ionomer (Zn ionomer) and its reference ethylene methacrylic acid copolymer (EMAA) polymer matrix. The PZT-Zn ionomer and PZT-EMAA composites were prepared by melt

Using piezoelectric sensors for ultrasonic pulse velocity measurements in concrete

International Nuclear Information System (INIS)

Kee, Seong-Hoon; Zhu, Jinying

2013-01-01

The ultrasonic pulse velocity (UPV) test has been a widely used non-destructive testing method for concrete structures. However, the conventional UPV test has limitations in consistency of results and applicability in hard-to-access regions of structures. The authors explore the feasibility of embedded piezoelectric (PZT) sensors for ultrasonic measurements in concrete structures. Two PZT sensors were embedded in a reinforced concrete specimen. One sensor worked as an actuator driven by an ultrasonic pulse-receiver, and another sensor worked as a receiver. A series of ultrasonic tests were conducted to investigate the performance of the embedded sensors in crack-free concrete and concrete specimens having a surface-breaking crack under various external loadings. Signals measured by the embedded sensors show a broad bandwidth with a centre frequency around 80 kHz, and very good coherence in the frequency range from 30 to 180 kHz. Furthermore, experimental variability in ultrasonic pulse velocity and attenuation is substantially reduced compared to previously reported values from conventional UPV equipment. Findings from this study demonstrate that the embedded sensors have great potential as a low-cost solution for ultrasonic transducers for health monitoring of concrete in structures. (paper)

Piezoelectric and mechanical properties of fatigue resistant, self-healing PZT-ionomer composites

Science.gov (United States)

James, N. K.; Lafont, U.; van der Zwaag, S.; Groen, W. A.

2014-05-01

Piezoelectric ceramic-polymer composites with 0-3 connectivity were fabricated using lead zirconium titanate (PZT) powder dispersed in an ionomer (Zn ionomer) and its reference ethylene methacrylic acid copolymer (EMAA) polymer matrix. The PZT-Zn ionomer and PZT-EMAA composites were prepared by melt extrusion followed by hot pressing. The effects of poling conditions such as temperature, time and electric field on the piezoelectric properties of the composites were investigated. The experimentally observed piezoelectric charge coefficient and dielectric constant of the composites were compared with theoretical models. The results show that PZT-Zn ionomer composites have better piezoelectric properties compared to PZT-EMAA composites. The static and fatigue properties of the composites were investigated. The PZT-Zn ionomer composites were found to have excellent fatigue resistance even at strain levels of 4%. Due to the self-healing capabilities of the ionomer matrix, the loss of piezoelectric properties after high strain tensile cyclic loading could be partially recovered by thermal healing.

Experimental research on dynamic mechanical properties of PZT ceramic under hydrostatic pressure

International Nuclear Information System (INIS)

Wang, S.; Liu, K.X.

2011-01-01

Highlights: → We developed an experimental device to examine dynamic mechanical properties of PZT. → Ductile behavior of PZT was seen when hydrostatic pressure was involved. → Compressive strength was shown sensitive to hydrostatic pressure and strain-rate. → A failure criterion was suggested to explain the failure behavior of PZT. - Abstract: An experimental technique for initially applied hydrostatic pressure in specimens subjected to axial impact has been developed to study the dynamic mechanical properties of materials. The technique was employed for the purpose of examining the dynamic mechanical properties of lead zirconate titanate (PZT) at zero to 15 MPa hydrostatic pressures. Experimental results unambiguously exhibit the ductile behavior of PZT when hydrostatic pressure is involved. The compressive strength is demonstrated sensitive to the initial hydrostatic pressure and the strain-rate. The fracture modes are analyzed by means of scanning electron microscopy (SEM). Moreover, a failure criterion based on Mohr-Coulomb failure theory is suggested to explain the brittle and ductile failure of PZT.

Nanocomposites with increased energy density through high aspect ratio PZT nanowires.

Science.gov (United States)

Tang, Haixiong; Lin, Yirong; Andrews, Clark; Sodano, Henry A

2011-01-07

High energy storage plays an important role in the modern electric industry. Herein, we investigated the role of filler aspect ratio in nanocomposites for energy storage. Nanocomposites were synthesized using lead zirconate titanate (PZT) with two different aspect ratio (nanowires, nanorods) fillers at various volume fractions dispersed in a polyvinylidene fluoride (PVDF) matrix. The permittivity constants of composites containing nanowires (NWs) were higher than those with nanorods (NRs) at the same inclusion volume fraction. It was also indicated that the high frequency loss tangent of samples with PZT nanowires was smaller than for those with nanorods, demonstrating the high electrical energy storage efficiency of the PZT NW nanocomposite. The high aspect ratio PZT NWs showed a 77.8% increase in energy density over the lower aspect ratio PZT NRs, under an electric field of 15 kV mm(-1) and 50% volume fraction. The breakdown strength was found to decrease with the increasing volume fraction of PZT NWs, but to only change slightly from a volume fraction of around 20%-50%. The maximum calculated energy density of nanocomposites is as high as 1.158 J cm(-3) at 50% PZT NWs in PVDF. Since the breakdown strength is lower compared to a PVDF copolymer such as poly(vinylidene fluoride-tertrifluoroethylene-terchlorotrifluoroethylene) P(VDF-TreEE-CTFE) and poly(vinylidene fluoride-co-hexafluoropropylene) P(VDF-HFP), the energy density of the nanocomposite could be significantly increased through the use of PZT NWs and a polymer with greater breakdown strength. These results indicate that higher aspect ratio fillers show promising potential to improve the energy density of nanocomposites, leading to the development of advanced capacitors with high energy density.

PMN-PT-PZT composite films for high frequency ultrasonic transducer applications.

Science.gov (United States)

Hsu, Hsiu-Sheng; Benjauthrit, Vatcharee; Zheng, Fan; Chen, Rumin; Huang, Yuhong; Zhou, Qifa; Shung, K Kirk

2012-06-01

We have successfully fabricated x (0.65PMN-0.35PT)-(1 - x )PZT ( x PMN-PT-(1 - x )PZT), where x is 0.1, 0.3, 0.5, 0.7 and 0.9, thick films with a thickness of approximately 9 µm on platinized silicon substrate by employing a composite sol-gel technique. X-ray diffraction analysis and scanning electron microscopy revealed that these films are dense and creak-free with well-crystallized perovskite phase in the whole composition range. The dielectric constant can be controllably adjusted by using different compositions. Higher PZT content of x PMN-PT-(1 - x )PZT films show better ferroelectric properties. A representative 0.9PMN-PT-0.1PZT thick film transducer is built. It has 200 MHz center frequency with a -6 dB bandwidth of 38% (76 MHz). The measured two-way insertion loss is 65 dB.

The effects of sintering behavior on piezoelectric properties of porous PZT ceramics for hydrophone application

International Nuclear Information System (INIS)

Zeng Tao; Dong Xianlin; Chen Heng; Wang Yonglin

2006-01-01

Porous lead zirconate titanate (PZT) ceramics were fabricated by adding polymethyl methacrylate (PMMA) and the effects of sintering behavior on their microstructure and piezoelectric properties were investigated. The porosity of PZT ceramics decreased with an increase in the sintering temperature at a fixed PMMA addition. The dielectric constant (ε), longitudinal piezoelectric coefficient (d 33 ) and hydrostatic figures of merit (d h g h ) of 34% porous PZT ceramics increased with an increase in sintering temperature from 1050 to 1300 deg. C. When sintered at 1300 deg. C, longitudinal piezoelectric coefficient of 34% porous PZT ceramic was very close to that of 95% dense PZT ceramics, while the hydrostatic figures of merit of 34% porous PZT ceramics is about fifteen times more than that of 95% dense PZT ceramics. Compared with PZT-polymer composites, the dielectric constant of 34% porous PZT sintered at 1300 deg. C is much higher, which can be more efficient to resist the interference in receiving sensitivities caused by loading effect of the cable

Characterization of Bi and Fe co-doped PZT capacitors for FeRAM.

Science.gov (United States)

Cross, Jeffrey S; Kim, Seung-Hyun; Wada, Satoshi; Chatterjee, Abhijit

2010-08-01

Ferroelectric random access memory (FeRAM) has been in mass production for over 15 years. Higher polarization ferroelectric materials are needed for future devices which can operate above about 100 °C. With this goal in mind, co-doping of thin Pb(Zr 40 ,Ti 60 )O 3 (PZT) films with 1 at.% Bi and 1 at.% Fe was examined in order to enhance the ferroelectric properties as well as characterize the doped material. The XRD patterns of PZT-5% BiFeO 3 (BF) and PZT 140-nm thick films showed (111) orientation on (111) platinized Si wafers and a 30 °C increase in the tetragonal to cubic phase transition temperature, often called the Curie temperature, from 350 to 380 °C with co-doping, indicating that Bi and Fe are substituting into the PZT lattice. Raman spectra revealed decreased band intensity with Bi and Fe co-doping of PZT compared to PZT. Polarization hysteresis loops show similar values of remanent polarization, but square-shaped voltage pulse-measured net polarization values of PZT-BF were higher and showed higher endurance to repeated cycling up to 10 10 cycles. It is proposed that Bi and Fe are both in the +3 oxidation state and substituting into the perovskite A and B sites, respectively. Substitution of Bi and Fe into the PZT lattice likely creates defect dipoles, which increase the net polarization when measured by the short voltage pulse positive-up-negative-down (PUND) method.

Uncertainty quantification for PZT bimorph actuators

Science.gov (United States)

Bravo, Nikolas; Smith, Ralph C.; Crews, John

2018-03-01

In this paper, we discuss the development of a high fidelity model for a PZT bimorph actuator used for micro-air vehicles, which includes the Robobee. We developed a high-fidelity model for the actuator using the homogenized energy model (HEM) framework, which quantifies the nonlinear, hysteretic, and rate-dependent behavior inherent to PZT in dynamic operating regimes. We then discussed an inverse problem on the model. We included local and global sensitivity analysis of the parameters in the high-fidelity model. Finally, we will discuss the results of Bayesian inference and uncertainty quantification on the HEM.

PZT/PLZT - elastomer composites with improved piezoelectric voltage coefficient

Science.gov (United States)

Harikrishnan, K.; Bavbande, D. V.; Mohan, Dhirendra; Manoharan, B.; Prasad, M. R. S.; Kalyanakrishnan, G.

2018-02-01

Lead Zirconate Titanate (PZT) and Lanthanum-modified Lead Zirconate Titanate (PLZT) ceramic sensor materials are widely used because of their excellent piezoelectric coefficients. These materials are brittle, high density and have low achievable piezoelectric voltage coefficients. The density of the sintered ceramics shall be reduced by burnable polymeric sponge method. The achievable porosity level in this case is nearly 60 - 90%. However, the porous ceramic structure with 3-3 connectivity produced by this method is very fragile in nature. The strength of the porous structure is improved with Sylgard®-184 (silicone elastomer) by vacuum impregnation method maintaining the dynamic vacuum level in the range of -650 mm Hg. The elastomer Sylgard®-184 is having low density, low dielectric constant and high compliance (as a resultant stiffness of the composites is increased). To obtain a net dipole moment, the impregnated ceramic composites were subjected to poling treatment with varying conditions of D.C. field and temperature. The properties of the poled PZT/PLZT - elastomer composites were characterized with LCR meter for measuring the dielectric constant values (k), d33 meter used for measuring piezo-electric charge coefficient values (d33) and piezo-electric voltage coefficient (g33) values which were derived from d33 values. The voltage coefficient (g33) values of these composites are increased by 10 fold as compared to the conventional solid ceramics demonstrates that it is possible to fabricate a conformable detector.

Magnetoelectric coupling in layered LSMO/PZT nanostructures

International Nuclear Information System (INIS)

Leufke, Philipp M.

2014-01-01

Multiferroic thin film composites with electric field-effect driven magnetoelectric (ME) coupling offer the possibility to reversibly tune magnetic properties in materials intended for device applications. The structural and functional versatility of such artificial heterostructures makes them attractive not only for various data processing, storage and sensor applications but also for studying the fundamental ME coupling mechanisms. La 1-x Sr x MnO 3 (LSMO)/PbZr y Ti 1-y O 3 (PZT) is an ideal choice for such a composite, combining the unrivaled ferroelectric (FE) properties of PZT with the multiple electronic and magnetic phenomena exhibited by the mixed valency manganite LSMO. The main physical feature used in realization of the LSMO/PZT ME composites is a striking sensitivity of LSMO magnetism to the charge carrier density. Here, the low-doping region is of particular interest, where the competition between the fundamental magnetic coupling mechanisms, Double-Exchange (DE) versus Superexchange (SE), is most distinctive. In the present work an unconventional sputtering technique - the Large-Distance Magnetron Sputtering (LDMS) method - has been established, which allowed for epitaxial deposition of these heterostructures with highest crystallinity and markedly smooth interfaces, necessary for effective field-effect control of magnetism. The large target-substrate distance effectively suppressed the destructive oxygen ion bombardment, inherently connected with oxide sputtering, and yielded an outstanding lateral uniformity of the film stack. The latter was vital for the fabrication of large capacitor structures of several square millimeter area that were required for detecting the ME coupling in a Superconductive Quantum Interference Device (SQUID) magnetometer. The growth of LSMO on various single crystalline substrates was mastered by exploring a vast deposition parameter space, encompassing Radio Frequency (RF) and Direct Current (DC) sputtering. Commensurately

Magnetoelectric coupling in layered LSMO/PZT nanostructures

Energy Technology Data Exchange (ETDEWEB)

Leufke, Philipp M.

2014-01-29

Multiferroic thin film composites with electric field-effect driven magnetoelectric (ME) coupling offer the possibility to reversibly tune magnetic properties in materials intended for device applications. The structural and functional versatility of such artificial heterostructures makes them attractive not only for various data processing, storage and sensor applications but also for studying the fundamental ME coupling mechanisms. La{sub 1-x}Sr{sub x}MnO{sub 3} (LSMO)/PbZr{sub y}Ti{sub 1-y}O{sub 3} (PZT) is an ideal choice for such a composite, combining the unrivaled ferroelectric (FE) properties of PZT with the multiple electronic and magnetic phenomena exhibited by the mixed valency manganite LSMO. The main physical feature used in realization of the LSMO/PZT ME composites is a striking sensitivity of LSMO magnetism to the charge carrier density. Here, the low-doping region is of particular interest, where the competition between the fundamental magnetic coupling mechanisms, Double-Exchange (DE) versus Superexchange (SE), is most distinctive. In the present work an unconventional sputtering technique - the Large-Distance Magnetron Sputtering (LDMS) method - has been established, which allowed for epitaxial deposition of these heterostructures with highest crystallinity and markedly smooth interfaces, necessary for effective field-effect control of magnetism. The large target-substrate distance effectively suppressed the destructive oxygen ion bombardment, inherently connected with oxide sputtering, and yielded an outstanding lateral uniformity of the film stack. The latter was vital for the fabrication of large capacitor structures of several square millimeter area that were required for detecting the ME coupling in a Superconductive Quantum Interference Device (SQUID) magnetometer. The growth of LSMO on various single crystalline substrates was mastered by exploring a vast deposition parameter space, encompassing Radio Frequency (RF) and Direct Current (DC

Effects of Mn doping on the ferroelectric properties of PZT thin films

International Nuclear Information System (INIS)

Zhang Qi

2004-01-01

The effects of Mn doping on the ferroelectric properties of Pb(Zr 0.3 Ti 0.7 )O 3 (PZT) thin films on Pt/Ti/SiO 2 /Si substrates have been investigated. The composition of the PZT and Mn doping level are Pb(Zr 0.3 Ti 0.7 ) 1-x Mn x O 3 (x = 0,0.2,0.5,1,2,4 mol%). The PZT thin films doped with a small amount of Mn 2+ (x ≤ 1) showed almost no hysteretic fatigue up to 10 10 switching bipolar pulse cycles, coupled with excellent retention properties. However, excessive additions of manganese made the fatigue behaviour worse. We propose that the addition of small amounts of Mn is able to reduce the oxygen vacancy concentration due to the combination of Mn 2+ and oxygen vacancies in PZT films, forming Mn 4+ ions. The interfacial layer between the Pt electrode and PZT films and Mn-doped PZT (x = 4) was detected by measuring the dielectric constant of thin films of different thickness. However, this interfacial layer was not detected in Mn-doped PZT (x = 1). These observations support the concept of the preferential electromigration of oxygen vacancies into sites in planes parallel to the electrodes, which is probably responsible for the hysteretic fatigue

PMN-PT–PZT composite films for high frequency ultrasonic transducer applications

Science.gov (United States)

Hsu, Hsiu-Sheng; Benjauthrit, Vatcharee; Zheng, Fan; Chen, Rumin; Huang, Yuhong; Zhou, Qifa; Shung, K. Kirk

2013-01-01

We have successfully fabricated x(0.65PMN-0.35PT)–(1 − x)PZT (xPMN-PT–(1 − x)PZT), where x is 0.1, 0.3, 0.5, 0.7 and 0.9, thick films with a thickness of approximately 9 µm on platinized silicon substrate by employing a composite sol–gel technique. X-ray diffraction analysis and scanning electron microscopy revealed that these films are dense and creak-free with well-crystallized perovskite phase in the whole composition range. The dielectric constant can be controllably adjusted by using different compositions. Higher PZT content of xPMN-PT–(1 − x)PZT films show better ferroelectric properties. A representative 0.9PMN-PT–0.1PZT thick film transducer is built. It has 200 MHz center frequency with a −6 dB bandwidth of 38% (76 MHz). The measured two-way insertion loss is 65 dB. PMID:23750072

Properties of PZT-Based Piezoelectric Ceramics Between -150 and 250 C

Science.gov (United States)

Hooker, Matthew W.

1998-01-01

The properties of three PZT-based piezoelectric ceramics and one PLZT electrostrictive ceramic were measured as a function of temperature. In this work, the dielectric, ferroelectric polarization versus electric field, and piezoelectric properties of PZT-4, PZT-5A, PZT-5H, and PLZT-9/65/35 were measured over a temperature range of -150 to 250 C. In addition to these measurements, the relative thermal expansion of each composition was measured from 25 to 600 C and the modulus of rupture of each material was measured at room temperature. This report describes the experimental results and compares and contrasts the properties of these materials with respect to their applicability to intelligent aerospace systems.

Microscopic local fatigue in PZT thin films

International Nuclear Information System (INIS)

Li, B S; Wu, A; Vilarinho, P M

2007-01-01

The reduction in switchable polarization during fatigue largely limits the application of PZT thin films in ferroelectric nonvolatile memories. So, it is very important to understand the fatigue mechanism in PZT films, especially at a nanoscale level. In this paper, nanoscale fatigue properties in PZT thin films have been studied by piezoresponse force microscopy and local piezoloops. It has been found that a piezoloop obtained on a fatigued point exhibits a much more pinched shape and a local imprint phenomenon is observed after severe fatigue. Furthermore, the domain structure evolves from a simple single-peak profile to a complex fluctuant one. However, there is only some shift of the piezoloop when a unipolar field with the same amplitude is applied on the film. The available experimental data show that there exist obvious domain wall pinning and injection of electrons into the film during fatigue. Finally, a schematic illustration is suggested to explain the possible fatigue mechanism

Synthesis, Structural, Optical and Dielectric Properties of Nanostructured 0-3 PZT/PVDF Composite Films.

Science.gov (United States)

Revathi, S; Kennedy, L John; Basha, S K Khadheer; Padmanabhan, R

2018-07-01

Nanostructured PbZr0.52Ti0.48O3 (PZT) powder was synthesized at 500 °C-800 °C using sol-gel route. X-ray diffraction and Rietveld analysis confirmed the formation of perovskite structure. The sample heat treated at 800 °C alone showed the formation of morphotropic phase boundary with coexistence of tetragonal and rhombohedral phase. The PZT powder and PVDF were used in 0-3 connectivity to form the PZT/PVDF composite film using solvent casting method. The composite films containing 10%, 50%, 70% and 80% volume fraction of PZT in PVDF were fabricated. The XRD spectra validated that the PZT structure remains unaltered in the composites and was not affected by the presence of PVDF. The scanning electron microscopy images show good degree of dispersion of PZT in PVDF matrix and the formation of pores at higher PZT loading. The quantitative analysis of elements and their composition were confirmed from energy dispersive X-ray analysis. The optical band gap of the PVDF film is 3.3 eV and the band gap decreased with increase in volume fraction of PZT fillers. The FTIR spectra showed the bands corresponding to different phases of PVDF (α, β, γ) and perovskite phase of PZT. The thermogravimetric analysis showed that PZT/PVDF composite films showed better thermal stability than the pure PVDF film and hydrophobicity. The dielectric constant was measured at frequency ranging from 1 Hz to 6 MHz and for temperature ranging from room temperature to 150 °C. The composite with 50% PZT filler loading shows the maximum dielectric constant at the studied frequency and temperature range with flexibility.

Conventional and two step sintering of PZT-PCN ceramics

Science.gov (United States)

Keshavarzi, Mostafa; Rahmani, Hooman; Nemati, Ali; Hashemi, Mahdieh

2018-02-01

In this study, PZT-PCN ceramic was made via sol-gel seeding method and effects of conventional sintering (CS) as well as two-step sintering (TSS) were investigated on microstructure, phase formation, density, dielectric and piezoelectric properties. First, high quality powder was achieved by seeding method in which the mixture of Co3O4 and Nb2O5 powder was added to the prepared PZT sol to form PZT-PCN gel. After drying and calcination, pyrochlore free PZT-PCN powder was synthesized. Second, CS and TSS were applied to achieve dense ceramic. The optimum temperature used for 2 h of conventional sintering was obtained at 1150 °C; finally, undesired ZrO2 phase formed in CS procedure was removed successfully with TSS procedure and dielectric and piezoelectric properties were improved compared to the CS procedure. The best electrical properties obtained for the sample sintered by TSS in the initial temperature of T 1 = 1200 °C and secondary temperature of T 2 = 1000 °C for 12 h.

Pyroelectricity versus conductivity in soft lead zirconate titanate (PZT) ceramics

NARCIS (Netherlands)

Kamel, T.M.; With, de G.

2007-01-01

The electrical behavior of modified soft lead zirconate titanate (PZT) ceramics has been studied as a function of temperature at different direct current (dc) electric fields and grain sizes. As ferroelectrics, such as PZT, are highly polarizable materials, poling, depolarization, and electric

Dielectric and acoustical high frequency characterisation of PZT thin films

International Nuclear Information System (INIS)

Conde, Janine; Muralt, Paul

2010-01-01

Pb(Zr, Ti)O 3 (PZT) is an interesting material for bulk acoustic wave resonator applications due to its high electromechanical coupling constant, which would enable fabrication of large bandwidth frequency filters. The major challenge of the PZT solid solution system is to overcome mechanical losses generally observed in PZT ceramics. To increase the understanding of these losses in textured thin films, thin film bulk acoustic resonators (TFBAR's) based on PZT thin films with compositions either in the tetragonal region or at the morphotropic phase boundary and (111) or {100} textures were fabricated and studied up to 2 GHz. The dielectric and elastic materials coefficients were extracted from impedance measurements at the resonance frequency. The dispersion of the dielectric constant was obtained from impedance measurements up to 2 GHz. The films with varying compositions, textures and deposition methods (sol-gel or sputtering) were compared in terms of dielectric and acoustical properties.

Dielectric and acoustical high frequency characterisation of PZT thin films

Science.gov (United States)

Conde, Janine; Muralt, Paul

2010-02-01

Pb(Zr, Ti)O3 (PZT) is an interesting material for bulk acoustic wave resonator applications due to its high electromechanical coupling constant, which would enable fabrication of large bandwidth frequency filters. The major challenge of the PZT solid solution system is to overcome mechanical losses generally observed in PZT ceramics. To increase the understanding of these losses in textured thin films, thin film bulk acoustic resonators (TFBAR's) based on PZT thin films with compositions either in the tetragonal region or at the morphotropic phase boundary and (111) or {100} textures were fabricated and studied up to 2 GHz. The dielectric and elastic materials coefficients were extracted from impedance measurements at the resonance frequency. The dispersion of the dielectric constant was obtained from impedance measurements up to 2 GHz. The films with varying compositions, textures and deposition methods (sol-gel or sputtering) were compared in terms of dielectric and acoustical properties.

Highly-efficient, flexible piezoelectric PZT thin film nanogenerator on plastic substrates.

Science.gov (United States)

Park, Kwi-Il; Son, Jung Hwan; Hwang, Geon-Tae; Jeong, Chang Kyu; Ryu, Jungho; Koo, Min; Choi, Insung; Lee, Seung Hyun; Byun, Myunghwan; Wang, Zhong Lin; Lee, Keon Jae

2014-04-23

A highly-efficient, flexible piezoelectric PZT thin film nanogenerator is demonstrated using a laser lift-off (LLO) process. The PZT thin film nanogenerator harvests the highest output performance of ∼200 V and ∼150 μA·cm(-2) from regular bending motions. Furthermore, power sources generated from a PZT thin film nanogenerator, driven by slight human finger bending motions, successfully operate over 100 LEDs. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Antiferrodistortive phase transitions and ground state of PZT ceramics

International Nuclear Information System (INIS)

Pandey, Dhananjai

2013-01-01

The ground state of the technologically important Pb(Zr x Ti (1-x) )O 3 , commonly known as PZT, ceramics is currently under intense debate. The phase diagram of this material shows a morphotropic phase boundary (MPB) for x∼0.52 at 300K, across which a composition induced structural phase transition occurs leading to maximization of the piezoelectric properties. In search for the true ground state of the PZT in the MPB region, Beatrix Noheda and coworkers first discovered a phase transition from tetragonal (space group P4mm) to an M A type monoclinic phase (space group Cm) at low temperatures for x=0.52. Soon afterwards, we discovered yet another low temperature phase transition for the same composition in which the M A type (Cm) monoclinic phase transforms to another monoclinic phase with Cc space group. We have shown that the Cm to Cc phase transition is an antiferrodistortive (AFD) transition involving tilting of oxygen octahedra leading to unit cell doubling and causing appearance of superlattice reflections which are observable in the electron and neutron diffraction patterns only and not in the XRD patterns, as a result of which Noheda and coworkers missed the Cc phase in their synchrotron XRD studies at low temperatures. Our findings were confirmed by leading groups using neutron, TEM, Raman and high pressure diffraction studies. The first principles calculations also confirmed that the true ground state of PZT in the MPB region has Cc space group. However, in the last couple of years, the Cc space group of the ground state has become controversial with an alternative proposal of R3c as the space group of the ground state phase which is proposed to coexist with the metastable Cm phase. In order to resolve this controversy, we recently revisited the issue using pure PZT and 6% Sr 2+ substituted PZT, the latter samples show larger tilt angle on account of the reduction in the average cationic radius at the Pb 2+ site. Using high wavelength neutrons and high

Micro-machined high-frequency (80 MHz) PZT thick film linear arrays.

Science.gov (United States)

Zhou, Qifa; Wu, Dawei; Liu, Changgeng; Zhu, Benpeng; Djuth, Frank; Shung, K

2010-10-01

This paper presents the development of a micromachined high-frequency linear array using PZT piezoelectric thick films. The linear array has 32 elements with an element width of 24 μm and an element length of 4 mm. Array elements were fabricated by deep reactive ion etching of PZT thick films, which were prepared from spin-coating of PZT sol-gel composite. Detailed fabrication processes, especially PZT thick film etching conditions and a novel transferring-and-etching method, are presented and discussed. Array designs were evaluated by simulation. Experimental measurements show that the array had a center frequency of 80 MHz and a fractional bandwidth (-6 dB) of 60%. An insertion loss of -41 dB and adjacent element crosstalk of -21 dB were found at the center frequency.

Dielectric and acoustical high frequency characterisation of PZT thin films

Energy Technology Data Exchange (ETDEWEB)

Conde, Janine; Muralt, Paul, E-mail: janine.conde@epfl.ch [Department of Materials Science, EPFL (Switzerland)

2010-02-15

Pb(Zr, Ti)O{sub 3} (PZT) is an interesting material for bulk acoustic wave resonator applications due to its high electromechanical coupling constant, which would enable fabrication of large bandwidth frequency filters. The major challenge of the PZT solid solution system is to overcome mechanical losses generally observed in PZT ceramics. To increase the understanding of these losses in textured thin films, thin film bulk acoustic resonators (TFBAR's) based on PZT thin films with compositions either in the tetragonal region or at the morphotropic phase boundary and (111) or {l_brace}100{r_brace} textures were fabricated and studied up to 2 GHz. The dielectric and elastic materials coefficients were extracted from impedance measurements at the resonance frequency. The dispersion of the dielectric constant was obtained from impedance measurements up to 2 GHz. The films with varying compositions, textures and deposition methods (sol-gel or sputtering) were compared in terms of dielectric and acoustical properties.

Impedance-Based Cable Force Monitoring in Tendon-Anchorage Using Portable PZT-Interface Technique

Directory of Open Access Journals (Sweden)

Thanh-Canh Huynh

2014-01-01

Full Text Available In this paper, a portable PZT interface for tension force monitoring in the cable-anchorage subsystem is developed. Firstly, the theoretical background of the impedance-based method is presented. A few damage evaluation approaches are outlined to quantify the variation of impedance signatures. Secondly, a portable PZT interface is designed to monitor impedance signatures from the cable-anchorage subsystem. One degree-of-freedom analytical model of the PZT interface is established to explain how to represent the loss of cable force from the change in the electromechanical impedance of the PZT interface as well as reducing the sensitive frequency band by implementing the interface device. Finally, the applicability of the proposed PZT-interface technique is experimentally evaluated for cable force-loss monitoring in a lab-scaled test structure.

Effect of Nb doping on sintering and dielectric properties of PZT ceramics

Directory of Open Access Journals (Sweden)

Ali Mirzaei

2016-09-01

Full Text Available The extensive use of piezoelectric ceramics such as lead zirconate titanate (PZT in different applications became possible with the development of donor or acceptor dopants. Therefore, studies on the effect of dopants on the properties of PZT ceramics are highly demanded. In this study undoped and 2.4 mol% Nb-doped PZT (PZTN powders were successfully obtained by a solid-state reaction and calcination at 850 °C for 2 h. Crystallinity and phase formation of the prepared powders were studied using X-ray diffraction (XRD. In order to study morphology of powders, scanning electron microscopy (SEM was performed. The crystalline PZT and Nb-doped PZT powders were pelleted into discs and sintered at 1100, 1150 and 1200 °C, with a heating rate of 10 °C/min, and holding time of 1–6 h to find the optimum combination of temperature and time to produce high density ceramics. Microstructural characterization was conducted on the fractured ceramic surfaces using SEM. Density measurements showed that maximal density of 95% of the theoretical density was achieved after sintering of PZT and PZTN ceramics at 1200 °C for 2 h and 4 h, respectively. However, the results of dielectric measurements showed that PZTN ceramics have higher relative permittivity (εr ∼17960 with lower Curie temperature (∼358 °C relative to PZT (εr = 16000 at ∼363 °C as a result of fine PZTN structure as well as presence of vacancies. In addition, dielectric loss (at 1 kHz of PZT and PZTN ceramics with 95% theoretical density was 0.0087 and 0.02, respectively. The higher dielectric loss in PZTN was due to easier domain wall motions in PZTN ceramics.

MEMS-based thick film PZT vibrational energy harvester

DEFF Research Database (Denmark)

Lei, Anders; Xu, Ruichao; Thyssen, Anders

2011-01-01

We present a MEMS-based unimorph silicon/PZT thick film vibrational energy harvester with an integrated proof mass. We have developed a process that allows fabrication of high performance silicon based energy harvesters with a yield higher than 90%. The process comprises a KOH etch using a mechan......We present a MEMS-based unimorph silicon/PZT thick film vibrational energy harvester with an integrated proof mass. We have developed a process that allows fabrication of high performance silicon based energy harvesters with a yield higher than 90%. The process comprises a KOH etch using...... a mechanical front side protection of an SOI wafer with screen printed PZT thick film. The fabricated harvester device produces 14.0 μW with an optimal resistive load of 100 kΩ from 1g (g=9.81 m s-2) input acceleration at its resonant frequency of 235 Hz....

Mechanically activated synthesis of PZT and its electromechanical properties

Energy Technology Data Exchange (ETDEWEB)

Liu, X.; Akdogan, E.K.; Safari, A.; Riman, R.E. [Rutgers the State University of New Jersey, Department of Ceramic and Materials Engineering, Piscataway, NJ (United States)

2005-08-01

Mechanical activation was successfully used to synthesize nanostructured phase-pure Pb(Zr{sub 0.7}Ti{sub 0.3})O{sub 3} (PZT) powders. Lead-zirconium-titanium (PbZrTi) hydrous oxide precursor, synthesized from chemical co-precipitation, was mechanically activated in a NaCl matrix. The synthesized PZT particles were characterized by using X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, laser-light diffraction, and nitrogen adsorption. Thermogravimetric analysis and differential thermal analysis were used to monitor dehydration and phase transformation of PbZrTi hydrous oxide precursor during mechanical activation. The best mechanical activation conditions corresponded to mechanically activating PbZrTi hydrous oxide precursor in a NaCl matrix with a NaCl/precursor weight ratio of 4:1 for 8 h. These conditions resulted in a dispersible phase-pure PZT powder with a median secondary-particle size of {proportional_to}110 nm. The properties of PZT 70/30 from mechanically activated powder, as measured on discs sintered at 1150 C for 2 h, were found to be in close conformity to those obtained by a conventional mixed oxide solid state reaction route. (orig.)

Mechanically activated synthesis of PZT and its electromechanical properties

Science.gov (United States)

Liu, X.; Akdogan, E. K.; Safari, A.; Riman, R. E.

2005-08-01

Mechanical activation was successfully used to synthesize nanostructured phase-pure Pb(Zr0.7Ti0.3)O3 (PZT) powders. Lead zirconium titanium (PbZrTi) hydrous oxide precursor, synthesized from chemical co-precipitation, was mechanically activated in a NaCl matrix. The synthesized PZT particles were characterized by using X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, laser-light diffraction, and nitrogen adsorption. Thermogravimetric analysis and differential thermal analysis were used to monitor dehydration and phase transformation of PbZrTi hydrous oxide precursor during mechanical activation. The best mechanical activation conditions corresponded to mechanically activating PbZrTi hydrous oxide precursor in a NaCl matrix with a NaCl/precursor weight ratio of 4:1 for 8 h. These conditions resulted in a dispersible phase-pure PZT powder with a median secondary-particle size of ˜110 nm. The properties of PZT 70/30 from mechanically activated powder, as measured on discs sintered at 1150 °C for 2 h, were found to be in close conformity to those obtained by a conventional mixed oxide solid state reaction route.

Effect of External Vibration on PZT Impedance Signature

Directory of Open Access Journals (Sweden)

Yaowen Yang

2008-11-01

Full Text Available Piezoelectric ceramic Lead Zirconate Titanate (PZT transducers, working on the principle of electromechanical impedance (EMI, are increasingly applied for structural health monitoring (SHM in aerospace, civil and mechanical engineering. The PZT transducers are usually surface bonded to or embedded in a structure and subjected to actuation so as to interrogate the structure at the desired frequency range. The interrogation results in the electromechanical admittance (inverse of EMI signatures which can be used to estimate the structural health or integrity according to the changes of the signatures. In the existing EMI method, the monitored structure is only excited by the PZT transducers for the interrogating of EMI signature, while the vibration of the structure caused by the external excitations other than the PZT actuation is not considered. However, many structures work under vibrations in practice. To monitor such structures, issues related to the effects of vibration on the EMI signature need to be addressed because these effects may lead to misinterpretation of the structural health. This paper develops an EMI model for beam structures, which takes into account the effect of beam vibration caused by the external excitations. An experimental study is carried out to verify the theoretical model. A lab size specimen with different external excitations is tested and the effect of vibration on EMI signature is discussed.

Effect of External Vibration on PZT Impedance Signature.

Science.gov (United States)

Yang, Yaowen; Miao, Aiwei

2008-11-01

Piezoelectric ceramic Lead Zirconate Titanate (PZT) transducers, working on the principle of electromechanical impedance (EMI), are increasingly applied for structural health monitoring (SHM) in aerospace, civil and mechanical engineering. The PZT transducers are usually surface bonded to or embedded in a structure and subjected to actuation so as to interrogate the structure at the desired frequency range. The interrogation results in the electromechanical admittance (inverse of EMI) signatures which can be used to estimate the structural health or integrity according to the changes of the signatures. In the existing EMI method, the monitored structure is only excited by the PZT transducers for the interrogating of EMI signature, while the vibration of the structure caused by the external excitations other than the PZT actuation is not considered. However, many structures work under vibrations in practice. To monitor such structures, issues related to the effects of vibration on the EMI signature need to be addressed because these effects may lead to misinterpretation of the structural health. This paper develops an EMI model for beam structures, which takes into account the effect of beam vibration caused by the external excitations. An experimental study is carried out to verify the theoretical model. A lab size specimen with different external excitations is tested and the effect of vibration on EMI signature is discussed.

Enhanced Output Power of PZT Nanogenerator by Controlling Surface Morphology of Electrode.

Science.gov (United States)

Jung, Woo-Suk; Lee, Won-Hee; Ju, Byeong-Kwon; Yoon, Seok-Jin; Kang, Chong-Yun

2015-11-01

Piezoelectric power generation using Pb(Zr,Ti)O3(PZT) nanowires grown on Nb-doped SrTiO3(nb:STO) substrate has been demonstrated. The epitaxial PZT nanowires prepared by a hydrothermal method, with a diameter and length of approximately 300 nm and 7 μm, respecively, were vertically aligned on the substrate. An embossed Au top electrode was applied to maximize the effective power generation area for non-uniform PZT nanowires. The PZT nanogenerator produced output power density of 0.56 μW/cm2 with a voltage of 0.9 V and current of 75 nA. This research suggests that the morphology control of top electrode can be useful to improve the efficiency of piezoelectric power generation.

Feasibility Verification of Mountable PZT-Interface for Impedance Monitoring in Tendon-Anchorage

Directory of Open Access Journals (Sweden)

Thanh-Canh Huynh

2015-01-01

Full Text Available This study has been motivated to numerically evaluate the performance of the mountable PZT-interface for impedance monitoring in tendon-anchorage. Firstly, electromechanical impedance monitoring and feature classification methods are outlined. Secondly, a structural model of tendon-anchorage subsystem with mountable PZT-interface is designed for impedance monitoring. Finally, the feasibility of the mountable PZT-interface is numerically examined. A finite element (FE model is designed for the lab-scaled tendon-anchorage. The FE model of the PZT-interface is tuned as its impedance signatures meet the experimental test results at the same frequency ranges and also with identical patterns. Equivalent model properties of the FE model corresponding to prestress forces inflicted on the lab-tested structure are identified from the fine-tuning practice.

Synthesis and characterization of tungsten or calcium doped PZT ceramics; Sintese e caracterizacao do PZT dopado com W ou Ca

Energy Technology Data Exchange (ETDEWEB)

Santos, D.M.; Caracas, L.B.; Noronha, R.G.; Santos, M.M.T. dos [Universidade Federal do Maranhao (UFMA), Sao Luis, MA (Brazil). Dept. de Desenho e Tecnologia. Curso de Desenho Industrial; Paiva-Santos, C.O., E-mail: denilson@ufma.b [Universidade Estadual Paulista (IQ/UNESP), Araraquara, SP (Brazil). Inst. de Quimica

2009-07-01

Pure and doped (tungsten or calcium) PZT ceramics were prepared by association of the polymeric precursor and partial oxalate method. The phase formation was investigated by thermal analysis (TG/DSC) and X-ray diffraction (XRD). The affect of W or Ca doping PZT and their electrical properties was evaluated. Substitution of W by Ti and Ca by Pb leads to an increase of Curie temperature and broadening of dielectric constant. A typical hysteresis loop was observed at room temperature and the remnant polarization was increased with the content of W and Ca. (author)

Characterization of PZT thin films on metal substrates

International Nuclear Information System (INIS)

Dutschke, A.

2008-01-01

Lead zirconate titanate (PbZr x Ti 1-x O 3 ,PZT) is one of the most applied ceramic materials because of its distinctive piezo- and ferroelectric properties. Prepared as thin films on flexible, metallic substrates it can be used for various applications as strain gauges, key switches, vibration dampers, microactuators and ultrasonic transducers. The aim of this work is to analyze the microstructure and the phase-content of PZT-thin films deposited on temperature- und acid-resistant hastelloy-sheets, to correlate the results with the ferroelectric and dielectric properties. It is demonstrated, that the specific variation of the microstructure can be achieved by different thermal treatments and the selective addition of Neodymium as dopant. Nd-doping leads to a shift of the maximum nucleation rate towards reduced temperatures and a decrease in the rate of growth compared to undoped films. The PZT-films are prepared by a sol-gel-process in fourfold multilayers with a composition near the morphotropic phase boundary, where the tetragonal und rhombohedral perovskite-phases coexist. The crystallisation in Nd-doped and undoped films takes place heterogeneously, preferentially at the interfaces and on the surface of the multilayered films as well as on the inner surface of pores within the films. For the first time, the Zr:Ti fluctuation phenomena emerging in sol-gel derived PZT films is related to the microstructure and the local phase content on a nanometer scale. In this connection it is proved, that long-distance Zr:Ti gradients arise preferentially before and during the crystallisation of the pyrochlore phase. During the following crystallisation of the perovskite phase, the crystallites grow across these gradients without modifying them. It is pointed out that the fluctuation in the Zr:Ti ratio has only minor influence on the amount of the tetragonal or rhombohedral distortion of the crystallites after the transition from the para- to the ferroelectric state due to

Preparation of PZT thin films on YBCO electrodes by KrF excimer laser ablation technique

International Nuclear Information System (INIS)

Kurogi, H.; Yamagata, Y.; Ebihara, K.

1998-01-01

Pb(Zr X Ti 1-X )O 3 (PZT) films have excellent ferroelectric, optical, piezoelectric, and pyroelectric properties. We prepared PZT thin films by the excimer laser ablation technique. A pulsed KrF excimer laser (Lambda Physik LPX305icc, pulse duration of 25 ns, λ=248 nm, 850 mJ Max.) was used to ablate the bulk targets. We investigated the influence of bottom electrode materials on the characteristics of the PZT thin films prepared on Pt and YBCO underlayers. The X-ray diffraction (XRD) patterns showed that the PZT films prepared with a laser fluence of 2 Jcm -2 on YBCO/MgO(100) substrate at a wide temperature range of 550-680 C have a perovskite (001) structure. At the same laser fluence, the PZT films prepared on Pt/MgO(100) substrate have a perovskite (001) structure only at 650 C. The polarization-electric field (P-E) characteristics and fatigue properties of PZT thin films were measured by the Sawyer-Tower circuit. The remnant polarization and coercive field have been found to be P r =15 μC cm -2 , 30 μC cm -2 and E c =200 kV cm -1 , 100 kV cm -1 for Au/PZT/Pt/MgO and Au/PZT/YBCO/MgO correspondingly. The remnant polarization of Au/PZT/YBCO/MgO thin film was reduced to one-half after about 10 8 cycles of switching. (orig.)

A new traveling wave ultrasonic motor using thick ring stator with nested PZT excitation.

Science.gov (United States)

Chen, Weishan; Shi, Shengjun; Liu, Yingxiang; Li, Pei

2010-05-01

To avoid the disadvantages of conventional traveling wave ultrasonic motors--lower efficiency PZT working mode of d(31), fragility of the PZT element under strong excitation, fatigue of the adhesive layer under harsh environmental conditions, and low volume of the PZT material in the stator--a new type of traveling wave ultrasonic motor is presented in this paper. Here we implement the stator by nesting 64 PZT stacks in 64 slots specifically cut in a thick metal ring and 64 block springs nested within another 64 slots to produce preloading on the PZT stacks. In this new design, the d33 mode of the PZT is used to excite the flexural vibrations of the stator, and fragility of the PZT ceramics and fatigue of the adhesive layer are no longer an issue. The working principle, FEM simulation, fabrication, and performance measurements of a prototype motor were demonstrated to validate the proposed ideas. Typical output of the prototype motor is no-load speed of 15 rpm and maximum torque of 7.96 N x m. Further improvement will potentially enhance its features by increasing the accuracy in fabrication and adopting appropriate frictional material into the interface between the stator and the rotor.

Preparation of PZT thin films on YBCO electrodes by KrF excimer laser ablation technique

Energy Technology Data Exchange (ETDEWEB)

Kurogi, H; Yamagata, Y; Ebihara, K [Kumamoto Univ. (Japan). Dept. of Electr. Eng. and Comput. Sci.; Inoue, N [Kyushu Electric Power Co., Inc., Suizenji, 1-6-36, Kumamoto 862 (Japan)

1998-03-01

Pb(Zr{sub X}Ti{sub 1-X})O{sub 3} (PZT) films have excellent ferroelectric, optical, piezoelectric, and pyroelectric properties. We prepared PZT thin films by the excimer laser ablation technique. A pulsed KrF excimer laser (Lambda Physik LPX305icc, pulse duration of 25 ns, {lambda}=248 nm, 850 mJ Max.) was used to ablate the bulk targets. We investigated the influence of bottom electrode materials on the characteristics of the PZT thin films prepared on Pt and YBCO underlayers. The X-ray diffraction (XRD) patterns showed that the PZT films prepared with a laser fluence of 2 Jcm{sup -2} on YBCO/MgO(100) substrate at a wide temperature range of 550-680 C have a perovskite (001) structure. At the same laser fluence, the PZT films prepared on Pt/MgO(100) substrate have a perovskite (001) structure only at 650 C. The polarization-electric field (P-E) characteristics and fatigue properties of PZT thin films were measured by the Sawyer-Tower circuit. The remnant polarization and coercive field have been found to be P{sub r}=15 {mu}C cm{sup -2}, 30 {mu}C cm{sup -2} and E{sub c}=200 kV cm{sup -1}, 100 kV cm{sup -1} for Au/PZT/Pt/MgO and Au/PZT/YBCO/MgO correspondingly. The remnant polarization of Au/PZT/YBCO/MgO thin film was reduced to one-half after about 10{sup 8} cycles of switching. (orig.) 7 refs.

Polymer-ceramic piezoelectric composites (PZT)

International Nuclear Information System (INIS)

Bassora, L.A.; Eiras, J.A.

1992-01-01

Polymer-ceramic piezoelectric transducers, with 1-3 of connectivity were prepared with different concentration of ceramic material. Piezoelectric composites, with equal electromechanical coupling factor and acoustic impedance of one third from that ceramic transducer, were obtained when the fractionary volume of PZT reach 30%. (C.G.C.)

Optimizing Pt/TiO2 templates for textured PZT growth and MEMS devices

Science.gov (United States)

Potrepka, Daniel; Fox, Glenn; Sanchez, Luz; Polcawich, Ronald

2013-03-01

Crystallographic texture of lead zirconate titanate (PZT) thin films strongly influences piezoelectric properties used in MEMS applications. Textured growth can be achieved by relying on crystal growth habit and can also be initiated by the use of a seed-layer heteroepitaxial template. Template choice and the process used to form it determine structural quality, ultimately influencing performance and reliability of MEMS PZT devices such as switches, filters, and actuators. This study focuses on how 111-textured PZT is generated by a combination of crystal habit and templating mechanisms that occur in the PZT/bottom-electrode stack. The sequence begins with 0001-textured Ti deposited on thermally grown SiO2 on a Si wafer. The Ti is converted to 100-textured TiO2 (rutile) through thermal oxidation. Then 111-textured Pt can be grown to act as a template for 111-textured PZT. Ti and Pt are deposited by DC magnetron sputtering. TiO2 and Pt film textures and structure were optimized by variation of sputtering deposition times, temperatures and power levels, and post-deposition anneal conditions. The relationship between Ti, TiO2, and Pt texture and their impact on PZT growth will be presented. Also affiliated with U.S. Army Research Lab, Adelphi, MD 20783, USA

Phase and Texture Evolution in Chemically Derived PZT Thin Films on Pt Substrates

Science.gov (United States)

2014-09-01

function of heating rate. The FWHM of the Ill PZT texture components is sim 2978 Journal of the American Ceramic Society Mhin et al. Vol. 97, No. 9...Z39.18 ABSTRACT Phase and Texture Evolution in Chemically Derived PZT Thin Films on Pt Substrates Report Title The crystallization of lead zirconate...phase influencing texture evolution. The results suggest that PZT nucleates directly on Pt, which explains the observation of a more highly oriented

Piezoelectric response of a PZT thin film to magnetic fields from permanent magnet and coil combination

Energy Technology Data Exchange (ETDEWEB)

Guiffard, B.; Seveno, R. [Universite de Nantes, Lunam Universite, IETR UMR CNRS 6164, Nantes (France)

2014-07-10

In this study, we report the magnetically induced electric field E{sub 3} in Pb(Zr{sub 0.57}Ti{sub 0.43})O{sub 3} (PZT) thin films, when they are subjected to both dynamic magnetic induction (magnitude B{sub ac} at 45 kHz) and static magnetic induction (B{sub dc}) generated by a coil and a single permanent magnet, respectively. It is found that highest sensitivity to B{sub dc} - Δ vertical stroke E{sub 3} vertical stroke ΔB{sub dc} - is achieved for the thin film with largest effective electrode. This magnetoelectric (ME) effect is interpreted in terms of coupling between eddy current-induced Lorentz forces (stress) in the electrodes of PZT and piezoelectricity. Such coupling was evidenced by convenient modelling of experimental variations of electric field magnitude with both B{sub ac} and B{sub dc} induction magnitudes, providing imperfect open circuit condition was considered. Phase angle of E{sub 3} versus B{sub dc} could also be modelled. At last, the results show that similar to multilayered piezoelectric-magnetostrictive composite film, a PZT thin film made with a simple manufacturing process can behave as a static or dynamic magnetic field sensor. In this latter case, a large ME voltage coefficient of α = vertical stroke E{sub 3} vertical stroke /B{sub ac} = 3.55 V/cm Oe under B{sub dc} = 0.3 T was found. All these results may provide promising low-cost magnetic energy harvesting applications with microsized systems. (orig.)

Pressure-induced ferroelectric to antiferroelectric phase transformation in porous PZT95/5 ceramics

International Nuclear Information System (INIS)

Zeng, T.; Dong, X.L.; Chen, X.F.; Yao, C.H.; He, H.L.

2007-01-01

The hydrostatic pressure-induced ferroelectric to antiferroelectric (FE-AFE) phase transformation of PZT95/5 ceramics was investigated as a function of porosity, pore shape and pore size. FE-AFE phase transformations were more diffuse and occurred at lower hydrostatic pressures with increasing porosity. The porous PZT95/5 ceramics with spherical pores exhibited higher transformation pressures than those with irregular pores. Moreover, FE-AFE phase transformations of porous PZT95/5 ceramics with polydisperse irregular pores were more diffuse than those of porous PZT95/5 ceramics with monodisperse irregular pores. The relation between pore structure and hydrostatic pressure-induced FE-AFE transformation was established according to stress concentration theory. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Improving yield of PZT piezoelectric devices on glass substrates

Science.gov (United States)

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

2012-10-01

The proposed SMART-X telescope includes adaptive optics systems that use piezoelectric lead zirconate titanate (PZT) films deposited on flexible glass substrates. Several processing constraints are imposed by current designs: the crystallization temperature must be kept below 550 °C, the total stress in the film must be minimized, and the yield on 1 cm2 actuator elements should be work, RF magnetron sputtering was used to deposit films since chemical solution deposition (CSD) led to warping of large area flexible glass substrates. A PZT 52/48 film that wasdeposited at 4 mTorr and annealed at 550 °C for 24 hours showed no detectable levels of either PbO or pyrochlore second phases. Large area electrodes (1cm x 1 cm) were deposited on 4" glass substrates. Initially, the yield of the devices was low, however, two methods were employed to increase the yield to near 100 %. The first method included a more rigorous cleaning to improve the continuity of the Pt bottom electrode. The second method was to apply 3 V DC across the capacitor structure to burn out regions of defective PZT. The result of this latter method essentially removed conducting filaments in the PZT but left the bulk of the material undamaged. By combining these two methods, the yield on the large area electrodes improved from < 10% to nearly 100%.

Study on oxidization of Ru and its application as electrode of PZT capacitor for FeRAM

International Nuclear Information System (INIS)

Jia Ze; Ren Tianling; Liu Tianzhi; Hu Hong; Zhang Zhigang; Xie Dan; Liu Litian

2007-01-01

Oxidization for Ru through anneal with plenteous oxygen atmosphere and its application as the top electrode of sol-gel PZT capacitor are investigated in this study. PZT capacitor with RuO 2 or oxygen-doped Ru as top electrode can be obtained from Ru/PZT/Pt capacitor through slow-rate anneal at 650 deg. C for 20 min in cannulation furnace. It has larger remanent polarization, better rectangle shape, better fatigue properties and lower leakage current than the other capacitors with PZT film prepared by the same process and different top electrodes in this study. Plenteous oxygen atmosphere and 650 deg. C in cannulation furnace are important conditions for the oxidation of Ru and renewed crystallization of PZT in this capacitor. Plenteous oxygen at interface can compensate the oxygen vacancies at PZT/electrode interface, which results in the above good characteristics

Enhanced pyroelectric and piezoelectric properties of PZT with aligned porosity for energy harvesting applications† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7ta00967d Click here for additional data file.

Science.gov (United States)

Zhang, Yan; Xie, Mengying; Roscow, James; Bao, Yinxiang; Zhou, Kechao

2017-01-01

This paper demonstrates the significant benefits of exploiting highly aligned porosity in piezoelectric and pyroelectric materials for improved energy harvesting performance. Porous lead zirconate (PZT) ceramics with aligned pore channels and varying fractions of porosity were manufactured in a water-based suspension using freeze-casting. The aligned porous PZT ceramics were characterized in detail for both piezoelectric and pyroelectric properties and their energy harvesting performance figures of merit were assessed parallel and perpendicular to the freezing direction. As a result of the introduction of porosity into the ceramic microstructure, high piezoelectric and pyroelectric harvesting figures of merits were achieved for porous freeze-cast PZT compared to dense PZT due to the reduced permittivity and volume specific heat capacity. Experimental results were compared to parallel and series analytical models with good agreement and the PZT with porosity aligned parallel to the freezing direction exhibited the highest piezoelectric and pyroelectric harvesting response; this was a result of the enhanced interconnectivity of the ferroelectric material along the poling direction and reduced fraction of unpoled material that leads to a higher polarization. A complete thermal energy harvesting system, composed of a parallel-aligned PZT harvester element and an AC/DC converter, was successfully demonstrated by charging a storage capacitor. The maximum energy density generated by the 60 vol% porous parallel-connected PZT when subjected to thermal oscillations was 1653 μJ cm–3, which was 374% higher than that of the dense PZT with an energy density of 446 μJ cm–3. The results are beneficial for the design and manufacture of high performance porous pyroelectric and piezoelectric materials in devices for energy harvesting and sensor applications. PMID:28580142

Development of PZT Actuated Valveless Micropump

Directory of Open Access Journals (Sweden)

Fathima Rehana Munas

2018-04-01

Full Text Available A piezoelectrically actuated valveless micropump has been designed and developed. The principle components of this system are piezoelectrically actuated (PZT metal diaphragms and a complete fluid flow system. The design of this pump mainly focuses on a cross junction, which is generated by a nozzle jet attached to a pump chamber and the intersection of two inlet channels and an outlet channel respectively. During each PZT diaphragm vibration cycle, the junction connecting the inlet and outlet channels with the nozzle jet permits consistencies in fluidic momentum and resistances in order to facilitate complete fluidic path throughout the system, in the absence of any physical valves. The entire micropump structure is fabricated as a plate-by-plate element of polymethyl methacrylate (PMMA sheets and sandwiched to get required fluidic network as well as the overall device. In order to identify the flow characteristics, and to validate the test results with numerical simulation data, FEM analysis using ANSYS was carried out and an eigenfrequency analysis was performed to the PZT diaphragm using COMSOL Multiphysics. In addition, the control system of the pump was designed and developed to change the applied frequency to the piezoelectric diaphragms. The experimental data revealed that the maximum flow rate is 31.15 mL/min at a frequency of 100 Hz. Our proposed design is not only for a specific application but also useful in a wide range of biomedical applications.

Development of PZT Actuated Valveless Micropump.

Science.gov (United States)

Munas, Fathima Rehana; Melroy, Gehan; Abeynayake, Chamitha Bhagya; Chathuranga, Hiniduma Liyanage; Amarasinghe, Ranjith; Kumarage, Pubudu; Dau, Van Thanh; Dao, Dzung Viet

2018-04-24

A piezoelectrically actuated valveless micropump has been designed and developed. The principle components of this system are piezoelectrically actuated (PZT) metal diaphragms and a complete fluid flow system. The design of this pump mainly focuses on a cross junction, which is generated by a nozzle jet attached to a pump chamber and the intersection of two inlet channels and an outlet channel respectively. During each PZT diaphragm vibration cycle, the junction connecting the inlet and outlet channels with the nozzle jet permits consistencies in fluidic momentum and resistances in order to facilitate complete fluidic path throughout the system, in the absence of any physical valves. The entire micropump structure is fabricated as a plate-by-plate element of polymethyl methacrylate (PMMA) sheets and sandwiched to get required fluidic network as well as the overall device. In order to identify the flow characteristics, and to validate the test results with numerical simulation data, FEM analysis using ANSYS was carried out and an eigenfrequency analysis was performed to the PZT diaphragm using COMSOL Multiphysics. In addition, the control system of the pump was designed and developed to change the applied frequency to the piezoelectric diaphragms. The experimental data revealed that the maximum flow rate is 31.15 mL/min at a frequency of 100 Hz. Our proposed design is not only for a specific application but also useful in a wide range of biomedical applications.

A flexible ultrasound transducer array with micro-machined bulk PZT.

Science.gov (United States)

Wang, Zhe; Xue, Qing-Tang; Chen, Yuan-Quan; Shu, Yi; Tian, He; Yang, Yi; Xie, Dan; Luo, Jian-Wen; Ren, Tian-Ling

2015-01-23

This paper proposes a novel flexible piezoelectric micro-machined ultrasound transducer, which is based on PZT and a polyimide substrate. The transducer is made on the polyimide substrate and packaged with medical polydimethylsiloxane. Instead of etching the PZT ceramic, this paper proposes a method of putting diced PZT blocks into holes on the polyimide which are pre-etched. The device works in d31 mode and the electromechanical coupling factor is 22.25%. Its flexibility, good conformal contacting with skin surfaces and proper resonant frequency make the device suitable for heart imaging. The flexible packaging ultrasound transducer also has a good waterproof performance after hundreds of ultrasonic electric tests in water. It is a promising ultrasound transducer and will be an effective supplementary ultrasound imaging method in the practical applications.

A Flexible Ultrasound Transducer Array with Micro-Machined Bulk PZT

Directory of Open Access Journals (Sweden)

Zhe Wang

2015-01-01

Full Text Available This paper proposes a novel flexible piezoelectric micro-machined ultrasound transducer, which is based on PZT and a polyimide substrate. The transducer is made on the polyimide substrate and packaged with medical polydimethylsiloxane. Instead of etching the PZT ceramic, this paper proposes a method of putting diced PZT blocks into holes on the polyimide which are pre-etched. The device works in d31 mode and the electromechanical coupling factor is 22.25%. Its flexibility, good conformal contacting with skin surfaces and proper resonant frequency make the device suitable for heart imaging. The flexible packaging ultrasound transducer also has a good waterproof performance after hundreds of ultrasonic electric tests in water. It is a promising ultrasound transducer and will be an effective supplementary ultrasound imaging method in the practical applications.

A Reusable PZT Transducer for Monitoring Initial Hydration and Structural Health of Concrete

Directory of Open Access Journals (Sweden)

Yaowen Yang

2010-05-01

Full Text Available During the construction of a concrete structure, strength monitoring is important to ensure the safety of both personnel and the structure. Furthermore, to increase the efficiency of in situ casting or precast of concrete, determining the optimal time of demolding is important for concrete suppliers. Surface bonded lead zirconate titanate (PZT transducers have been used for damage detection and parameter identification for various engineering structures over the last two decades. In this work, a reusable PZT transducer setup for monitoring initial hydration of concrete and structural health is developed, where a piece of PZT is bonded to an enclosure with two bolts tightened inside the holes drilled in the enclosure. An impedance analyzer is used to acquire the admittance signatures of the PZT. Root mean square deviation (RMSD is employed to associate the change in concrete strength with changes in the PZT admittance signatures. The results show that the reusable setup is able to effectively monitor the initial hydration of concrete and the structural health. It can also be detached from the concrete for future re-use.

A Reusable PZT Transducer for Monitoring Initial Hydration and Structural Health of Concrete

Science.gov (United States)

Yang, Yaowen; Divsholi, Bahador Sabet; Soh, Chee Kiong

2010-01-01

During the construction of a concrete structure, strength monitoring is important to ensure the safety of both personnel and the structure. Furthermore, to increase the efficiency of in situ casting or precast of concrete, determining the optimal time of demolding is important for concrete suppliers. Surface bonded lead zirconate titanate (PZT) transducers have been used for damage detection and parameter identification for various engineering structures over the last two decades. In this work, a reusable PZT transducer setup for monitoring initial hydration of concrete and structural health is developed, where a piece of PZT is bonded to an enclosure with two bolts tightened inside the holes drilled in the enclosure. An impedance analyzer is used to acquire the admittance signatures of the PZT. Root mean square deviation (RMSD) is employed to associate the change in concrete strength with changes in the PZT admittance signatures. The results show that the reusable setup is able to effectively monitor the initial hydration of concrete and the structural health. It can also be detached from the concrete for future re-use. PMID:22399929

A reusable PZT transducer for monitoring initial hydration and structural health of concrete.

Science.gov (United States)

Yang, Yaowen; Divsholi, Bahador Sabet; Soh, Chee Kiong

2010-01-01

During the construction of a concrete structure, strength monitoring is important to ensure the safety of both personnel and the structure. Furthermore, to increase the efficiency of in situ casting or precast of concrete, determining the optimal time of demolding is important for concrete suppliers. Surface bonded lead zirconate titanate (PZT) transducers have been used for damage detection and parameter identification for various engineering structures over the last two decades. In this work, a reusable PZT transducer setup for monitoring initial hydration of concrete and structural health is developed, where a piece of PZT is bonded to an enclosure with two bolts tightened inside the holes drilled in the enclosure. An impedance analyzer is used to acquire the admittance signatures of the PZT. Root mean square deviation (RMSD) is employed to associate the change in concrete strength with changes in the PZT admittance signatures. The results show that the reusable setup is able to effectively monitor the initial hydration of concrete and the structural health. It can also be detached from the concrete for future re-use.

Thin PZT-Based Ferroelectric Capacitors on Flexible Silicon for Nonvolatile Memory Applications

KAUST Repository

Ghoneim, Mohamed T.; Zidan, Mohammed A.; Al-Nassar, Mohammed Y.; Hanna, Amir; Kosel, Jü rgen; Salama, Khaled N.; Hussain, Muhammad Mustafa

2015-01-01

A flexible version of traditional thin lead zirconium titanate ((Pb1.1Zr0.48Ti0.52O3)-(PZT)) based ferroelectric random access memory (FeRAM) on silicon shows record performance in flexible arena. The thin PZT layer requires lower operational

The nature of the photoluminescence in amorphized PZT

International Nuclear Information System (INIS)

Silva, M.S.; Cilense, M.; Orhan, E.; Goes, M.S.; Machado, M.A.C.; Santos, L.P.S.; Paiva-Santos, C.O.; Longo, E.; Varela, J.A.; Zaghete, M.A.; Pizani, P.S.

2005-01-01

The polymeric precursor method was used to synthesize lead zirconate titanate powder (PZT). The crystalline powder was then amorphized by a high-energy ball milling process during 120 h. A strong photoluminescence emission was observed at room temperature for the amorphized PZT powder. The powders were characterized by XRD and the percentage of amorphous phase was calculated through Rietveld refinement. The microstructure for both phases was investigated by TEM. The optical gap was calculated through the Wood and Tauc method using the UV-Vis. data. Quantum mechanical calculations were carried out to give an interpretation of the photoluminescence in terms of electronic structure

Quantitative comparison of PZT and CMUT probes for photoacoustic imaging: Experimental validation.

Science.gov (United States)

Vallet, Maëva; Varray, François; Boutet, Jérôme; Dinten, Jean-Marc; Caliano, Giosuè; Savoia, Alessandro Stuart; Vray, Didier

2017-12-01

Photoacoustic (PA) signals are short ultrasound (US) pulses typically characterized by a single-cycle shape, often referred to as N-shape. The spectral content of such wideband signals ranges from a few hundred kilohertz to several tens of megahertz. Typical reception frequency responses of classical piezoelectric US imaging transducers, based on PZT technology, are not sufficiently broadband to fully preserve the entire information contained in PA signals, which are then filtered, thus limiting PA imaging performance. Capacitive micromachined ultrasonic transducers (CMUT) are rapidly emerging as a valid alternative to conventional PZT transducers in several medical ultrasound imaging applications. As compared to PZT transducers, CMUTs exhibit both higher sensitivity and significantly broader frequency response in reception, making their use attractive in PA imaging applications. This paper explores the advantages of the CMUT larger bandwidth in PA imaging by carrying out an experimental comparative study using various CMUT and PZT probes from different research laboratories and manufacturers. PA acquisitions are performed on a suture wire and on several home-made bimodal phantoms with both PZT and CMUT probes. Three criteria, based on the evaluation of pure receive impulse response, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) respectively, have been used for a quantitative comparison of imaging results. The measured fractional bandwidths of the CMUT arrays are larger compared to PZT probes. Moreover, both SNR and CNR are enhanced by at least 6 dB with CMUT technology. This work highlights the potential of CMUT technology for PA imaging through qualitative and quantitative parameters.

Strong nonlinear harmonic generation in a PZT/Aluminum resonator

Energy Technology Data Exchange (ETDEWEB)

Parenthoine, D; Haumesser, L; Meulen, F Vander; Tran-Huu-Hue, L-P, E-mail: parenthoine@univ-tours.f [University Francois Rabelais of Tours, U 930 Imagerie et Cerveau, CNRS 2448, ENIVL, rue de la Chocolaterie, BP 3410, 41034 Blois (France)

2009-11-01

In this work, the extentional vibration mode of a coupled PZT/ Aluminum rod resonator is studied experimentally. Geometrical characteristics of the PZT are its 27 mm length and its 4x4 mm{sup 2} cross section area. The excitation voltage consists in sinusoidal bursts in the frequency range (20-80 kHz). Velocity measurements are performed at both ends of this system, using a laser probe. Strong harmonic distortions in the mechanical response (up to -20 dB with respect to the primary wave amplitude) have been observed. The corresponding input levels are far lower than those which are necessary to observe quadratic second harmonic generation in a free PZT resonator. The strong nonlinear effect can be explained as a super-harmonic resonance of the system due to a specific ratio between the eigen frequencies of the two parts of the resonator. Evolution of fundamental and harmonic responses are observed as a function of input levels, highlighting hysteretic behavior.

Enhancement of fatigue endurance in ferroelectric PZT ceramic by the addition of bismuth layered SBT

Science.gov (United States)

Namsar, O.; Pojprapai, S.; Watcharapasorn, A.; Jiansirisomboon, S.

2014-10-01

Electrical fatigue properties of (1-x)PZT-xSBT ceramics (x = 0-1.0 weight fraction) were characterized. It was found that pure PZT ceramic had severe polarization fatigue. This was mainly attributed to an occurrence of the macroscopic cracks at near-electrode regions. On the contrary, pure SBT ceramic exhibited excellent fatigue resistance, which was attributed primarily to weak domain wall pinning. As small amount of SBT (0.1 ≤ x ≤ 0.3) was added into PZT, a small reduction of remanent polarization after fatigue process was observed. This demonstrated that these ceramics had high stability during the repeated domain switching due to their low oxygen vacancy concentration. Therefore, these results suggested that this new ceramic PZT-SBT system seemed to be an alternative material for replacing pure PZT in ferroelectric memory applications.

Development of PZT-excited stroboscopic shearography for full-field nondestructive evaluation.

Science.gov (United States)

Asemani, Hamidreza; Park, Jinwoo; Lee, Jung-Ryul; Soltani, Nasser

2017-05-01

Nondestructive evaluation using shearography requires a way to stress the inspection target. This technique is able to directly measure the displacement gradient distribution on the object surface. Shearography visualizes the internal structural damages as the anomalous pattern in the shearograpic fringe pattern. A piezoelectric (PZT) excitation system is able to generate loadings in the vibrational, acoustic, and ultrasonic regimes. In this paper, we propose a PZT-excited stroboscopic shearography. The PZT excitation could generate vibrational loading, a stationary wavefield, and a nonstationary propagation wave to fulfill the external loading requirement of shearography. The sweeping of the PZT excitation frequency, the formation of a standing wave, and a small shearing to suppress the incident wave were powerful controllable tools to detect the defects. The sweeping of the PZT excitation frequency enabled us to determine one of the defect-sensitive frequencies almost in real time. In addition, because the defect sensitive frequencies always existed in wide and plural ranges, the risk of the defect being overlooked by the inspector could be alleviated. The results of evaluation using stroboscopic shearography showed that an artificial 20 mm-diameter defect could be visualized at the excitation frequencies of 5-8 kHz range and 12.5-15.5 kHz range. This technique provided full field reliable and repeatable inspection results. Additionally, the proposed method overcame the important drawback of the time-averaged shearography, being required to identify the resonance vibration frequency sensitive to the defect.

The development of a PZT-based microdrive for neural signal recording

International Nuclear Information System (INIS)

Park, Sangkyu; Yoon, Euisung; Park, Sukho; Lee, Sukchan; Shin, Hee-sup; Park, Hyunjun; Kim, Byungkyu; Kim, Daesoo; Park, Jongoh

2008-01-01

A hand-controlled microdrive has been used to obtain neural signals from rodents such as rats and mice. However, it places severe physical stress on the rodents during its manipulation, and this stress leads to alertness in the mice and low efficiency in obtaining neural signals from the mice. To overcome this issue, we developed a novel microdrive, which allows one to adjust the electrodes by a piezoelectric device (PZT) with high precision. Its mass is light enough to install on the mouse's head. The proposed microdrive has three H-type PZT actuators and their guiding structure. The operation principle of the microdrive is based on the well known inchworm mechanism. When the three PZT actuators are synchronized, linear motion of the electrode is produced along the guiding structure. The electrodes used for the recording of the neural signals from neuron cells were fixed at one of the PZT actuators. Our proposed microdrive has an accuracy of about 400 nm and a long stroke of about 5 mm. In response to formalin-induced pain, single unit activities are robustly measured at the thalamus with electrodes whose vertical depth is adjusted by the microdrive under urethane anesthesia. In addition, the microdrive was efficient in detecting neural signals from mice that were moving freely. Thus, the present study suggests that the PZT-based microdrive could be an alternative for the efficient detection of neural signals from mice during behavioral states without any stress to the mice. (technical note)

An Unconventional Inchworm Actuator Based on PZT/ERFs Control Technology.

Science.gov (United States)

Liu, Guojun; Zhang, Yanyan; Liu, Jianfang; Li, Jianqiao; Tang, Chunxiu; Wang, Tengfei; Yang, Xuhao

2016-01-01

An unconventional inchworm actuator for precision positioning based on piezoelectric (PZT) actuation and electrorheological fluids (ERFs) control technology is presented. The actuator consists of actuation unit (PZT stack pump), fluid control unit (ERFs valve), and execution unit (hydraulic actuator). In view of smaller deformation of PZT stack, a new structure is designed for actuation unit, which integrates the advantages of two modes (namely, diaphragm type and piston type) of the volume changing of pump chamber. In order to improve the static shear yield strength of ERFs, a composite ERFs valve is designed, which adopts the series-parallel plate compound structure. The prototype of the inchworm actuator has been designed and manufactured in the lab. Systematic test results indicate that the displacement resolution of the unconventional inchworm actuator reaches 0.038 μm, and the maximum driving force and velocity are 42 N, 14.8 mm/s, respectively. The optimal working frequency for the maximum driving velocity is 120 Hz. The complete research and development processes further confirm the feasibility of developing a new type of inchworm actuator with high performance based on PZT actuation and ERFs control technology, which provides a reference for the future development of a new type of actuator.

An Unconventional Inchworm Actuator Based on PZT/ERFs Control Technology

Directory of Open Access Journals (Sweden)

Guojun Liu

2016-01-01

Full Text Available An unconventional inchworm actuator for precision positioning based on piezoelectric (PZT actuation and electrorheological fluids (ERFs control technology is presented. The actuator consists of actuation unit (PZT stack pump, fluid control unit (ERFs valve, and execution unit (hydraulic actuator. In view of smaller deformation of PZT stack, a new structure is designed for actuation unit, which integrates the advantages of two modes (namely, diaphragm type and piston type of the volume changing of pump chamber. In order to improve the static shear yield strength of ERFs, a composite ERFs valve is designed, which adopts the series-parallel plate compound structure. The prototype of the inchworm actuator has been designed and manufactured in the lab. Systematic test results indicate that the displacement resolution of the unconventional inchworm actuator reaches 0.038 μm, and the maximum driving force and velocity are 42 N, 14.8 mm/s, respectively. The optimal working frequency for the maximum driving velocity is 120 Hz. The complete research and development processes further confirm the feasibility of developing a new type of inchworm actuator with high performance based on PZT actuation and ERFs control technology, which provides a reference for the future development of a new type of actuator.

Mechanical and electrical strain response of a piezoelectric auxetic PZT lattice structure

Science.gov (United States)

Fey, Tobias; Eichhorn, Franziska; Han, Guifang; Ebert, Kathrin; Wegener, Moritz; Roosen, Andreas; Kakimoto, Ken-ichi; Greil, Peter

2016-01-01

A two-dimensional auxetic lattice structure was fabricated from a PZT piezoceramic. Tape casted and sintered sheets with a thickness of 530 μm were laser cut into inverted honeycomb lattice structure with re-entrant cell geometry (θ = -25°) and poling direction oriented perpendicular to the lattice plane. The in-plane strain response upon applying an uniaxial compression load as well as an electric field perpendicular to the lattice plane were analyzed by a 2D image data detection analysis. The auxetic lattice structure exhibits orthotropic deformation behavior with a negative in-plane Poisson’s ratio of -2.05. Compared to PZT bulk material the piezoelectric auxetic lattice revealed a strain amplification by a factor of 30-70. Effective transversal coupling coefficients {{d}al}31 of the PZT lattice exceeding 4 × 103 pm V-1 were determined which result in an effective hydrostatic coefficient {{d}al}h 66 times larger than that of bulk PZT.

Dielectric response of capacitor structures based on PZT annealed at different temperatures

Energy Technology Data Exchange (ETDEWEB)

Kamenshchikov, Mikhail V., E-mail: Mikhailkamenshchikov@yandex.ru [Tver State University, 170002, Tver (Russian Federation); Solnyshkin, Alexander V. [Tver State University, 170002, Tver (Russian Federation); Pronin, Igor P. [Ioffe Institute, 194021, St. Petersburg (Russian Federation)

2016-12-09

Highlights: • Correlation of the microstructure of PZT films and dielectric response was found. • Difference of dielectric responses under low and high bias is caused by domains. • Internal fields is discussed on the basis of the space charges. • Dependences of PZT films characteristics on synthesis temperature are extremal. - Abstract: Dielectric response of thin-film capacitor structures of Pt/PZT/Pt deposited by the RF magnetron sputtering method and annealed at temperatures of 540–570 °C was investigated. It was found that dielectric properties of these structures depend on the synthesis temperature. Stability of a polarized state is considered on the basis of the analysis of hysteresis loops and capacitance–voltage (C–V) characteristics. The contribution of the domain mechanism in the dielectric response of the capacitor structure comprising a ferroelectric is discussed. Extreme dependences of electrophysical characteristics of PZT films on their synthesis temperature were observed. Correlation of dielectric properties with microstructure of these films is found out.

Model-Based, Closed-Loop Control of PZT Creep for Cavity Ring-Down Spectroscopy.

Science.gov (United States)

McCartt, A D; Ognibene, T J; Bench, G; Turteltaub, K W

2014-09-01

Cavity ring-down spectrometers typically employ a PZT stack to modulate the cavity transmission spectrum. While PZTs ease instrument complexity and aid measurement sensitivity, PZT hysteresis hinders the implementation of cavity-length-stabilized, data-acquisition routines. Once the cavity length is stabilized, the cavity's free spectral range imparts extreme linearity and precision to the measured spectrum's wavelength axis. Methods such as frequency-stabilized cavity ring-down spectroscopy have successfully mitigated PZT hysteresis, but their complexity limits commercial applications. Described herein is a single-laser, model-based, closed-loop method for cavity length control.

Pyroelectric Ceramics as Temperature Sensors for Energy System Applications

Science.gov (United States)

Silva, Jorge Luis

respectively when compared with thermocouple measurements. The second phase of this study focused on developing a wireless temperature sensor with lead zirconate titanate (PZT) as the pyroelectric material. This wireless temperature sensor consists of generating current by the PZT when exposed to a rate of temperature change with time, which was conducted to a built electromagnet to produce a magnetic field. The magnetic field was captured wirelessly with a milligaussmeter at a certain distance. Pyroelectric property of PZT (-40x10-5 C/m2 °C at 25 °C) is higher than that of the lithium niobate (-8.5x10-5 C/m2 °C at 25 °C), which was necessary to be able to generate the necessary pyroelectric current to make magnetic field detectable by the milligaussmeter. The electromagnet body was 3D printed with ABS material and surrounded with winding wire material. Before attempting a wireless temperature measurement, several attempts to measure the magnetic field at different distances away from the electromagnet were done. At the applied heating rates, the milligaussmeter was able to measure magnetic field up to 1.27 cm away from the electromagnet edge. A PZT sensor with a thickness of 0.1 cm was tested for use in the wireless temperature measurement configuration. For more accurate wireless temperature measurements, a similar pyroelectric coefficient measurement technique as used in phase one was done. The pyroelectric coefficient was found to increase from -40x10 -5 C/m2 °C to -71.84x10-5 C/m 2 °C from 25 °C to 122 °C, respectively. The PZT sensor was then tested for wireless temperature measurement at a distance of 1.27 cm at set temperatures of 100 °C, 150 °C, and 200 °C, and showed a maximum 10.47 % deviation when compared to thermocouple reading. In order to increase the distance that the wireless temperature sensor can read, a ferromagnetic material was placed inside the electromagnet. The sensor was tested for wireless temperature measurement at 1.27 cm, 2.54 cm and 3

Pyroelectric Charge Release in Rhombohedral PZT

NARCIS (Netherlands)

Noheda, Beatriz; Duan, Ning; Cereceda, Noé; Gonzalo, Julio A.

1998-01-01

A new experimental set-up controlled by computer has been made to measure the pyroelectric charge of ferroelectric materials with a relatively high conductivity at slow rates of temperature variation. It allowed us to obtain the polarisation vs. temperature behaviour of PZT with various compositions

Optimization of the low-temperature MOCVD process for PZT thin films

CERN Document Server

Wang, C H; Choi, D J

2000-01-01

Pb(Zr sub X Ti sub 1 sub - sub X)O sub 3 (PZT) thin films of about 0.34 nm were successfully grown at a low temperature of 500 .deg. C by metalorganic chemical vapor deposition with a beta-diketonate complex of Pb(tmhd) sub 2 , zirconium t-butoxide, and titanium isopropoxide as source precursors. Ferroelectric capacitors of a Pt/PZT/Pt configuration were fabricated, and their structural and electrical properties were investigated as a function of the input Pb/(Zr+Ti) and Zr/(Zr+Ti) source ratios. The structure of the as-grown films at 500 .deg. C changed from tetragonal to pseudocubic with increasing the Zr/(Zr+Ti) ratio above an input Pb/(Zr+Ti) source ratio of 5.0 while a 2nd phase of ZrO sub 2 was only observed below Pb/(Zr+Ti) ratio of 5.0, regardless of the Zr/(Zr+Ti) ratio. The dielectric constant and loss of the PZT films were 150-1200 and 0.01-0.04 at 100 kHz, respectively, Leakage current densities decreased with increasing the Zr/(Zr+Ti) ratio. The process window for growing a single phase PZT is ve...

In situ X-ray diffraction studies on the piezoelectric response of PZT thin films

Energy Technology Data Exchange (ETDEWEB)

Davydok, A., E-mail: davydok@mpie.de [Aix Marseille Université, CNRS, Université de Toulon, IM2NP UMR 7334, 13397 Marseille (France); Max-Planck-Institut für Eisenforschung, Department Structure and Nano-/Micromechanics of Materials, D-40237 Düsseldorf (Germany); Cornelius, T.W. [Aix Marseille Université, CNRS, Université de Toulon, IM2NP UMR 7334, 13397 Marseille (France); Mocuta, C. [SOLEIL Synchrotron, DiffAbs beamline, L' Orme des Merisiers, Saint-Aubin - BP 48, 91192 Gif-sur-Yvette Cedex (France); Lima, E.C. [Universidade Federal do Tocantins, 77500-000 Porto Nacional, TO (Brazil); Araujo, E.B. [Departamento de Fisica e Quimica, Universidade Estadual Paulista, Av. Brasil, 56 Centro, 15385-000 Ilha Solteira, SP (Brazil); Thomas, O. [Aix Marseille Université, CNRS, Université de Toulon, IM2NP UMR 7334, 13397 Marseille (France)

2016-03-31

Piezoelectric properties of randomly oriented self-polarized PbZr{sub 0.50}Ti{sub 0.50}O{sub 3} (PZT) thin films were investigated using in situ synchrotron X-ray diffraction. Possibilities for investigating the piezoelectric effect using micro-sized hard X-ray beams are demonstrated and perspectives for future dynamical measurements on PZT samples with variety of compositions and thicknesses are given. Studies performed on the crystalline [100, 110] directions evidenced piezoelectric anisotropy. The piezoelectric coefficient d{sub 33} was calculated in terms of the lab reference frame (d{sub perp}) and found to be two times larger along the [100] direction than along the [110] direction. The absolute values for the d{sub perp} amount to 120 and 230 pm/V being in good agreement with experimental and theoretical values found in literature for bulk PZT ceramics. - Highlights: • We performed in situ synchrotron X-ray diffraction studies on (PZT) thin films. • We discuss anisotropy of piezo effect in different crystallographic directions. • Perpendicular component Piezo coefficient of thin PZT layer is defined.

Ferroelectric properties of PZT/BFO multilayer thin films prepared using the sol-gel method.

Science.gov (United States)

Jo, Seo-Hyeon; Lee, Sung-Gap; Lee, Young-Hie

2012-01-05

In this study, Pb(Zr0.52Ti0.48)O3/BiFeO3 [PZT/BFO] multilayer thin films were fabricated using the spin-coating method on a Pt(200 nm)/Ti(10 nm)/SiO2(100 nm)/p-Si(100) substrate alternately using BFO and PZT metal alkoxide solutions. The coating-and-heating procedure was repeated several times to form the multilayer thin films. All PZT/BFO multilayer thin films show a void-free, uniform grain structure without the presence of rosette structures. The relative dielectric constant and dielectric loss of the six-coated PZT/BFO [PZT/BFO-6] thin film were approximately 405 and 0.03%, respectively. As the number of coatings increased, the remanent polarization and coercive field increased. The values for the BFO-6 multilayer thin film were 41.3 C/cm2 and 15.1 MV/cm, respectively. The leakage current density of the BFO-6 multilayer thin film at 5 V was 2.52 × 10-7 A/cm2.

Photoluminescence properties of PZT 52/48 synthesized by microwave hydrothermal method using PVA with template

Energy Technology Data Exchange (ETDEWEB)

Teixeira, G.F., E-mail: guilmina@hotmail.com [Instituto de Quimica, Universidade Estadual Paulista, Departamento de Bioquimica e Tecnologia Quimica, Rua Francisco Degni s/n, Quitandinha, 14800-900 Araraquara, SP (Brazil); Gasparotto, G. [Instituto de Quimica, Universidade Estadual Paulista, Departamento de Bioquimica e Tecnologia Quimica, Rua Francisco Degni s/n, Quitandinha, 14800-900 Araraquara, SP (Brazil); Paris, E.C. [Empresa Brasileira de Pesquisa Agropecuaria, Embrapa Instrumentacao, Rua XV de novembro, 1452, Centro, 13.569-970 Sao Carlos, SP (Brazil); Zaghete, M.A.; Longo, E.; Varela, J.A. [Instituto de Quimica, Universidade Estadual Paulista, Departamento de Bioquimica e Tecnologia Quimica, Rua Francisco Degni s/n, Quitandinha, 14800-900 Araraquara, SP (Brazil)

2012-01-15

Lead Titanate Zirconate (PZT) perovskite powders were synthesized by microwave hydrothermal method (M-H) at 180 {sup o}C for different time periods (2, 4, 8 and 12 h) with the presence of aqueous polyvinyl alcohol (PVA) solution 0.36 g L{sup -1}. The X-Ray diffraction (XRD), SE-FEG as well as the measurements of photoluminescence (PL) emission were used for monitoring the formation of a perovskite phase with random polycrystalline distortion in the structure. Emission spectra with fixed excitation wavelength of 350 nm showed higher value for the powder obtained after undergoing 8 h of treatment. A theoretical model derived from previous calculations allows us to discuss the origin of photoluminescence emission in the powders, which can be further related to the local disorder in the network of both ZrO{sub 6} and TiO{sub 6} octahedral, and dodecahedral PbO{sub 12}. The new morphology initially observed from the PZT perovskite crystal growth bearing the shape of fine plates is found to be directly related to photoluminescence emission with energy lower than that present in the PZT with cube-like morphology that emits in 560 nm. - Highlights: > This work details the efficiency of microwave hydrothermal synthesis in obtaining PZT powders. > PVA is used as a crystallization agent of PZT particles. > PZT particles presented photoluminescent (PL) behavior. > There aren't previous reports of photoluminescent PZT obtained by microwave hydrothermal synthesis. > Photoluminescence is one more interesting property for technological applications this material.

Temperature Field Analysis for PZT Pyroelectric Cells for Thermal Energy Harvesting

Directory of Open Access Journals (Sweden)

Chi-Yuan Lee

2011-11-01

Full Text Available This paper proposes the idea of etching PZT to improve the temperature variation rate of a thicker PZT sheet in order to enhance the energy conversion efficiency when used as pyroelectric cells. A partially covered electrode was proven to display a higher output response than a fully covered electrode did. A mesh top electrode monitored the temperature variation rate and the electrode area. The mesh electrode width affected the distribution of the temperature variation rate in a thinner pyroelectric material. However, a pyroelectric cell with a thicker pyroelectric material was beneficial in generating electricity pyroelectrically. The PZT sheet was further etched to produce deeper cavities and a smaller electrode width to induce lateral temperature gradients on the sidewalls of cavities under homogeneous heat irradiation, enhancing the temperature variation rate.

Temperature field analysis for PZT pyroelectric cells for thermal energy harvesting.

Science.gov (United States)

Hsiao, Chun-Ching; Ciou, Jing-Chih; Siao, An-Shen; Lee, Chi-Yuan

2011-01-01

This paper proposes the idea of etching PZT to improve the temperature variation rate of a thicker PZT sheet in order to enhance the energy conversion efficiency when used as pyroelectric cells. A partially covered electrode was proven to display a higher output response than a fully covered electrode did. A mesh top electrode monitored the temperature variation rate and the electrode area. The mesh electrode width affected the distribution of the temperature variation rate in a thinner pyroelectric material. However, a pyroelectric cell with a thicker pyroelectric material was beneficial in generating electricity pyroelectrically. The PZT sheet was further etched to produce deeper cavities and a smaller electrode width to induce lateral temperature gradients on the sidewalls of cavities under homogeneous heat irradiation, enhancing the temperature variation rate.

Note: a high-sensitivity current sensor based on piezoelectric ceramic Pb(Zr,Ti)O3 and ferromagnetic materials.

Science.gov (United States)

He, Wei; Li, Ping; Wen, Yumei; Zhang, Jitao; Yang, Aichao; Lu, Caijiang

2014-02-01

An electric current sensor using piezoelectric ceramic Pb(Zr,Ti)O3 (PZT) sandwiched between two high permeability cuboids and two NdFeB magnets is presented. The magnetic field originating from an electric wire is augmented by the high permeability cuboids. The PZT plate experiences an enhanced magnetic force and generates voltage output. When placed with a distance of d = 5.0 mm from the wire, the sensor shows a flat sensitivity of ∼5.7 mV/A in the frequency range of 30 Hz-80 Hz and an average sensitivity of 5.6 mV/A with highly linear behavior in the current range of 1 A-10 A at 50 Hz.

A PZT Actuated Triple-Finger Gripper for Multi-Target Micromanipulation

Directory of Open Access Journals (Sweden)

Tao Chen

2017-01-01

Full Text Available This paper presents a triple-finger gripper driven by a piezoceramic (PZT transducer for multi-target micromanipulation. The gripper consists of three fingers assembled on adjustable pedestals with flexible hinges for a large adjustable range. Each finger has a PZT actuator, an amplifying structure, and a changeable end effector. The moving trajectories of single and double fingers were calculated and finite element analyses were performed to verify the reliability of the structures. In the gripping experiment, various end effectors of the fingers such as tungsten probes and fibers were tested, and different micro-objects such as glass hollow spheres and iron spheres with diameters ranging from 10 to 800 μm were picked and released. The output resolution is 145 nm/V, and the driven displacement range of the gripper is 43.4 μm. The PZT actuated triple-finger gripper has superior adaptability, high efficiency, and a low cost.

Texture variations in sol-gel derived PZT films on substrates with platinum metallization

NARCIS (Netherlands)

Gardeniers, Johannes G.E.; Elwenspoek, Michael Curt; Cobianu, C.

1994-01-01

Metalorganic precursor solutions of composition Zr : Ti = 0.53 : 0.47 were used to spin-cast PZT layers on sputtered Pt films. After annealing at temperatures of 550 °C - 800 °C, the PZT films of tetragonal perovskite structure reproducibly showed different textures and surface morphologies,

Characterization of lead zirconate titanate (PZT)--indium tin oxide (ITO) thin film interface

International Nuclear Information System (INIS)

Sreenivas, K.; Sayer, M.; Laursen, T.; Whitton, J.L.; Pascual, R.; Johnson, D.J.; Amm, D.T.

1990-01-01

In this paper the interface between ultrathin sputtered lead zirconate titanate (PZT) films and a conductive electrode (indium tin oxide-ITO) is investigated. Structural and compositional changes at the PZT-ITO interface have been examined by surface analysis and depth profiling techniques of glancing angle x-ray diffraction, Rutherford backscattering (RBS), SIMS, Auger electron spectroscopy (AES), and elastic recoil detection analysis (ERDA). Studies indicate significant interdiffusion of lead into the underlying ITP layer and glass substrate with a large amount of residual stress at the interface. Influence of such compositional deviations at the interface is correlated to an observed thickness dependence in the dielectric properties of PZT films

Dielectric and Piezoelectric Properties of PZT Composite Thick Films with Variable Solution to Powder Ratios.

Science.gov (United States)

Wu, Dawei; Zhou, Qifa; Shung, Koping Kirk; Bharadwaja, Srowthi N; Zhang, Dongshe; Zheng, Haixing

2009-05-08

The use of PZT films in sliver-mode high-frequency ultrasonic transducers applications requires thick, dense, and crack-free films with excellent piezoelectric and dielectric properties. In this work, PZT composite solutions were used to deposit PZT films >10 μm in thickness. It was found that the functional properties depend strongly on the mass ratio of PZT sol-gel solution to PZT powder in the composite solution. Both the remanent polarization, P(r), and transverse piezoelectric coefficient, e(31,) (f), increase with increasing proportion of the sol-gel solution in the precursor. Films prepared using a solution-to-powder mass ratio of 0.5 have a remanent polarization of 8 μC/cm(2), a dielectric constant of 450 (at 1 kHz), and e(31,) (f) = -2.8 C/m(2). Increasing the solution-to-powder mass ratio to 6, the films were found to have remanent polarizations as large as 37 μC/cm(2), a dielectric constant of 1250 (at 1 kHz) and e(31,) (f) = -5.8 C/m(2).

Fabrication and Characterization of PZT Thick Films for Sensing and Actuation

Directory of Open Access Journals (Sweden)

Kuo-Ching Kuo

2007-04-01

Full Text Available Lead Zirconate Titanate oxide (PZT thick films with thicknesses of up to 10 μmwere developed using a modified sol-gel technique. Usually, the film thickness is less than1 μm by conventional sol-gel processing, while the electrical charge accumulation whichreveals the direct effect of piezoelectricity is proportional to the film thickness and thereforerestricted. Two approaches were adopted to conventional sol-gel processing – precursorconcentration modulation and rapid thermal annealing. A 10 μm thick film was successfullyfabricated by coating 16 times via this technique. The thickness of each coating layer wasabout 0.6 μm and the morphology of the film was dense with a crack-free area as large as 16mm2. In addition, the structure, surface morphology and physical properties werecharacterized by X-ray diffraction (XRD, scanning electron microscopy (SEM and atomicforce microscopy (AFM and electrical performance. The dielectric constant and hysteresisloops were measured as electric characteristics. This study investigates the actuation andsensing performance of the vibrating structures with the piezoelectric thick film. Theactuation tests demonstrated that a 4 mm x 4 mm x 6.5 μm PZT film drove a 40 mm x 7 mmx 0.5 mm silicon beam as an actuator. Additionally, it generated an electrical signal of 60mVpp as a sensor, while vibration was input by a shaker. The frequencies of the first twomodes of the beam were compared with the theoretical values obtained by Euler-Bernoullibeam theory. The linearity of the actuation and sensing tests were also examined.

Modeling and Analysis of a Bimorph PZT Cantilever Beam Based Micropower Generator

Directory of Open Access Journals (Sweden)

Jyoti AJITSARIA

2009-06-01

Full Text Available Recent developments in miniaturized sensors, digital processors and wireless communication systems have many desirable applications. The realization of these applications however, is limited by the lack of a similarly sized power source. One method of power harvesting is the use of piezoelectric materials (PZT, which form transducers that are able to interchange electrical energy and mechanical vibration. Many proposed power generation systems employ a piezoelectric component to convert the mechanical energy to electrical energy. In this paper, a formulation of mathematical model is developed that predicts the power conversion for a device that contains a piezoelectric component. Analysis is also done with AC/DC power conversion using a bridge rectifier circuit. Finally, the verification of the models is performed experimentally and comparison has been made with the simulation results. The comparison of simulation results coincide with experimental data quite well.

Sensitivity Enhancement in Magnetic Sensors Based on Ferroelectric-Bimorphs and Multiferroic Composites

Directory of Open Access Journals (Sweden)

Gollapudi Sreenivasulu

2016-02-01

Full Text Available Multiferroic composites with ferromagnetic and ferroelectric phases have been studied in recent years for use as sensors of AC and DC magnetic fields. Their operation is based on magneto-electric (ME coupling between the electric and magnetic subsystems and is mediated by mechanical strain. Such sensors for AC magnetic fields require a bias magnetic field to achieve pT-sensitivity. Novel magnetic sensors with a permanent magnet proof mass, either on a ferroelectric bimorph or a ferromagnetic-ferroelectric composite, are discussed. In both types, the interaction between the applied AC magnetic field and remnant magnetization of the magnet results in a mechanical strain and a voltage response in the ferroelectric. Our studies have been performed on sensors with a Nd-Fe-B permanent magnet proof mass on (i a bimorph of oppositely-poled lead zirconate titanate (PZT platelets and (ii a layered multiferroic composite of PZT-Metglas-Ni. The sensors have been characterized in terms of sensitivity and equivalent magnetic noise N. Noise N in both type of sensors is on the order of 200 pT/√Hz at 1 Hz, a factor of 10 improvement compared to multiferroic sensors without a proof mass. When the AC magnetic field is applied at the bending resonance for the bimorph, the measured N ≈ 700 pT/√Hz. We discuss models based on magneto-electro-mechanical coupling at low frequency and bending resonance in the sensors and theoretical estimates of ME voltage coefficients are in very good agreement with the data.

Sensitivity Enhancement in Magnetic Sensors Based on Ferroelectric-Bimorphs and Multiferroic Composites.

Science.gov (United States)

Sreenivasulu, Gollapudi; Qu, Peng; Petrov, Vladimir; Qu, Hongwei; Srinivasan, Gopalan

2016-02-20

Multiferroic composites with ferromagnetic and ferroelectric phases have been studied in recent years for use as sensors of AC and DC magnetic fields. Their operation is based on magneto-electric (ME) coupling between the electric and magnetic subsystems and is mediated by mechanical strain. Such sensors for AC magnetic fields require a bias magnetic field to achieve pT-sensitivity. Novel magnetic sensors with a permanent magnet proof mass, either on a ferroelectric bimorph or a ferromagnetic-ferroelectric composite, are discussed. In both types, the interaction between the applied AC magnetic field and remnant magnetization of the magnet results in a mechanical strain and a voltage response in the ferroelectric. Our studies have been performed on sensors with a Nd-Fe-B permanent magnet proof mass on (i) a bimorph of oppositely-poled lead zirconate titanate (PZT) platelets and (ii) a layered multiferroic composite of PZT-Metglas-Ni. The sensors have been characterized in terms of sensitivity and equivalent magnetic noise N. Noise N in both type of sensors is on the order of 200 pT/√Hz at 1 Hz, a factor of 10 improvement compared to multiferroic sensors without a proof mass. When the AC magnetic field is applied at the bending resonance for the bimorph, the measured N ≈ 700 pT/√Hz. We discuss models based on magneto-electro-mechanical coupling at low frequency and bending resonance in the sensors and theoretical estimates of ME voltage coefficients are in very good agreement with the data.

Synthesis and characterization of tungsten or calcium doped PZT ceramics

International Nuclear Information System (INIS)

Santos, D.M.; Caracas, L.B.; Noronha, R.G.; Santos, M.M.T. dos; Paiva-Santos, C.O.

2009-01-01

Pure and doped (tungsten or calcium) PZT ceramics were prepared by association of the polymeric precursor and partial oxalate method. The phase formation was investigated by thermal analysis (TG/DSC) and X-ray diffraction (XRD). The affect of W or Ca doping PZT and their electrical properties was evaluated. Substitution of W by Ti and Ca by Pb leads to an increase of Curie temperature and broadening of dielectric constant. A typical hysteresis loop was observed at room temperature and the remnant polarization was increased with the content of W and Ca. (author)

Passive Impact Damage Detection of Fiber Glass Composite Panels

Science.gov (United States)

2013-12-19

Another important reason to chose sensor embedding is that the composite layers prevent the electromechanical fatigue degradation of the PZT (Sung...15 Figure 3-1 PZT sensor used on this work. .................................................................................... 28 Figure 3-3 PZT ...are used to hold the PZT sensor. ........................ 29 Figure 3-5 A small amount of solder is applied to the sensor to connect the wire leads

Stacking effect on the ferroelectric properties of PZT/PLZT multilayer thin films formed by photochemical metal-organic deposition

International Nuclear Information System (INIS)

Park, Hyeong-Ho; Park, Hyung-Ho; Hill, Ross H.

2004-01-01

The ferroelectric properties of lead zirconate titanate (PZT) and lanthanum-doped lead zirconate titanate (PLZT) multilayer films formed by photochemical metal-organic deposition (PMOD) using photosensitive precursors have been characterized. The substitution of La for Pb was reported to induce improved ferroelectric properties, especially fatigue resistance, through the reduction of oxygen vacancies. The relation between La-substitution and the ferroelectric properties was investigated by characterization of the effect of the order of stacking four ferroelectric layers of PZT or PLZT in the multilayer films 4-PZT, PZT/2-PLZT/PZT, PLZT/2-PZT/PLZT, and 4-PLZT. The films with the PLZT layer at the top and bottom showed an improvement in the fatigue resistance. It was revealed that defect dipole such as O vacancy was reduced at the ferroelectric/Pt interface by doping with La. Also, the bottom layer, just on Pt substrate had a significant influence on the surface microstructure and growth orientation of ferroelectric film

Ultra-fast microwave sintering of PZT/FCO particulate composites prepared by ultrasonic mixing; Sinterizacao ultrarrapida por micro-ondas de compositos particulados PZT/FCO preparados por mistura em ultrassom

Energy Technology Data Exchange (ETDEWEB)

Fernandez, C.P.; Zabotto, F.L.; Garcia, D.; Kiminami, R.H.G.A. [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil)

2017-07-15

Pb(Zr{sub 0.53}Ti{sub 0.47})O{sub 3} (PZT) and Fe{sub 2}CoO{sub 4} (FCO) powders were synthesized separately by the Pechini method and then ultrasonically mixed in molar proportions of 80/20 and 50/50 of PZT/FCO. The resulting composites were pressed and subjected to conventional and ultrafast microwave-assisted sintering. The structure and microstructure of the sintered samples were analyzed, respectively, by X-ray diffraction and scanning electron microscopy. The dielectric constant as a function of temperature, electrical resistivity and magnetoelectric coupling coefficient were measured. The results indicated that the ultrasonic mixing method applied to PZT and FCO was fast and efficient, and that sintering resulted in globally connected (0-3) particulate composites and uniform distribution of the ferromagnetic phase (FCO) grains in the ferroelectric matrix (PZT). The structural analysis indicated that microwave sintering changed the arrangement (1-3) of the material's local connectivity, which was attributed to the intensification of diffusion processes that occur in this type of sintering, particularly in nanometric systems. The high values of resistivity indicated that although both sintering methods preserved the integrity of the two phases, microwave sintering was more efficient, ensuring the magnetoelectric behavior of all the composites under study. The values of H{sub max} field were dependent on the ferrite phase concentration and sintering; 80/20 1.4 and 1.9 kOe, and 50/50 3.5 and 3.0 kOe in the samples sintered by microwave and conventionally, consistent with the literature, which confirmed the integrity of the constituent phases PZT and FCO. (author)

Structure and properties of PZT thin films on strontium ruthenate and calcium ruthenate electrodes

International Nuclear Information System (INIS)

Wu, T.-J.; Tsai, D.-S.

2004-01-01

PZT thin films have been prepared via metalorganic CVD (MOCVD) on four substrates of conducting oxides of ruthenates, SrRuO 3 /Pt/Ti/SiO 2 /Si(1 0 0), SrRuO 3 /SiO 2 /Si(1 0 0), CaRuO 3 /Pt/Ti/SiO 2 /Si(1 0 0), CaRuO 3 /SiO 2 /Si(1 0 0). The conducting ruthenate layers were also grown using MOCVD. Ferroelectric properties of polarization fatigue and leakage current density are measured. The internal strain of PZT thin crystal which is mainly constrained by the bottom electrode seems to be the decisive factor in ferroelectric properties. The internal strain of PZT is represented by its tetragonality ratio. The PZT thin film in the capacitor Au/PZT/SrRuO 3 /Pt/Ti/SiO 2 /Si, with the largest tetragonality ratio 1.026, exhibits an optimum combination of large polarization, less fatigue, and low leakage current density. Both SrRuO 3 and CaRuO 3 are good diffusion barriers to prevent interdiffusion of cations between the ferroelectric and the electrode. The slightly higher intermixing at the CaRuO 3 -to-Pt/Ti interface is owing to the high annealing temperature needed in CaRuO 3 synthesis

Study of piezoelectric filler on the properties of PZT-PVDF composites

Science.gov (United States)

Matei, Alina; Å¢ucureanu, Vasilica; Vlǎzan, Paulina; Cernica, Ileana; Popescu, Marian; RomaniÅ£an, Cosmin

2017-12-01

The ability to obtain composites with desired functionalities is based on advanced knowledge of the processes synthesis and of the structure of piezoceramic materials, as well the incorporation of different fillers in selected polymer matrix. Polyvinylidene fluoride (PVDF) is a fluorinated polymer with excellent mechanical and electric properties, which it was chosen as matrix due to their applications in a wide range of industrial fields [1-4]. The present paper focuses on the development of composites based on PZT particles as filler obtained by conventional methods and PVDF as polymer matrix. The synthesis of PVDF-PZT composites was obtained by dispersing the ceramic powders in a solution of PVDF in N-methyl-pyrrolidone (NMP) under mechanical mixing and ultrasonication, until a homogenous mixture is obtained. The properties of the piezoceramic fillers before and after embedding into the polymeric matrix were investigated by Fourier transform infrared spectrometry, field emission scanning electron microscopy and X-ray diffraction. In the FTIR spectra, appear a large number of absorption bands which are exclusive of the phases from PVDF matrix confirming the total embedding of PZT filler into matrix. Also, the XRD pattern of the composites has confirmed the presence of crystalline phases of PVDF and the ceramic phase of PZT. The SEM results showed a good distribution of fillers in the matrix.

Effect of Bi doping on morphotropic phase boundary and dielectric properties of PZT

Energy Technology Data Exchange (ETDEWEB)

Joshi, Shraddha; Acharya, Smita, E-mail: saha275@yahoo.com [Advanced Materials Research Laboratory, Department of Physics, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur-440033, M.S. India (India)

2016-05-23

In our present attempt, Pb{sub (1-x)}Bi{sub x}Zr{sub 0.52}Ti{sub 0.48}O{sub 3} [PBZT] {where x = 0, 0.05, 0.1} is synthesized by sol-gel route. Effect of Bi addition on structure, sinterability and dielectric properties are observed. The presence of morphotropic phase boundary (coexistence of tetragonal and rhombohedral symmetry) is confirmed by X-ray diffraction. Enhancement of sinterability after Bi doping is observed through a systematic sintering program. Frequency and temperature dependent dielectric constant are studied. Bi doping in PZT is found to enhance room temperature dielectric constant. However, at high temperature the dielectric constant of pure PZT is more than that of doped PZT.

Quantification of temperature effect on impedance monitoring via PZT interface for prestressed tendon anchorage

Science.gov (United States)

Huynh, Thanh-Canh; Kim, Jeong-Tae

2017-12-01

In this study, the quantification of temperature effect on impedance monitoring via a PZT interface for prestressed tendon-anchorage is presented. Firstly, a PZT interface-based impedance monitoring technique is selected to monitor impedance signatures by predetermining sensitive frequency bands. An analytical model is designed to represent coupled dynamic responses of the PZT interface-tendon anchorage system. Secondly, experiments on a lab-scaled tendon anchorage are described. Impedance signatures are measured via the PZT interface for a series of temperature and prestress-force changes. Thirdly, temperature effects on measured impedance responses of the tendon anchorage are estimated by quantifying relative changes in impedance features (such as RMSD and CCD indices) induced by temperature variation and prestress-force change. Finally, finite element analyses are conducted to investigate the mechanism of temperature variation and prestress-loss effects on the impedance responses of prestressed tendon anchorage. Temperature effects on impedance monitoring are filtered by effective frequency shift-based algorithm for distinguishing prestress-loss effects on impedance signatures.

The influence of preferred orientation and poling temperature on the polarization switching current in PZT thin films

Energy Technology Data Exchange (ETDEWEB)

Xiao, Mi; Zhang, Weikang; Zhang, Zebin; Zhang, Ping [Tianjin University, School of Electrical and Information Engineering, Tianjin (China); Lan, Kuibo [Tianjin University, School of Microelectronics, Tianjin (China)

2017-07-15

In this paper, Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3} (PZT) thin films with different preferred orientation were prepared on platinized silicon substrates by a modified sol-gel method. Our results indicate that the polarization switching current in PZT thin films is dependent on preferred orientation and poling temperature. In our measurements, (111)-oriented PZT has a larger polarization switching current than randomly oriented PZT, and with the increase of the degree of (111) preferred orientation and the poling temperature, the polarization switching current gradually increase. Considering the contact of PZT thin film with electrodes, the space-charged limited conduction (SCLC) combined with domain switching mechanism may be responsible for such phenomena. By analyzing the conduction data, we found the interface-limited Schottky emission (ES) and bulk-limited Poole-Frenkel hopping (PF) are not suitable for our samples. (orig.)

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

Directory of Open Access Journals (Sweden)

Yingwei Li

Full Text Available 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.

1.6 V nanogenerator for mechanical energy harvesting using PZT nanofibers.

Science.gov (United States)

Chen, Xi; Xu, Shiyou; Yao, Nan; Shi, Yong

2010-06-09

Energy harvesting technologies that are engineered to miniature sizes, while still increasing the power delivered to wireless electronics, (1, 2) portable devices, stretchable electronics, (3) and implantable biosensors, (4, 5) are strongly desired. Piezoelectric nanowire- and nanofiber-based generators have potential uses for powering such devices through a conversion of mechanical energy into electrical energy. (6) However, the piezoelectric voltage constant of the semiconductor piezoelectric nanowires in the recently reported piezoelectric nanogenerators (7-12) is lower than that of lead zirconate titanate (PZT) nanomaterials. Here we report a piezoelectric nanogenerator based on PZT nanofibers. The PZT nanofibers, with a diameter and length of approximately 60 nm and 500 microm, were aligned on interdigitated electrodes of platinum fine wires and packaged using a soft polymer on a silicon substrate. The measured output voltage and power under periodic stress application to the soft polymer was 1.63 V and 0.03 microW, respectively.

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

Science.gov (United States)

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.

Effect of solid content variations on PZT slip for tape casting

Directory of Open Access Journals (Sweden)

Gang Jian

2012-12-01

Full Text Available Lead zirconate titanate (PZT particles with pure tetragonal structure were synthesized by solid-state reaction method and used for preparation of slurries with different solid contents (34–80 wt.%. Then, PZT thick films were fabricated by the nonaqueous tape casting method. It was shown that the slurry prepared from ball-milled particles exhibited better rheology properties than slurry from particles which were not ball-milled. Measurement of sedimentation volumes and zeta potentials indicated particle aggregation, resulting in weak stability of the slurries with high solid contents. The microstructure, piezoelectric and ferroelectric properties of PZT sintered films were investigated in terms of solid contents. Ceramic films prepared from the slurry with solid contents of 73 wt.% had the optimal structure and properties. After poling at 200 °C with an applied field of 1.2 kV/cm, a d33 of 294 pC/N was achieved; typical ferroelectric properties were also observed with a Ps of 38 μC/cm2.

Niobium effect on the Pzt ceramic properties; Efeito do niobio sobre as propriedades da ceramica PZT

Energy Technology Data Exchange (ETDEWEB)

Gimenes, R.; Zaguete, M.A.; Varela, J.A.; Cilense, M.; Paiva-Santos, C.O.; Las, W.C. [UNESP, Araraquara, SP (Brazil). Inst. de Quimica

1996-12-31

Lead zirconate titanate, PZT, was prepared with Zr/Ti ratio of 50/50. The powder was prepared by the Pechini method with addition of 0,3; 0,5 e 0,7 mol % of Nb{sup +5} ions. The precursors obtained were calcined at 700 deg C for 3 hs and milled with zirconia balls in a medium of isopropilic alcohol for 6 hs. The powders were characterized by XRD. For the sintering studies powders were isostatically pressed (230 MPa) into pellets and which were put inside a box furnace at 1200 deg C for 2 hs and 1100 deg C for 4 hs in a closed system containing 5 % of atmospheric powder (Pb Zr O{sub 3} + 5% Pb O) relative to all pellets`mass. It was verified that the best densification rate was obtained for PZT with addition of 0,5 mol % of Nb{sup +5} ions and sintered at 1100 deg C for 4 hs. Sintered samples at 1100 deg C for 4 hs were characterized as to dielectric (k, P{sub r} and E{sub c}) and piezoelectric properties. (author) 5 refs., 2 figs., 3 tabs.

Single ZnO nanowire-PZT optothermal field effect transistors.

Science.gov (United States)

Hsieh, Chun-Yi; Lu, Meng-Lin; Chen, Ju-Ying; Chen, Yung-Ting; Chen, Yang-Fang; Shih, Wan Y; Shih, Wei-Heng

2012-09-07

A new type of pyroelectric field effect transistor based on a composite consisting of single zinc oxide nanowire and lead zirconate titanate (ZnO NW-PZT) has been developed. Under infrared (IR) laser illumination, the transconductance of the ZnO NW can be modulated by optothermal gating. The drain current can be increased or decreased by IR illumination depending on the polarization orientation of the Pb(Zr(0.3)Ti(0.7))O(3) (PZT) substrate. Furthermore, by combining the photocurrent behavior in the UV range and the optothermal gating effect in the IR range, the wide spectrum of response of current by light offers a variety of opportunities for nanoscale optoelectronic devices.

Improvement in fatigue property for a PZT ferroelectric film device with SRO electrode film prepared by chemical solution deposition

International Nuclear Information System (INIS)

Miyazaki, H.; Miwa, Y.; Suzuki, H.

2007-01-01

PZT films with (1 0 0) and (1 1 0) orientation were prepared by spin coating using the chemical solution deposition (CSD) method on an SRO/Si or a Pt/Ti/SiO 2 /Si substrate. The remnant polarization and the saturation polarization of the PZT/SRO/Si film were 21 and 35 μC/cm 2 , and those of the PZT/Pt/Ti/SiO 2 /Si film were 20 and 31 μC/cm 2 . The remnant polarization of the PZT/SRO/Si film maintained more than 10 8 switching cycles, and the fatigue property was observed for the PZT film fabricated on the Pt/Ti/SiO 2 /Si electrode

PZT Thin Film Piezoelectric Traveling Wave Motor

Science.gov (United States)

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.

Structural and electrical characterization of PZT on gold for micromachined piezoelectric membranes

International Nuclear Information System (INIS)

Robinson, M.C.; Morris, D.J.; Hayenga, P.D.; Cho, J.H.; Richards, C.D.; Richards, R.F.; Bahr, D.F.

2006-01-01

Piezoelectric membranes have been fabricated that incorporate a gold bottom electrode with an adhesion layer of titanium-tungsten (10:90 wt. %). For solution-deposited acetic acid based lead zirconate titanate (HoAc-PZT) with a Zr:Ti ratio of 40:60, the film's average piezoelectric coefficient, e 31 , is -5.31 C/m 2 , with a dielectric constant of 814 at 200 Hz, which is similar to values for platinum bottom electrodes. The PZT structure remains columnar on both types of bottom electrodes. Initial fabrication attempts resulted in cracking that initiated in the PZT layer of the structure. X-ray photoelectron spectroscopy was utilized to establish how processing affects diffusion throughout the composite membrane structure. Crack-free membranes were fabricated and tested. This paper discusses the performance properties and piezoelectric fatigue results for these membranes. (orig.)

Effect of the Sr and Fe incorporation on the Pzt electric and ceramic properties; Efeito da incorporacao de Sr e Fe nas propriedades ceramicas e eletricas de PZT

Energy Technology Data Exchange (ETDEWEB)

Santos, Marcia C. Cavaco dos [Instituto de Pesquisas da Marinha, Rio de Janeiro, RJ (Brazil); Villegas, Marina; Moure, Carlos [Instituto de Ceramica e Vidro, Madrid (Spain)

1997-12-31

The Piezoelectric Pzt properties with compositions near of morphotropic boundary phase can be usefully modified by adding small quantities of various oxides, such as, Fe{sub 2} O{sub 3} and Sr O, which Fe{sub 2} O{sub 3} has been studied due his property of decrease the Dielectric Loss factor and increase the Mechanical Quality Factor of PZT Ceramics. With this purpose a powder was synthesized through an organic precursors route, where a finely divided powder, with a good PZT phase formation at low temperatures. The electrical properties of temperatures. The electrical properties of the [Pb{sub 0.9.8} Sr 0{sub .53} Ti{sub o.4676} Fe{sub 0.00024} {sub 03}] compositions with 1% of Pb O excess confirmed the Fe{sub 2} (O{sub 3}) additive performance, counterbalancing with Sr O effects. (author) 7 refs., 5 figs., 3 tabs.

Structural Contribution to the Ferroelectric Fatigue in Lead Zirconate Titanate (PZT) Ceramics

OpenAIRE

Hinterstein , Manuel; Rouquette , Jerome; Haines , J; Papet , Ph; Glaum , Julia; Knapp , Michael; Eckert , J; Hoffman , M

2014-01-01

International audience; Many ferroelectric devices are based on doped lead zirconate titanate (PZT) ceramics with compositions near the morphotropic phase boundary (MPB), at which the relevant material's properties approach their maximum. Based on a synchrotron x-ray diffraction study of MPB PZT, bulk fatigue is unambiguously found to arise from a less effective field induced tetragonal-to-monoclinic transformation, at which the degradation of the polarization flipping is detected by a less i...

Development of a wireless nonlinear wave modulation spectroscopy (NWMS) sensor node for fatigue crack detection

Science.gov (United States)

Liu, Peipei; Yang, Suyoung; Lim, Hyung Jin; Park, Hyung Chul; Ko, In Chang; Sohn, Hoon

2014-03-01

Fatigue crack is one of the main culprits for the failure of metallic structures. Recently, it has been shown that nonlinear wave modulation spectroscopy (NWMS) is effective in detecting nonlinear mechanisms produced by fatigue crack. In this study, an active wireless sensor node for fatigue crack detection is developed based on NWMS. Using PZT transducers attached to a target structure, ultrasonic waves at two distinctive frequencies are generated, and their modulation due to fatigue crack formation is detected using another PZT transducer. Furthermore, a reference-free NWMS algorithm is developed so that fatigue crack can be detected without relying on history data of the structure with minimal parameter adjustment by the end users. The algorithm is embedded into FPGA, and the diagnosis is transmitted to a base station using a commercial wireless communication system. The whole design of the sensor node is fulfilled in a low power working strategy. Finally, an experimental verification has been performed using aluminum plate specimens to show the feasibility of the developed active wireless NWMS sensor node.

Phase and electrical properties of PZT thin films embedded with CuO nano-particles by a hybrid sol-gel route

Science.gov (United States)

Sreesattabud, Tharathip; Gibbons, Brady J.; Watcharapasorn, Anucha; Jiansirisomboon, Sukanda

2013-07-01

Pb(Zr0.52Ti0.48)O3 or PZT thin films embedded with CuO nano-particles were successfully prepared by a hybrid sol-gel process. In this process, CuO (0, 0.1, 0.2, 0.3, 0.4, 0.5 and 1 wt. %) nanopowder was suspended in an organometallic solution of PZT, and then coated on platinised silicon substrate using a spin-coating technique. The influence of CuO nano-particles' dispersion on the phase of PZT thin films was investigated. XRD results showed a perovskite phase in all films. At the CuO concentration of 0.4-1 wt. %, a second phase was observed. The addition of CuO nano-particles affected the orientation of PZT thin films. The addition was also found to reduce the ferroelectric properties of PZT thin films. However, at 0.2 wt. % CuO concentration, the film exhibited good ferroelectric properties similar to those of PZT films. In addition, the fatigue retention properties of the PZT/CuO system was observed, and it showed 14% fatigue at 108 switching bipolar pulse cycles while the fatigue in PZT thin films was found to be 17% at the same switching bipolar pulse cycles.

Piezoelectric ceramic (PZT) modulates axonal guidance growth of rat cortical neurons via RhoA, Rac1, and Cdc42 pathways.

Science.gov (United States)

Wen, Jianqiang; Liu, Meili

2014-03-01

Electrical stimulation is critical for axonal connection, which can stimulate axonal migration and deformation to promote axonal growth in the nervous system. Netrin-1, an axonal guidance cue, can also promote axonal guidance growth, but the molecular mechanism of axonal guidance growth under indirect electric stimulation is still unknown. We investigated the molecular mechanism of axonal guidance growth under piezoelectric ceramic lead zirconate titanate (PZT) stimulation in the primary cultured cortical neurons. PZT induced marked axonal elongation. Moreover, PZT activated the excitatory postsynaptic currents (EPSCs) by increasing the frequency and amplitude of EPSCs of the cortical neurons in patch clamp assay. PZT downregulated the expression of Netrin-1 and its receptor Deleted in Colorectal Cancer (DCC). Rho GTPase signaling is involved in interactions of Netrin-1 and DCC. PZT activated RhoA. Dramatic decrease of Cdc42 and Rac1 was also observed after PZT treatment. RhoA inhibitor Clostridium botulinum C3 exoenzyme (C3-Exo) prevented the PZT-induced downregulation of Netrin-1 and DCC. We suggest that PZT can promote axonal guidance growth by downregulation of Netrin-1 and DCC to mediate axonal repulsive responses via the Rho GTPase signaling pathway. Obviously, piezoelectric materials may provide a new approach for axonal recovery and be beneficial for clinical therapy in the future.

A Piezoelectric PZT Ceramic Mulitlayer Stack for Energy Harvesting Under Dynamic Forces

Science.gov (United States)

Xu, Tian-Bing; Siochi, Emilie J.; Kang, Jin Ho; Zuo, Lei; Zhou, Wanlu; Tang, Xiudong; Jiang, Xiaoning

2011-01-01

Piezoelectric energy harvesting transducers (PEHTs) are commonly used in motion/vibration energy scavenging devices. To date, most researchers have focused on energy harvesting at narrow bandwidths around the mechanical resonance frequency, and most piezoelectric harvesting devices reported in the literature have very low effective piezoelectric coefficient (d(sub eff)) (PZT ceramic multilayer stack (PZT-Stack) with high effective piezoelectric coefficient for high-performance PEHTs. The PZT-Stack is composed of 300 layers of 0.1 mm thick PZT plates, with overall dimensions of 32.4 mm X 7.0 mm X 7.0 mm. Experiments were carried out with dynamic forces in a broad bandwidth ranging from 0.5 Hz to 25 kHz. The measured results show that the effective piezoelectric coefficient of the PZT-stack is about 1 X 10(exp 5) pC/N at off-resonance frequencies and 1.39 X 10(exp 6) pC/N at resonance, which is order of magnitude larger than that of traditional PEHTs. The effective piezoelectric coefficients (d(sub eff)) do not change significantly with applied dynamic forces having root mean square (RMS) values ranging from 1 N to 40 N. In resonance mode, 231 mW of electrical power was harvested at 2479 Hz with a dynamic force of 11.6 N(sub rms), and 7.6 mW of electrical power was generated at a frequency of 2114 Hz with 1 N(sub rms) dynamic force. In off-resonance mode, an electrical power of 18.7 mW was obtained at 680 Hz with a 40 N(sub rms) dynamic force. A theoretical model of energy harvesting for the PZT-Stack is established. The modeled results matched well with experimental measurements. This study demonstrated that high effective piezoelectric coefficient structures enable PEHTs to harvest more electrical energy from mechanical vibrations or motions, suggesting an effective design for high-performance low-footprint PEHTs with potential applications in military, aerospace, and portable electronics. In addition, this study provides a route for using piezoelectric multilayer

Temperature dependence of PZT film optical properties

Czech Academy of Sciences Publication Activity Database

Deineka, Alexander; Jastrabík, Lubomír; Suchaneck, G.; Gerlach, G.

11-12, - (2001), s. 352-354 ISSN 0447-6441 R&D Projects: GA ČR GA202/00/1425; GA MŠk LN00A015 Institutional research plan: CEZ:AV0Z1010914 Keywords : refractive index profile * PZT film * temperature dependence of optical properties Subject RIV: BH - Optics, Masers, Lasers

In-situ structural investigations of ferroelasticity in soft and hard rhombohedral and tetragonal PZT

Energy Technology Data Exchange (ETDEWEB)

Morozov, Maxim I., E-mail: maximm@alumni.ntnu.no; Einarsrud, Mari-Ann; Tolchard, Julian R.; Grande, Tor [Department of Materials Science and Engineering, Norwegian University of Science and Technology, NO-7491 Trondheim (Norway); Geiger, Philipp T.; Webber, Kyle G. [Department of Materials Science, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen (Germany); Damjanovic, Dragan [Ceramics Laboratory, Swiss Federal Institute of Technology in Lausanne-EPFL, 1015 Lausanne (Switzerland)

2015-10-28

Despite the technological importance of hard and soft PZT, Pb(Zr,Ti)O{sub 3}, ceramics, the mechanisms of ferroelectric hardening and softening remain widely discussed in the literature. The hardening and softening phenomena have traditionally been investigated in relation with dielectric manifestations such as aging of the dielectric susceptibility and constriction of the polarization-electric field hysteresis loop. Here, we present a systematic investigation of the ferroelectric and ferroelastic properties of soft and hard PZT in both the tetragonal and rhombohedral phases. A particular focus has been devoted to ferroelastic domain switching by characterizing the macroscopic mechanical constitutive behavior and in-situ synchrotron X-ray diffraction during compression. It is demonstrated that variation of the ordering state of point defects in PZT ceramics affects the switching behavior of both ferroelectric and ferroelastic domains under mechanical or electrical fields. Softening of the mechanical and electrical properties of originally hard PZT ceramics was conferred by quenching the materials from above the Curie temperature. The present findings are discussed with respect to the current understanding of hardening-softening transitions in ferroelectric materials.

Parametric study on a collocated PZT beam vibration absorber and power harvester

Energy Technology Data Exchange (ETDEWEB)

Huang, Shyh Chin [Mechanical Engineering, Ming Chi University of Technology, New Taipei (China); Tsai, Chao Yang [Mechanical Engineering Army Academy, R.O.C., Taoyuan (China); Liao, Hsiao Hui [LNG Construction and Project Division, CPC Corp., Taipei (China)

2016-11-15

The parametric effects of a PZT beam that is simultaneously used as a vibration absorber and a power harvester were investigated in this study. A cantilever beam paved with PZT layers and with added tip mass has been widely used as a harvester or sometimes as a Dynamic vibration absorber (DVA). However, the beam is rarely considered a collocated device. In this study, the first step was theoretical derivation of a distributed beam covered with bimorph PZT layers. Then, the beam was attached to a 1DOF vibratory main system. Two indicators for vibration absorption and power harvesting were defined. Numerical results demonstrated that the lumped mass ratio favored both of the abilities, but that the DVA mass ratio influenced these two abilities in exactly the opposite way. The conjunction of a harvester circuit into a DVA shifted its resonance frequency up to 5 % (an extreme case of open circuit R→∞). Simultaneous power harvesting diminished the absorption capability up to 35 % for each set of mass ratios. To achieve the maximum degree of power harvesting, a corresponding load resistance that somewhat increases with the lumped mass ratio is applied. Experimental results verified the existence of the best load resistance, but the measured harvested curve was lower than the theoretical calculation because of structure damping and deviations of PZT material properties.

Parametric study on a collocated PZT beam vibration absorber and power harvester

International Nuclear Information System (INIS)

Huang, Shyh Chin; Tsai, Chao Yang; Liao, Hsiao Hui

2016-01-01

The parametric effects of a PZT beam that is simultaneously used as a vibration absorber and a power harvester were investigated in this study. A cantilever beam paved with PZT layers and with added tip mass has been widely used as a harvester or sometimes as a Dynamic vibration absorber (DVA). However, the beam is rarely considered a collocated device. In this study, the first step was theoretical derivation of a distributed beam covered with bimorph PZT layers. Then, the beam was attached to a 1DOF vibratory main system. Two indicators for vibration absorption and power harvesting were defined. Numerical results demonstrated that the lumped mass ratio favored both of the abilities, but that the DVA mass ratio influenced these two abilities in exactly the opposite way. The conjunction of a harvester circuit into a DVA shifted its resonance frequency up to 5 % (an extreme case of open circuit R→∞). Simultaneous power harvesting diminished the absorption capability up to 35 % for each set of mass ratios. To achieve the maximum degree of power harvesting, a corresponding load resistance that somewhat increases with the lumped mass ratio is applied. Experimental results verified the existence of the best load resistance, but the measured harvested curve was lower than the theoretical calculation because of structure damping and deviations of PZT material properties

INVESTIGATION OF THE FREQUENCY-TEMPERATURE RELATIONSHIP OF THE DIELECTRIC PERMITTIVITY OF THE PZT PIEZOCERAMICS IN THE LOW FREQUENCY RANGE

Directory of Open Access Journals (Sweden)

A. I. ZOLOTAREVSKIY

2018-05-01

Full Text Available Purpose. To investigate the frequency-temperature relationship of the dielectric permittivity of PZT piezoceramics in the low frequency range. Methodology. To obtain the frequency-temperature relationship of the dielectric permittivity of the PZT piezoceramics, a technique was used to determine the capacitance of the capacitor, between which plates the sample was placed. The value of the dielectric permittivity of the sample was calculated from the capacitor capacitance obtained. Findings. The frequency-temperature relationship of the dielectric permittivity of the PZT piezoceramics in the low frequency range has been obtained by the authors. The dielectric permittivity is not practically related to the frequency of the alternating voltage at a low temperature, with increasing in temperature its value increases and frequency relationship is observed. The temperature relationship of the dielectric permittivity of the PZT piezoceramics is satisfactorily described by the exponential functional dependence in the low-temperature range. The activation energy of the PZT piezoceramics polarization is determined from the graph of the dependence of the logarithm of the dielectric permittivity upon the inverse temperature. Different values of the activation energy for the two temperature regions prove on the existence of different mechanisms of the PZT piezoceramics polarization in the temperature range being investigated. Originality. The authors investigated the frequency-temperature relationship of the dielectric permittivity of the PZT piezoceramics in the low-frequency range. It is established that the temperature relationship of the dielectric permittivity of the PZT piezoceramics is satisfactorily described by an exponential functional relationship in the lowtemperature range. The activation energy of polarization is determined for two temperature sections. Practical value. The research results can be used to study the mechanism of polarization of

Fabry-Perot Diaphragm Fiber Optic Sensor (DFOS for Acoustic Detection

Directory of Open Access Journals (Sweden)

Yan SUN

2007-10-01

Full Text Available A diaphragm fiber optic sensor (DFOS solely based on Fabry-Perot multiple beam interference has been designed and fabricated with micro-electric mechanical system (MEMS technology. The silicon diaphragm with an embossed center was designed with an interference gap width kept accurately. The DFOS was verified to be a truly and purely Fabry-Perot device via a critical test. Parallel testing with a Piezoelectric (PZT sensor showed that the DFOS had high sensitivity. The Fabry-Perot DFOS also demonstrated excellent performance in on-line monitoring of Partial Discharge (PD in power transformers.

Enhanced off-resonance magnetoelectric response in laser annealed PZT thick film grown on magnetostrictive amorphous metal substrate

Energy Technology Data Exchange (ETDEWEB)

Palneedi, Haribabu [Materials Interface Laboratory, Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701 (Korea, Republic of); Functional Ceramics Group, Korea Institute of Materials Science (KIMS), Changwon 641-831 (Korea, Republic of); Maurya, Deepam; Priya, Shashank [Bio-inspired Materials and Devices Laboratory (BMDL), Center for Energy Harvesting Materials and Systems (CEHMS), Virginia Tech, Blacksburg, Virginia 24061 (United States); Kim, Gi-Yeop; Choi, Si-Young, E-mail: youngchoi@kims.re.kr [Materials Modeling and Characterization Department, Korea Institute of Materials Science (KIMS), Changwon 641-831 (Korea, Republic of); Kang, Suk-Joong L. [Materials Interface Laboratory, Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701 (Korea, Republic of); Kim, Kwang-Ho [School of Materials Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Ryu, Jungho, E-mail: jhryu@kims.re.kr [Functional Ceramics Group, Korea Institute of Materials Science (KIMS), Changwon 641-831 (Korea, Republic of)

2015-07-06

A highly dense, 4 μm-thick Pb(Zr,Ti)O{sub 3} (PZT) film is deposited on amorphous magnetostrictive Metglas foil (FeBSi) by granule spray in vacuum process at room temperature, followed by its localized annealing with a continuous-wave 560 nm ytterbium fiber laser radiation. This longer-wavelength laser radiation is able to anneal the whole of thick PZT film layer without any deteriorative effects, such as chemical reaction and/or atomic diffusion, at the interface and crystallization of amorphous Metglas substrate. Greatly enhanced dielectric and ferroelectric properties of the annealed PZT are attributed to its better crystallinity and grain growth induced by laser irradiation. As a result, a colossal off-resonance magnetoelectric (ME) voltage coefficient that is two orders of magnitude larger than previously reported output from PZT/Metglas film-composites is achieved. The present work addresses the problems involved in the fabrication of PZT/Metglas film-composites and opens up emerging possibilities in employing piezoelectric materials with low thermal budget substrates (suitable for integrated electronics) and designing laminate composites for ME based devices.

Recent Progress on PZT Based Piezoelectric Energy Harvesting Technologies

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Min-Gyu Kang

2016-02-01

Full Text Available Energy harvesting is the most effective way to respond to the energy shortage and to produce sustainable power sources from the surrounding environment. The energy harvesting technology enables scavenging electrical energy from wasted energy sources, which always exist everywhere, such as in heat, fluids, vibrations, etc. In particular, piezoelectric energy harvesting, which uses a direct energy conversion from vibrations and mechanical deformation to the electrical energy, is a promising technique to supply power sources in unattended electronic devices, wireless sensor nodes, micro-electronic devices, etc., since it has higher energy conversion efficiency and a simple structure. Up to now, various technologies, such as advanced materials, micro- and macro-mechanics, and electric circuit design, have been investigated and emerged to improve performance and conversion efficiency of the piezoelectric energy harvesters. In this paper, we focus on recent progress of piezoelectric energy harvesting technologies based on PbZrxTi1-xO3 (PZT materials, which have the most outstanding piezoelectric properties. The advanced piezoelectric energy harvesting technologies included materials, fabrications, unique designs, and properties are introduced to understand current technical levels and suggest the future directions of piezoelectric energy harvesting.

Investigation of optical pump on dielectric tunability in PZT/PT thin film by THz spectroscopy.

Science.gov (United States)

Ji, Jie; Luo, Chunya; Rao, Yunkun; Ling, Furi; Yao, Jianquan

2016-07-11

The dielectric spectra of single-layer PbTiO3 (PT), single-layer PbZrxTi1-xO3 (PZT) and multilayer PZT/PT thin films under an external optical field were investigated at room temperature by time-domain terahertz (THz) spectroscopy. Results showed that the real part of permittivity increased upon application of an external optical field, which could be interpreted as hardening of the soft mode and increasing of the damping coefficient and oscillator strength. Furthermore, the central mode was observed in the three films. Among the dielectric property of the three thin films studied, the tunability of the PZT/PT superlattice was the largest.

Niobium effect on the Pzt ceramic properties

International Nuclear Information System (INIS)

Gimenes, R.; Zaguete, M.A.; Varela, J.A.; Cilense, M.; Paiva-Santos, C.O.; Las, W.C.

1996-01-01

Lead zirconate titanate, PZT, was prepared with Zr/Ti ratio of 50/50. The powder was prepared by the Pechini method with addition of 0,3; 0,5 e 0,7 mol % of Nb +5 ions. The precursors obtained were calcined at 700 deg C for 3 hs and milled with zirconia balls in a medium of isopropilic alcohol for 6 hs. The powders were characterized by XRD. For the sintering studies powders were isostatically pressed (230 MPa) into pellets and which were put inside a box furnace at 1200 deg C for 2 hs and 1100 deg C for 4 hs in a closed system containing 5 % of atmospheric powder (Pb Zr O 3 + 5% Pb O) relative to all pellets'mass. It was verified that the best densification rate was obtained for PZT with addition of 0,5 mol % of Nb +5 ions and sintered at 1100 deg C for 4 hs. Sintered samples at 1100 deg C for 4 hs were characterized as to dielectric (k, P r and E c ) and piezoelectric properties. (author)

PZT piezoelectric films on glass for Gen-X imaging

Science.gov (United States)

Wilke, Rudeger H. T.; Trolier-McKinstry, Susan; Reid, Paul B.; Schwartz, Daniel A.

2010-09-01

The proposed adaptive optics system for the Gen-X telescope uses piezoelectric lead zirconate titanate (PZT) films deposited on flexible glass substrates. The low softening transition of the glass substrates imposes several processing challenges that require the development of new approaches to deposit high quality PZT thin films. Synthesis and optimization of chemical solution deposited 1 μm thick films of PbZr0.52Ti0.48O3 on small area (1 in2) and large area (16 in2) Pt/Ti/glass substrates has been performed. In order to avoid warping of the glass at temperatures typically used to crystallize PZT films ({700°C), a lower temperature, two-step crystallization process was employed. An {80 nm thick seed layer of PbZr0.30Ti0.70O3 was deposited to promote the growth of the perovskite phase. After the deposition of the seed layer, the films were annealed in a rapid thermal annealing (RTA) furnace at 550°C for 3 minutes to nucleate the perovskite phase. This was followed by isothermal annealing at 550°C for 1 hour to complete crystallization. For the subsequent PbZr0.52Ti0.48O3 layers, the same RTA protocol was performed, with the isothermal crystallization implemented following the deposition of three PbZr0.52Ti0.48O3 spin-coated layers. Over the frequency range of 1 kHz to 100 kHz, films exhibit relative permittivity values near 800 with loss tangents below 0.07. Hysteresis loops show low levels of imprint with coercive fields of 40-50 kV/cm in the forward direction and 50-70 kV/cm in the reverse direction. The remanent polarization varied from 25-35 μC/cm2 and e31,f values were approximately -5.0 C/m2. In scaling up the growth procedure to large area films, where warping becomes more pronounced due to the increased size of the substrate, the pyrolysis and crystallization conditions were performed in a box furnace to improve the temperature uniformity. By depositing films on both sides of the glass substrate, the tensile stresses are balanced, providing a

Advances in Lead-Free Piezoelectric Materials for Sensors and Actuators

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Jacob L. Jones

2010-03-01

Full Text Available Piezoelectrics have widespread use in today’s sensor and actuator technologies. However, most commercially available piezoelectric materials, e.g., Pb [ZrxTi1-x] O3 (PZT,are comprised of more than 60 weight percent lead (Pb. Dueto its harmful effects, there is a strong impetus to identify new lead-free replacement materials with comparable properties to those of PZT. This review highlights recent developments in several lead-free piezoelectric materials including BaTiO3, Na0.5Bi0.5TiO3, K0.5Bi0.5TiO3, Na0.5K0.5NbO3, and their solid solutions. The factors that contribute to strong piezoelectric behavior are described and a summary of the properties for the various systems is provided.

Electro-Caloric Properties of BT/PZT Multilayer Thin Films Prepared by Sol-Gel Method.

Science.gov (United States)

Kwon, Min-Su; Lee, Sung-Gap; Kim, Kyeong-Min

2018-09-01

In this study, Barium Titanate (BT)/Lead Zirconate Titanate (PZT) multilayer thin films were fabricated by the spin-coating method on Pt (200 nm)/Ti (10 nm) SiO2 (100 nm)/P-Si (100) substrates using BaTiO3 and Pb(Zr0.90Ti0.10)O3 metal alkoxide solutions. The coating and heating procedure was repeated several times to form the multilayer thin films. All of BT/PZT multilayer thin films show X-ray diffraction patterns typical to a polycrystalline perovskite structure and a uniform and void free grain microstructure. The thickness of the BT and PZT film by one-cycle of drying/sintering was approximately 50 nm and all of the films consisted of fine grains with a flat surface morphology. The electrocaloric properties of BT/PZT thin films were investigated by indirect estimation. The results showed that the temperature change ΔT can be calculated as a function of temperature using Maxwell's relation; the temperature change reaches a maximum value of ~1.85 °C at 135 °C under an applied electric field of 260 kV/cm.

Indirect Measurement of Energy Density of Soft PZT Ceramic Utilizing Mechanical Stress

Science.gov (United States)

Unruan, Muangjai; Unruan, Sujitra; Inkong, Yutthapong; Yimnirun, Rattikorn

2017-11-01

This paper reports on an indirect measurement of energy density of soft PZT ceramic utilizing mechanical stress. The method works analogous to the Olsen cycle and allows for a large amount of electro-mechanical energy conversion. A maximum energy density of 350 kJ/m3/cycle was found under 0-312 MPa and 1-20 kV/cm of applied mechanical stress and electric field, respectively. The obtained result is substantially higher than the results reported in previous studies of PZT materials utilizing a direct piezoelectric effect.

Effect of the Sr and Fe incorporation on the Pzt electric and ceramic properties

International Nuclear Information System (INIS)

Santos, Marcia C. Cavaco dos; Villegas, Marina; Moure, Carlos

1997-01-01

The Piezoelectric Pzt properties with compositions near of morphotropic boundary phase can be usefully modified by adding small quantities of various oxides, such as, Fe 2 O 3 and Sr O, which Fe 2 O 3 has been studied due his property of decrease the Dielectric Loss factor and increase the Mechanical Quality Factor of PZT Ceramics. With this purpose a powder was synthesized through an organic precursors route, where a finely divided powder, with a good PZT phase formation at low temperatures. The electrical properties of temperatures. The electrical properties of the [Pb 0.9.8 Sr 0 .53 Ti o.4676 Fe 0.00024 ) 03 ] compositions with 1% of Pb O excess confirmed the Fe 2 O 3 ) additive performance, counterbalancing with Sr O effects. (author)

TEMPLATE-ASSISTED FABRICATION AND DIELECTROPHORETIC MANIPULATION OF PZT MICROTUBES

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VLADIMÍR KOVAĽ

2012-09-01

Full Text Available Mesoscopic high aspect ratio ferroelectric tube structures of a diverse range of compositions with tailored physical properties can be used as key components in miniaturized flexible electronics, nano- and micro-electro-mechanical systems, nonvolatile FeRAM memories, and tunable photonic applications. They are usually produced through advanced “bottom-up” or “topdown” fabrication techniques. In this study, a template wetting approach is employed for fabrication of Pb(Zr0.52Ti0.48O3 (PZT microtubes. The method is based on repeated infiltration of precursor solution into macroporous silicon (Si templates at a sub-atmospheric pressure. Prior to crystallization at 750°C, free-standing tubes of a 2-μm outer diameter, extending to over 30 μm in length were released from the Si template using a selective isotropic-pulsed XeF2 reactive ion etching. To facilitate rapid electrical characterization and enable future integration process, directed positioning and aligning of the PZT tubes was performed by dielectrophoresis. The electric field-assisted technique involves an alternating electric voltage that is applied through pre-patterned microelectrodes to a colloidal suspension of PZT tubes dispersed in isopropyl alcohol. The most efficient biasing for the assembly of tubes across the electrode gap of 12 μm was a square wave signal of 5 Vrms and 10 Hz. By varying the applied frequency in between 1 and 10 Hz, an enhancement in tube alignment was obtained.

Nonlinear piezoelectricity in PZT ceramics for generating ultrasonic phase conjugate waves

Science.gov (United States)

Yamamoto; Kokubo; Sakai; Takagi

2000-03-01

We have succeeded in the generation of acoustic phase conjugate waves with nonlinear PZT piezoelectric ceramics and applied them to ultrasonic imaging systems. Our aim is to make a phase conjugator with 100% efficiency. For this purpose, it is important to clarify the mechanism of acoustic phase conjugation through nonlinear piezoelectricity. The process is explained by the parametric interaction via the third-order nonlinear piezoelectricity between the incident acoustic wave at angular frequency omega and the pump electric field at 2 omega. We solved the coupling equations including the third-ordered nonlinear piezoelectricity and theoretically derived the amplitude efficiency of the acoustic phase conjugation. We compared the efficiencies between the theoretical and experimental values for PZT ceramics with eight different compositions. Pb[(Zn1/3Nb2/3)(1 - x)Tix]O3 (X = 0.09, PZNT91/9) piezoelectric single crystals have been investigated for high-performance ultrasonic transducer application, because these have large piezoelectric constants, high electrical-mechanical coupling factors and high dielectric constants. We found that they have third-order nonlinear piezoelectric constants much larger than PZT and are hopeful that the material as a phase conjugator has over 100% efficiency.

A concept for the development of piezoceramic materials based on lead zirconate titanate (PZT). Part 2; Ein Entwicklungskonzept piezokeramischer Werkstoffe auf der Basis von Bleizirkonattitanat (PZT). Teil 2

Energy Technology Data Exchange (ETDEWEB)

Helke, G. [CeramTec AG, Lauf a.d. Pegnitz (Germany)

2002-07-01

Piezoceramic ceramics based on Lead Zircontate Titanate (PZT) show - within a relatively close Zr/Ti ratio range (close to the ratio 0.5/0.5) - extreme values for remanent polarization P{sub r} and the dielectric coefficient {epsilon}{sub 33}{sup {tau}}/{epsilon}{sub 0} as well as their corresponding piezoelectric coefficients. Remanent polarization P{sub t} can be directly correlated to the structural parameter {delta} (spontaneous deformation) and the domain mobility {eta}. PZT modification results from the substitution of isovalent or heterovalent ions, thereby taking ion radii and valency at the A and B sites of the perovskite-type lattice under consideration. The substitution of specific ions is the process used to develop new piezoceramic materials which is mainly applied to determine the values of specific parameters corresponding to technical requirements. (orig.) [German] Piezoelektrische Keramiken auf der Basis von Bleizirkonattitanat (PZT) weisen in einem relativ engen Bereich des Zr/Ti-Verhaeltnisses (nahe dem Verhaeltnis 0,5/0,5). Extremwerte der remanenten Polarisation P{sub r} und der Dielektrizitaetskonstanten {epsilon}{sub 33}{sup {tau}}/{epsilon}{sub 0} sowie der von ihnen abhaengigen piezoelektrischen Kenngroessen auf. Die remanente Polarisation P{sub r} laesst sich unmittelbar dem Strukturparameter {delta} (spontane Deformation) und der Domaenenbeweglichkeit {eta} zuordnen. Die Modifikation von PZT erfolgt durch Substitution isovalenter oder heterovalenter Ionen unter Beruecksichtigung von Ionenradien und -wertigkeit auf A- und B-Plaetzen des Perowskigitters. Die Substitution bestimmter Ionen ist das Verfahren zur Schaffung neuer piezokeramischer Werkstoffe und wird insbesondere zur Einstellung der Werte einzelner Kenngroessen auf einem bestimmten Niveau entsprechend den technischen Anforderungen angewendet. (orig.)

A concept for the development of piezoceramic materials based on lead zirconate titanate (PZT). Part 1; Ein Entwicklungskonzept piezokeramischer Werkstoffe auf der Basis von Gleizirkonattitanat (PZT). Teil 1

Energy Technology Data Exchange (ETDEWEB)

Helke, G. [CeramTec AG, Lauf a.d. Pegnitz (Germany)

2002-07-01

Piezoceramic ceramics based on Lead Zircontate Titanate (PZT) show - within a relatively close Zr/Ti ratio range (close to the ratio 0.5/0.5) - extreme values for remanent polarization P{sub r} and the dielectric coefficient {epsilon}{sub 33}{sup {tau}}/{epsilon}{sub 0} as well as their corresponding piezoelectric coefficients. Remanent polarization P{sub t} can be directly correlated to the structural parameter {delta} (spontaneous deformation) and the domain mobility {eta}. PZT modification results from the substitution of isovalent or heterovalent ions, thereby taking ion radii and valency at the A and B sites of the perovskite-type lattice under consideration. The substitution of specific ions is the process used to develop new piezoceramic materials which is mainly applied to determine the values of specific parameters corresponding to technical requirements. (orig.) [German] Piezoelektrische Keramiken auf der Basis von Bleizirkonattitanat (PZT) weisen in einem relativ engen Bereich des Zr/Ti-Verhaeltnisses (nahe dem Verhaeltnis 0,5/0,5). Extremwerte der remanenten Polarisation P{sub r} und der Dielektrizitaetskonstanten {epsilon}{sub 33}{sup {tau}}/{epsilon}{sub 0} sowie der von ihnen abhaengigen piezoelektrischen Kenngroessen auf. Die remanente Polarisation P{sub r} laesst sich unmittelbar dem Strukturparameter {delta} (spontane Deformation) und der Domaenenbeweglichkeit {eta} zuordnen. Die Modifikation von PZT erfolgt durch Substitution isovalenter oder heterovalenter Ionen unter Beruecksichtigung von Ionenradien und -wertigkeit auf A- und B-Plaetzen des Perowskigitters. Die Substitution bestimmter Ionen ist das Verfahren zur Schaffung neuer piezokeramischer Werkstoffe und wird insbesondere zur Einstellung der Werte einzelner Kenngroessen auf einem bestimmten Niveau entsprechend den technischen Anforderungen angewendet. (orig.)

Modeling and Positioning of a PZT Precision Drive System

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Che Liu

2017-11-01

Full Text Available The fact that piezoelectric ceramic transducer (PZT precision drive systems in 3D printing are faced with nonlinear problems with respect to positioning, such as hysteresis and creep, has had an extremely negative impact on the precision of laser focusing systems. To eliminate the impact of PZT nonlinearity during precision drive movement, mathematical modeling and theoretical analyses of each module comprising the system were carried out in this study, a micro-displacement measurement circuit based on Position Sensitive Detector (PSD is constructed, followed by the establishment of system closed-loop control and creep control models. An XL-80 laser interferometer (Renishaw, Wotton-under-Edge, UK was used to measure the performance of the precision drive system, showing that system modeling and control algorithms were correct, with the requirements for precision positioning of the drive system satisfied.

Modeling and Positioning of a PZT Precision Drive System.

Science.gov (United States)

Liu, Che; Guo, Yanling

2017-11-08

The fact that piezoelectric ceramic transducer (PZT) precision drive systems in 3D printing are faced with nonlinear problems with respect to positioning, such as hysteresis and creep, has had an extremely negative impact on the precision of laser focusing systems. To eliminate the impact of PZT nonlinearity during precision drive movement, mathematical modeling and theoretical analyses of each module comprising the system were carried out in this study, a micro-displacement measurement circuit based on Position Sensitive Detector (PSD) is constructed, followed by the establishment of system closed-loop control and creep control models. An XL-80 laser interferometer (Renishaw, Wotton-under-Edge, UK) was used to measure the performance of the precision drive system, showing that system modeling and control algorithms were correct, with the requirements for precision positioning of the drive system satisfied.

Effects of electrodes on the properties of sol-gel PZT based capacitors in FeRAM

Science.gov (United States)

Zhang, Ming-Ming; Jia, Ze; Ren, Tian-Ling

2009-05-01

The effects of electrodes on the properties of capacitors applied in ferroelectric random access memories (FeRAM) are investigated in this work. Pt and Ir are used as bottom and top electrodes (BE and TE), respectively, in sol-gel Pb(Zr xTi 1-x)O 3 (PZT) based capacitors. Bottom electrodes are found to play a dominant role in the properties of PZT films and capacitors. Capacitors using Pt as bottom electrode have larger remnant polarization (2Pr) than those using Ir which may result from the different orientations of PZT films. The higher Schottky barrier, more dense film and smaller roughness are believed to be the reasons for the better leakage performance of capacitors using Pt as bottom electrodes. Different vacancies types and interface conditions are believed to be the main reasons for the better fatigue (less than 10% initial 2Pr loss after 10 11 fatigue cycles) and better imprint properties of TE/PZT/Ir capacitors. Top electrodes are found to have smaller impact on the properties of capacitors compared with bottom electrodes. A decrease in 2Pr is found when Ir is used as top electrode instead of Pt for PZT/Pt, which is believed to be caused by the stress resulting from lattice mismatch. The different thermal processes that top and bottom electrodes suffered are believed to be the reason for the different impacts they have on capacitors.

Fabrication and characterization of wide band AE sensors for quantitative detection of displacement and velocity

International Nuclear Information System (INIS)

Kim, Byung G.; Kim, Young Hwan

1992-01-01

Acoustic emission sensors to show a flat response for displacement and velocity of a specimen surface in a wide frequency were fabricated. The sensors were conical sensors employing conical type piezoelectric elements and a PVDF sensor employing PVDF piezoelctric polymer. The transient outputs of the sensors due to step-like forces and their sensitivity spectrum were measured. The results were compared with the theoretical displacement and velocity signals calculated using Green's function and a simulated ramp force. The sensor outputs and the theoretical signals were consistent with each other. The sensors showed flat sensitivity spectra in the wide frequency range. The present work showed that conical PZT sensors are suited for the direct measurement of vertical displacement, and PVDF sensors for that of the vertical velocity of a plate surface.

Micro-fabricated flexible PZT cantilever using d33 mode for energy harvesting

Science.gov (United States)

Cho, Hyunok; Park, Jongcheol; Park, Jae Yeong

2017-12-01

This paper presents a micro-fabricated flexible and curled PZT [Pb(Zr0.52Ti0.48)O3] cantilever using d33 piezoelectric mode for vibration based energy harvesting applications. The proposed cantilever based energy harvester consists of polyimide, PZT thin film, and inter-digitated IrOx electrodes. The flexible cantilever was formed using bulk-micromachining on a silicon wafer to integrate it with ICs. The d33 piezoelectric mode was applied to achieve a large output voltage by using inter-digitated electrodes, and the PZT thin film on polyimide layer has a remnant polarization and coercive filed of approximately 2 P r = 47.9 μC/cm2 and 2 E c = 78.8 kV/cm, respectively. The relative dielectric constant was 900. The fabricated micro-electromechanical systems energy harvester generated output voltages of 1.2 V and output power of 117 nW at its optimal resistive load of 6.6 MΩ from its resonant frequency of 97.8 Hz with an acceleration of 5 m/s2.

Influence of PZT Coating Thickness and Electrical Pole Alignment on Microresonator Properties.

Science.gov (United States)

Janusas, Giedrius; Ponelyte, Sigita; Brunius, Alfredas; Guobiene, Asta; Vilkauskas, Andrius; Palevicius, Arvydas

2016-11-10

With increasing technical requirements in the design of microresonators, the development of new techniques for lightweight, simple, and inexpensive components becomes relevant. Lead zirconate titanate (PZT) is a powerful tool in the formation of these components, allowing a self-actuation or self-sensing capability. Different fabrication methods lead to the variation of the properties of the device itself. This research paper covers the fabrication of a novel PZT film and the investigations of its chemical, surface, and dynamic properties when film thickness is varied. A screen-printing technique was used for the formation of smooth films of 60 µm, 68 µm, and 25 µm thickness. A custom-made poling technique was applied to enhance the piezoelectric properties of the designed films. However, poling did not change any compositional or surface characteristics of the films; changes were only seen in the electrical ones. The results showed that a thinner poled PZT film having a chemical composition with the highest amount of copper and zirconium led to better electrical characteristics (generated voltage of 3.5 mV).

Local Fatigue Evaluation in PZT Thin Films with Nanoparticles by Piezoresponse Force Microscopy

OpenAIRE

B. S. Li

2012-01-01

Lead zirconate titanate (PZT) thin films with the morphotropic phase boundary composition (Zr/Ti = 52/48) have been prepared using a modified diol-based sol-gel route by introducing 1–5 mol% barium titanate (BT) nanoseeds into the precursor solution on platinized silicon substrates (Pt/Ti/SiO2/Si). Macroscopic electric properties of PZT film with nanoparticle showed a significant improvement of ferroelectric properties. This work aims at the systematic study of the local switching polarizatio...

Measurement of the Length of Installed Rock Bolt Based on Stress Wave Reflection by Using a Giant Magnetostrictive (GMS) Actuator and a PZT Sensor.

Science.gov (United States)

Luo, Mingzhang; Li, Weijie; Wang, Bo; Fu, Qingqing; Song, Gangbing

2017-02-23

Rock bolts, as a type of reinforcing element, are widely adopted in underground excavations and civil engineering structures. Given the importance of rock bolts, the research outlined in this paper attempts to develop a portable non-destructive evaluation method for assessing the length of installed rock bolts for inspection purposes. Traditionally, piezoelectric elements or hammer impacts were used to perform non-destructive evaluation of rock bolts. However, such methods suffered from many major issues, such as the weak energy generated and the requirement for permanent installation for piezoelectric elements, and the inconsistency of wave generation for hammer impact. In this paper, we proposed a portable device for the non-destructive evaluation of rock bolt conditions based on a giant magnetostrictive (GMS) actuator. The GMS actuator generates enough energy to ensure multiple reflections of the stress waves along the rock bolt and a lead zirconate titantate (PZT) sensor is used to detect the reflected waves. A new integrated procedure that involves correlation analysis, wavelet denoising, and Hilbert transform was proposed to process the multiple reflection signals to determine the length of an installed rock bolt. The experimental results from a lab test and field tests showed that, by analyzing the instant phase of the periodic reflections of the stress wave generated by the GMS transducer, the length of an embedded rock bolt can be accurately determined.

Non-aqueous electrochemical deposition of lead zirconate titanate films for flexible sensor applications

Science.gov (United States)

Joseph, Sherin; Kumar, A. V. Ramesh; John, Reji

2017-11-01

Lead zirconate titanate (PZT) is one of the most important piezoelectric materials widely used for underwater sensors. However, PZTs are hard and non-compliant and hence there is an overwhelming attention devoted toward making it flexible by preparing films on flexible substrates by different routes. In this work, the electrochemical deposition of composition controlled PZT films over flexible stainless steel (SS) foil substrates using non-aqueous electrolyte dimethyl sulphoxide (DMSO) was carried out. Effects of various key parameters involved in electrochemical deposition process such as current density and time of deposition were studied. It was found that a current density of 25 mA/cm2 for 5 min gave a good film. The morphology and topography evaluation of the films was carried out by scanning electron microscopy (SEM) and atomic force microscopy (AFM), respectively, which showed a uniform morphology with a surface roughness of 2 nm. The PZT phase formation was studied using X-ray diffraction (XRD) and corroborated with Raman spectroscopic studies. The dielectric constant, dielectric loss, hysteresis and I-V characteristics of the film was evaluated.

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

Science.gov (United States)

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-x) wt% Na,Bi,Sr-doped PZT (PZTNB-1)+x wt% Y3Fe5O12 (YIG) with x=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, ΔE/ΔH 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. ΔE/ΔH value of 0-3 composites with x=40-60 wt% was found to be ∼1.6 mV/(cm Oe).

The converse magnetoelectric coupling in asymmetric granule/matrix composite film with Ni/PZT component

Science.gov (United States)

Chen, Bo; Su, Ning-Ning; Cui, Wen-Li; Yan, Shi-Nong

2018-04-01

In this work, a type of asymmetric granule/matrix composite film is designed, where the Ni granule is dispersed in PZT matrix, meanwhile the top and bottom electrode is constituted by Au and SRO respectively. Predicted through the electrostatic screening model and mean field approximation, considerable electrostatic charge is induced on Ni granule surface by ferroelectric PZT polarization. Predicted through the spin splitting model and spherical shell approximation, both the magnetization and magnetic anisotropy of Ni granule are modulated by ferroelectric PZT polarization. As the volume fraction of Ni granule is increased, the electric modulation of magnetization and magnetic anisotropy is reduced and enhanced respectively. As the dimension of granule/matrix composite is varied, such modulation is retained. Due to the large area-volume ratio of nano-granule, this work benefits to realize the converse magnetoelectric coupling in nanoscale.

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

Science.gov (United States)

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.

Broadband Electromagnetic Emission from PZT Ferroelectric Ceramics after Shock Loading

Directory of Open Access Journals (Sweden)

Fiodoras ANISIMOVAS

2013-12-01

Full Text Available It was experimentally registered pulsed electromagnetic (EM radiation in frequency range higher than television one using wideband horns with coaxial and waveguide outputs. The EM radiation was received during shock loading of lead zirconate titanate (PZT ceramics cylinders in conventional piezoelectric ignition mechanisms. Digital oscilloscope allows registering whole series of EM pulses and each pulse from the series transmitted from horn antenna of (1 – 18 GHz operating band frequencies. There is (1 – 4 ms delay between the shock and the first pulse of the series. Duration of the series is about (3 – 4 ms. The PZT cylinders were cleaved along their axes and the surfaces formed in the process were investigated by scanning electron microscope. It was concluded that from electrical point of view PZT ceramics contain interacting subsystems. It was found that EM radiation spectrum of pulse detected by waveguide detector heads has harmonics reaching 80 GHz. Presence of harmonics higher than 20 GHz indicates on radiation due to deceleration of electrons emitted during the switching. The EM pulses in the series appear randomly and have different amplitudes which partly confirmed thesis on independent switching dynamics of small volumes governed by a local electric field.DOI: http://dx.doi.org/10.5755/j01.ms.19.4.3137

Structural Health Monitoring System Trade Space Analysis Tool with Consideration for Crack Growth, Sensor Degradation and a Variable Detection Threshold

Science.gov (United States)

2014-09-18

Fatigue crack growth ..................................................................................................25 Probability of detection...32 Figure 5: Fatigue crack growth simulation results for 10 runs .............................................. 35 Figure 6...43 Figure 10: Linear regression fit of ln() vs. ln( ) data for SHM using PZT sensors (Kuhn, 2009

A Study on Detection of Elastic Wave Using Patch Type Piezo-Polymer Sensor

International Nuclear Information System (INIS)

Kim, Ki Bok; Yoon, Dong Jin; Kueon, Jae Hwa; Lee, Young Seop

2004-01-01

Patch type piezo-polymer sensors for smart structures were experimented to detect elastic wave. The pencil lead braking test was performed to analyze the characteristics of patch-type piezo-polymer sensors such as polyvinyliden fluoride (PVDF) and polyvinylidene fluoride trifluorethylene (P(VDF-TrFE)) for several test specimens with various elastic wave velocities and acoustical impedances. The characteristics of the patch-type piezo-polymer sensor were compared with the commercial PZT acoustic emission (AE) sensor. The vacuum grease and epoxy resin were used as a couplant for the acoustic impedance matching between the sensor and specimen. The peak amplitude of elastic wave increased as the diameter of piezo-film and acoustical impedance of the specimen increased. The frequency detection range of the piezo-film sensors decreased with increasing diameter of the piezo-film sensor. The P(VDF-TrFE) sensor was more sensitive than the PVDF sensor

A Piezoelectric PZT Ceramic Mulitlayer Stack for Energy Harvesting Under Dynamic Forces

Science.gov (United States)

Xu, Tian-Bing; Siochi, Emilie J.; Kang, Jin Ho; Zuo, Lei; Zhou, Wanlu; Tang, Xiudong; Jiang, Xiaoning

2011-01-01

Piezoelectric energy harvesting transducers (PEHTs) are commonly used in motion/vibration energy scavenging devices. To date, most researchers have focused on energy harvesting at narrow bandwidths around the mechanical resonance frequency, and most piezoelectric harvesting devices reported in the literature have very low effective piezoelectric coefficient (d(sub eff)) (coefficients of about 100 pC/N. The level of harvested electrical power for CBPEHTs is on the order of microW even at resonance mode. In order to harvest more electrical energy across broader bandwidth, high effective piezoelectric coefficient structures are needed. In this study, we investigate a "33" longitudinal mode, piezoelectric PZT ceramic multilayer stack (PZT-Stack) with high effective piezoelectric coefficient for high-performance PEHTs. The PZT-Stack is composed of 300 layers of 0.1 mm thick PZT plates, with overall dimensions of 32.4 mm X 7.0 mm X 7.0 mm. Experiments were carried out with dynamic forces in a broad bandwidth ranging from 0.5 Hz to 25 kHz. The measured results show that the effective piezoelectric coefficient of the PZT-stack is about 1 X 10(exp 5) pC/N at off-resonance frequencies and 1.39 X 10(exp 6) pC/N at resonance, which is order of magnitude larger than that of traditional PEHTs. The effective piezoelectric coefficients (d(sub eff)) do not change significantly with applied dynamic forces having root mean square (RMS) values ranging from 1 N to 40 N. In resonance mode, 231 mW of electrical power was harvested at 2479 Hz with a dynamic force of 11.6 N(sub rms), and 7.6 mW of electrical power was generated at a frequency of 2114 Hz with 1 N(sub rms) dynamic force. In off-resonance mode, an electrical power of 18.7 mW was obtained at 680 Hz with a 40 N(sub rms) dynamic force. A theoretical model of energy harvesting for the PZT-Stack is established. The modeled results matched well with experimental measurements. This study demonstrated that high effective

Sputter deposition of PZT piezoelectric films on thin glass substrates for adjustable x-ray optics.

Science.gov (United States)

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

2013-05-10

Piezoelectric PbZr(0.52)Ti(0.48)O(3) (PZT) thin films deposited on thin glass substrates have been proposed for adjustable optics in future x-ray telescopes. The light weight of these x-ray optics enables large collecting areas, while the capability to correct mirror figure errors with the PZT thin film will allow much higher imaging resolution than possible with conventional lightweight optics. However, the low strain temperature and flexible nature of the thin glass complicate the use of chemical-solution deposition due to warping of the substrate at typical crystallization temperatures for the PZT. RF magnetron sputtering enabled preparation of PZT films with thicknesses up to 3 μm on Schott D263 glass substrates with much less deformation. X-ray diffraction analysis indicated that the films crystallized with the perovskite phase and showed no indication of secondary phases. Films with 1 cm(2) electrodes exhibited relative permittivity values near 1100 and loss tangents below 0.05. In addition, the remanent polarization was 26 μC/cm(2) with coercive fields of 33 kV/cm. The transverse piezoelectric coefficient was as high as -6.1±0.6 C/m(2). To assess influence functions for the x-ray optics application, the piezoelectrically induced deflection of individual cells was measured and compared with finite-element-analysis calculations. The good agreement between the results suggests that actuation of PZT thin films can control mirror figure errors to a precision of about 5 nm, allowing sub-arcsecond imaging.

Finite Element Analysis of Single Cell Stiffness Measurements Using PZT-Integrated Buckling Nanoneedles

Directory of Open Access Journals (Sweden)

Maryam Alsadat Rad

2016-12-01

Full Text Available This paper proposes a new technique for real-time single cell stiffness measurement using lead zirconate titanate (PZT-integrated buckling nanoneedles. The PZT and the buckling part of the nanoneedle have been modelled and validated using the ABAQUS software. The two parts are integrated together to function as a single unit. After calibration, the stiffness, Young’s modulus, Poisson’s ratio and sensitivity of the PZT-integrated buckling nanoneedle have been determined to be 0.7100 N·m−1, 123.4700 GPa, 0.3000 and 0.0693 V·m·N−1, respectively. Three Saccharomyces cerevisiae cells have been modelled and validated based on compression tests. The average global stiffness and Young’s modulus of the cells are determined to be 10.8867 ± 0.0094 N·m−1 and 110.7033 ± 0.0081 MPa, respectively. The nanoneedle and the cell have been assembled to measure the local stiffness of the single Saccharomyces cerevisiae cells The local stiffness, Young’s modulus and PZT output voltage of the three different size Saccharomyces cerevisiae have been determined at different environmental conditions. We investigated that, at low temperature the stiffness value is low to adapt to the change in the environmental condition. As a result, Saccharomyces cerevisiae becomes vulnerable to viral and bacterial attacks. Therefore, the proposed technique will serve as a quick and accurate process to diagnose diseases at early stage in a cell for effective treatment.

Finite Element Analysis of Single Cell Stiffness Measurements Using PZT-Integrated Buckling Nanoneedles.

Science.gov (United States)

Rad, Maryam Alsadat; Tijjani, Auwal Shehu; Ahmad, Mohd Ridzuan; Auwal, Shehu Muhammad

2016-12-23

This paper proposes a new technique for real-time single cell stiffness measurement using lead zirconate titanate (PZT)-integrated buckling nanoneedles. The PZT and the buckling part of the nanoneedle have been modelled and validated using the ABAQUS software. The two parts are integrated together to function as a single unit. After calibration, the stiffness, Young's modulus, Poisson's ratio and sensitivity of the PZT-integrated buckling nanoneedle have been determined to be 0.7100 N·m -1 , 123.4700 GPa, 0.3000 and 0.0693 V·m·N -1 , respectively. Three Saccharomyces cerevisiae cells have been modelled and validated based on compression tests. The average global stiffness and Young's modulus of the cells are determined to be 10.8867 ± 0.0094 N·m -1 and 110.7033 ± 0.0081 MPa, respectively. The nanoneedle and the cell have been assembled to measure the local stiffness of the single Saccharomyces cerevisiae cells The local stiffness, Young's modulus and PZT output voltage of the three different size Saccharomyces cerevisiae have been determined at different environmental conditions. We investigated that, at low temperature the stiffness value is low to adapt to the change in the environmental condition. As a result, Saccharomyces cerevisiae becomes vulnerable to viral and bacterial attacks. Therefore, the proposed technique will serve as a quick and accurate process to diagnose diseases at early stage in a cell for effective treatment.

Synthesis and mechanical characterization of PZT/Sr based composite ceramics with addition of Si{sub 3}N{sub 4}; Sintese e caracterizacao mecanica de ceramicas compositas a base de PZT/Sr com adicoes de Si{sub 3}N{sub 4}

Energy Technology Data Exchange (ETDEWEB)

Santos, M.A.P.; Santos, R.C.P.; Santos, M.C.C.; Rocha, C.D.G.; Silva, M., E-mail: cida@ipqm.mar.mil.b [Instituto de Pesquisas da Marinha (IPqM), Ilha do Governador, RJ (Brazil). Grupo de Materiais

2010-07-01

In the Underwater Acoustics field, piezoelectric ceramics are the most usually employed materials for the conversion of mechanical energy (acoustic signal) into electric energy (electric signal) and vice-versa, in sensors (hydrophones) or hydroacoustic projectors. In the development of new compositions for these applications, piezoelectric performance is generally prioritized, to the expense of its mechanical properties. With this in mind, the object of this work was to study the effects of the addition of Si{sub 3}N{sub 4} in the mechanical properties of PZT-Sr based electronic ceramics. Thus, a novel piezoelectric ceramic with the addition of small percentages in weight (0;0.1;1;3 and 5) of the structural ceramic Si{sub 3}N{sub 4} was successfully processed by the oxide mixing route ; the compounds were sintered in a conventional at 1200 deg C for 2h. The densities of the compounds thus obtained for the different percentages of Si{sub 3}N{sub 4} ranged from 55 to 97% and decreased with the increase of the content of Si{sub 3}N{sub 4}. Presence of equiaxial grains with normal growth was observed in all samples. MEV/EDS analysis of the micro-structures of the compositions detected the presence of a second phase rich in Zr, confirmed by DRX, which is a result of large quantities of volatilized PbO; the sintered pieces had their mechanical properties investigated by ultra-sonic inspection. It was observed that, among the sintered compositions, the PZT-Sr ceramic with 0.1% Si{sub 3}N{sub 4} presented the smallest value for Young's Modulus E and Shear Modulus G, 75 Gpa and 28 Gpa, respectively. The Poisson's Coefficients {nu} tended to decrease with the increase of Si{sub 3}N{sub 4} added to the PZT-Sr ceramic, indicating, thus, that the added compound may be used to adjust the mechanical properties of the material. (author)

Ellipsometry non-destructive technique for PZT thin films investigations

Czech Academy of Sciences Publication Activity Database

Deineka, Alexander; Jastrabík, Lubomír; Soukup, Ladislav

11-12, - (2000), s. 329-331 ISSN 0447-6441 R&D Projects: GA MŠk LN00A015 Institutional research plan: CEZ:AV0Z1010914 Keywords : PZT * J.A. Wollam spectral ellipsometer * refractive index depth profiels Subject RIV: BM - Solid Matter Physics ; Magnetism

Elasticity Imaging of Ferroelectric Domain Structure in PZT by Ultrasonic Atomic Force Microscopy

International Nuclear Information System (INIS)

Tsuji, T.; Ogiso, H.; Fukuda, K.; Yamanaka, K.

2004-01-01

UAFM was applied to the observation of the domain structure in lead zirconate titanate (PZT). It imaged the change of elasticity due to grain and domain boundary (DB). For the quantitative evaluation of the contact stiffness, the lateral contact stiffness was taken into account. The stiffness of DB was 10% lower than that within the domain and the width of the DB was about 30 nm. The implication of this work is the understanding of the fatigue mechanism in a PZT memory and the high resolution imaging for a high-density memory

Influences of PZT addition on phase formation and magnetic properties of perovskite Pb(Fe{sub 0.5}Nb{sub 0.5})O{sub 3}-based ceramics

Energy Technology Data Exchange (ETDEWEB)

Amonpattaratkit, P. [Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Jantaratana, P. [Department of Physics, Faculty of Science, Kasetsart University, Bangkok 10900 (Thailand); Ananta, S., E-mail: suponananta@yahoo.com [Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand)

2015-09-01

In this work, the investigation of phase formation, crystal structure, microstructure, microchemical composition and magnetic properties of perovskite (1−x)PFN–xPZT (x=0.1–0.5) multiferroic ceramics derived from a combination of perovskite stabilizer PZT and a wolframite-type FeNbO{sub 4}B-site precursor was carried out by using a combination of X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) analyzer and vibrating sample magnetometer (VSM) techniques. The addition of PZT phase and its concentration have been found to have pronounced effects on the perovskite phase formation, densification, grain growth and magnetic properties of the sintered ceramics. XRD spectra from these ceramics reveal transformation of the (pseudo) cubic into the tetragonal perovskite structure. When increasing PZT content, the degree of perovskite phase formation and the tetragonality value of the ceramics increase gradually accompanied with the variation of cell volume, the M–H hysteresis loops, however, become narrower accompanied by the decrease of maximum magnetization (M{sub max}), remanent polarization (M{sub r}), and coercive field (H{sub C}). - Highlights: • Fabrication of PFN-PZT multiferroic ceramics from PZT and FeNbO{sub 4} precursors. • Effect of PZT content on phase transformation of PFN-PZT multiferroic ceramics. • Effect of PZT content on magnetic properties of PFN-PZT multiferroic ceramics.

Health Monitoring of a Composite Actuator with a PZT Ceramic during Electromechanical Fatigue Loading

International Nuclear Information System (INIS)

Woo, Sung Choong; Goo, Nam Seo

2007-01-01

This work describes an investigation into the feasibility of using an acoustic emission (AE) technique to evaluate the integrity of a composite actuator with a PZT ceramic under electromechanical cyclic loading. AE characteristics have been analyzed in terms of the behavior of the AE count rate and signal waveform in association with the performance degradation of the composite actuator during the cyclic tests. The results showed that the fatigue cracking of the composite actuator with a PZT ceramic occurred only in the PZT ceramic layer, and that the performance degradation caused by the fatigue damage varied immensely depending on the existence of a protecting composite bottom layer. We confirmed the correlations between the fatigue damage mechanisms and AE signal types for the actuators that exhibited multiple modes of fatigue damage; transgranular micro damage, intergranular fatigue cracking, and breakdown by a short circuiting were related to a burst type signal showing a shortly rising and slowly decaying waveform with a comparably low voltage, a continuous type signal showing a gradual rising and slowly decaying waveform with a very high voltage and a burst and continuous type signal with a high voltage, respectively. Results from the present work showed that the evolution of fatigue damage in the composite actuator with a PZT ceramic can be nondestructively identified via in situ AE monitoring and microscopic observations

Hydrothermally synthesized PZT film grown in highly concentrated KOH solution with large electromechanical coupling coefficient for resonator

Science.gov (United States)

Feng, Guo-Hua; Lee, Kuan-Yi

2017-12-01

This paper presents a study of lead zirconate titanate (PZT) films hydrothermally grown on a dome-shaped titanium diaphragm. Few articles in the literature address the implementation of hydrothermal PZT films on curved-diaphragm substrates for resonators. In this study, a 50-μm-thick titanium sheet is embossed using balls of designed dimensions to shape a dome-shaped cavity array. Through single-process hydrothermal synthesis, PZT films are grown on both sides of the processed titanium diaphragm with good adhesion and uniformity. The hydrothermal synthesis process involves a high concentration of potassium hydroxide solution and excess amounts of lead acetate and zirconium oxychloride octahydrate. Varied deposition times and temperatures of PZT films are investigated. The grown films are characterized by X-ray diffraction and scanning electron microscopy. The 10-μm-thick PZT dome-shaped resonators with 60- and 20-μm-thick supporting layers are implemented and further tested. Results for both resonators indicate that large electromechanical coupling coefficients and a series resonance of 95 MHz from 14 MHz can be attained. The device is connected to a complementary metal-oxide-semiconductor integrated circuit for analysis of oscillator applications. The oscillator reaches a Q value of 6300 in air. The resonator exhibits a better sensing stability when loaded with water when compared with air.

Real-Time Performance of Mechatronic PZT Module Using Active Vibration Feedback Control.

Science.gov (United States)

Aggogeri, Francesco; Borboni, Alberto; Merlo, Angelo; Pellegrini, Nicola; Ricatto, Raffaele

2016-09-25

This paper proposes an innovative mechatronic piezo-actuated module to control vibrations in modern machine tools. Vibrations represent one of the main issues that seriously compromise the quality of the workpiece. The active vibration control (AVC) device is composed of a host part integrated with sensors and actuators synchronized by a regulator; it is able to make a self-assessment and adjust to alterations in the environment. In particular, an innovative smart actuator has been designed and developed to satisfy machining requirements during active vibration control. This study presents the mechatronic model based on the kinematic and dynamic analysis of the AVC device. To ensure a real time performance, a H2-LQG controller has been developed and validated by simulations involving a machine tool, PZT actuator and controller models. The Hardware in the Loop (HIL) architecture is adopted to control and attenuate the vibrations. A set of experimental tests has been performed to validate the AVC module on a commercial machine tool. The feasibility of the real time vibration damping is demonstrated and the simulation accuracy is evaluated.

Effect of porosity on dielectric properties and microstructure of porous PZT ceramics

Energy Technology Data Exchange (ETDEWEB)

Kumar, B. Praveen [PZT Centre, Armament Research and Development Establishment, Pune 411021 (India); Kumar, H.H. [PZT Centre, Armament Research and Development Establishment, Pune 411021 (India); Kharat, D.K. [PZT Centre, Armament Research and Development Establishment, Pune 411021 (India)]. E-mail: dkkharat@rediffmail.com

2006-02-25

Porous piezoelectric materials are of great interest because of their high hydrostatic figure of merit and low sound velocity, which results in to low acoustic impedance and efficient coupling with medium. Porous lead zirconate titanate (PZT) ceramics with varying porosity was developed using polymethyl methacrylate by burnable plastic spheres (BURPS) process. The porous PZT ceramics were characterized for dielectric constant ({epsilon}), dielectric loss factor (tan {delta}), hydrostatic charge (d {sub h}) and voltage (g {sub h}) coefficients and microstructure. The effect of the porous microstructure on the dielectric constant and loss factor at frequencies of 10-10{sup 5} Hz are discussed in this paper.

Microwave hydrothermal synthesis and characterization of PZT 52/48 powders

International Nuclear Information System (INIS)

Teixeira, G.F.; Gasparotto, G.; Santos, N.A.; Zaghete, M.A.; Varela, J.A.; Longo, E.

2009-01-01

Full text: Lead Zirconate Titanate (PZT) is a ceramic witch has great interest because of their ferroelectric, piezoelectric, and other electrical properties. In this work Pb(ZrxTi1-x)O3 powders were synthesized by microwave hydrothermal synthesis (M-H) at 180°C without excess lead content. This method allows obtaining particles whit nanometer size, good stoichiometric controls, high purity and crystalline degree at low temperatures and short times of synthesis. Powders were synthesized with molar concentration of 0.15 mol.L -1 during different times: 30 min, 2, 4, 6 and 8 h. After that the powders were characterized by X-ray diffraction (XRD), Field Emission Gun (FEG) and photoluminescence (PL). Through analysis it is observed that the crystalline phase of PZT is obtained from 2 hours of synthesis and this same time also presents more intense PL emission. (author)

Far infrared and Raman response in tetragonal PZT ceramic films

Energy Technology Data Exchange (ETDEWEB)

Buixaderas, E.; Kadlec, C.; Vanek, P.; Drnovsek, S.; Ursic, H.; Malic, B.

2015-07-01

PbZr{sub 0}.38Ti{sub 0}.62O{sub 3} and PbZr{sub 0}.36Ti{sub 0}.64{sub O}3 thick films deposited by screen printing on (0 0 0 1) single crystal sapphire substrates and prepared at two different sintering temperatures, were studied by Fourier-transform infrared reflectivity, time-domain TH{sub z} transmission spectroscopy and micro-Raman spectroscopy. The dielectric response is discussed using the Lichtenecker model to account for the porosity of the films and to obtain the dense bulk dielectric functions. Results are compared with bulk tetragonal PZT 42/58 ceramics. The dynamic response in the films is dominated by an overdamped lead-based vibration in the TH{sub z} range, as known in PZT, but its evaluated dielectric contribution is affected by the porosity and roughness of the surface. (Author)

Electrodynamic properties of porous PZT-Pt films at terahertz frequency range

Energy Technology Data Exchange (ETDEWEB)

Komandin, Gennady A.; Porodinkov, Oleg E.; Spektor, Igor E.; Volkov, Alexander A. [Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); Vorotilov, Konstantin A.; Seregin, Dmitry S.; Sigov, Alexander S. [Moscow Technological University (MIREA), Moscow (Russian Federation)

2017-01-15

Electrodynamics of Si-SiO{sub 2}-TiO{sub 2}-Pt-PZT heterostructures is studied in the frequency range from 5 to 5000 cm{sup -1} by monochromatic BWO (backward wave oscillator) and infrared Fourier-transform spectroscopy techniques to derive the dielectric characteristics of the sol-gel porous ferroelectric PbZr{sub 0.48}Ti{sub 0.52}O{sub 3} films. Broad frequency band dielectric response of PZT films with different density is constructed using the oscillator dispersion models. The main contribution to the film permittivity is found to form at frequencies below 100 cm{sup -1} depending strongly and non-linearly on the film medium density. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Dielectric characteristics of PZT 95/5 ferroelectric ceramics at high pressures

International Nuclear Information System (INIS)

Spears, R.K.

1978-01-01

The room temperature dielectric properties of a ferroelectric ceramic having a nominal composition of 95 atomic percent lead zirconate and 5 atomic percent lead titanate (designated as PZT 95/5) with a niobium dopant were examined at high hydrostatic pressures using a tetrahedral anvil apparatus. This ceramic has practical applications as a power source in which large quantities of charge are released by dynamic (shock wave) depolarization. Numerous mathematical models of this process have been proposed; however, the use of models has been limited because of the lack of high pressure electrical properties. This study attempted to provide these data on PZT 95/5 by determining the small signal and high electric field dielectric properties at pressures over 4 GPa

Enhanced voltage-controlled magnetic anisotropy in magnetic tunnel junctions with an MgO/PZT/MgO tunnel barrier

Science.gov (United States)

Chien, Diana; Li, Xiang; Wong, Kin; Zurbuchen, Mark A.; Robbennolt, Shauna; Yu, Guoqiang; Tolbert, Sarah; Kioussis, Nicholas; Khalili Amiri, Pedram; Wang, Kang L.; Chang, Jane P.

2016-03-01

Compared with current-controlled magnetization switching in a perpendicular magnetic tunnel junction (MTJ), electric field- or voltage-induced magnetization switching reduces the writing energy of the memory cell, which also results in increased memory density. In this work, an ultra-thin PZT film with high dielectric constant was integrated into the tunneling oxide layer to enhance the voltage-controlled magnetic anisotropy (VCMA) effect. The growth of MTJ stacks with an MgO/PZT/MgO tunnel barrier was performed using a combination of sputtering and atomic layer deposition techniques. The fabricated MTJs with the MgO/PZT/MgO barrier demonstrate a VCMA coefficient, which is ˜40% higher (19.8 ± 1.3 fJ/V m) than the control sample MTJs with an MgO barrier (14.3 ± 2.7 fJ/V m). The MTJs with the MgO/PZT/MgO barrier also possess a sizeable tunneling magnetoresistance (TMR) of more than 50% at room temperature, comparable to the control MTJs with an MgO barrier. The TMR and enhanced VCMA effect demonstrated simultaneously in this work make the MgO/PZT/MgO barrier-based MTJs potential candidates for future voltage-controlled, ultralow-power, and high-density magnetic random access memory devices.

Highly polarized single-c-domain single-crystal Pb(Mn,Nb)O(3)-PZT thin films.

Science.gov (United States)

Wasa, Kiyotaka; Adachi, Hideaki; Nishida, Ken; Yamamoto, Takashi; Matsushima, Tomoaki; Kanno, Isaku; Kotera, Hidetoshi

2012-01-01

In-plane unstrained single-c-domain/single-crystal thin films of PZT-based ternary ferroelectric perovskite, ξPb(Mn,Nb)O3-(1 - ξ)PZT, were grown on SrRuO(3)/Pt/MgO substrates using magnetron sputtering followed by quenching. The sputtered unstrained thin films exhibit unique ferroelectric properties: high coercive field, Ec > 180 kV/cm, large remanent polarization, P(r) = 100 μC/cm(2), small relative dielectric constants, ε* = 100 to 150, high Curie temperature, Tc = ~600 °C, and bulk-like large transverse piezoelectric constants, e31,f = -12.0 C/m(2) for PZT(48/52) at ξ = 0.06. The unstrained thin films are an ideal structure to extract the bulk ferroelectric properties. Their micro-structures and ferroelectric properties are discussed in relation to the potential applications for piezoelectric MEMS. © 2012 IEEE

Study on optimizing ultrasonic irradiation period for thick polycrystalline PZT film by hydrothermal method.

Science.gov (United States)

Ohta, Kanako; Isobe, Gaku; Bornmann, Peter; Hemsel, Tobias; Morita, Takeshi

2013-04-01

The hydrothermal method utilizes a solution-based chemical reaction to synthesize piezoelectric thin films and powders. This method has a number of advantages, such as low-temperature synthesis, and high purity and high quality of the product. In order to promote hydrothermal reactions, we developed an ultrasonic assisted hydrothermal method and confirmed that it produces dense and thick lead-zirconate-titanate (PZT) films. In the hydrothermal method, a crystal growth process follows the nucleation process. In this study, we verified that ultrasonic irradiation is effective for the nucleation process, and there is an optimum irradiation period to obtain thicker PZT films. With this optimization, a 9.2-μm-thick PZT polycrystalline film was obtained in a single deposition process. For this film, ultrasonic irradiation was carried out from the beginning of the reaction for 18 h, followed by a 6 h deposition without ultrasonic irradiation. These results indicate that the ultrasonic irradiation mainly promotes the nucleation process. Copyright © 2012 Elsevier B.V. All rights reserved.

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

Science.gov (United States)

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.

New fabrication of high-frequency (100-MHz) ultrasound PZT film kerfless linear array.

Science.gov (United States)

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

2013-04-01

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.

Triaxial MEMS accelerometer with screen printed PZT thick film

DEFF Research Database (Denmark)

Hindrichsen, Christian Carstensen; Almind, Ninia Sejersen; Brodersen, Simon Hedegaard

2010-01-01

. In this work integration of a screen printed piezoelectric PZT thick film with silicon MEMS technology is shown. A high bandwidth triaxial accelerometer has been designed, fabricated and characterized. The voltage sensitivity is 0.31 mV/g in the vertical direction, 0.062 mV/g in the horizontal direction...

Phase transitions in PZT ceramics prepared by different techniques

Czech Academy of Sciences Publication Activity Database

Deineka, Alexander; Suchaneck, G.; Jastrabík, Lubomír; Gerlach, G.

2002-01-01

Roč. 41, 11B (2002), s. 6966-6968 ISSN 0021-4922 R&D Projects: GA MŠk LN00A015 Institutional research plan: CEZ:AV0Z1010914 Keywords : PZT * phase transitions * band gap * ferroelectrics Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.280, year: 2002

Ferroelectric switching of band alignments in LSMO/PZT/Co multiferroic tunnel junctions: an ab initio study.

Science.gov (United States)

Imam, M; Stojić, N; Binggeli, N

2017-08-04

Band alignments in ferroelectric tunnel junctions (FTJs) are expected to play a critical role in determining the charge transport across the tunneling barrier. In general, however, the interface band discontinuities and their polarization dependence are not well known in these systems. Using a first-principles density-functional-theory approach, we explore the ferroelectric (FE) polarization dependence of the band alignments in [Formula: see text] (LSMO/PZT/Co) multiferroic tunnel junctions, for which recent experiments indicated an ON/OFF conductivity behavior upon switching the PZT FE polarization. Our results on the pseudomorphic defect-free LSMO/PZT/Co FTJs evidence a major FE switching effect on the band discontinuities at both interfaces. Based on the changes in the band alignments, we provide a possible explanation for the observed trends in the resistive switching.

Piezoelectric Resonance Investigation of Zr-rich PZT at Room Temperature

NARCIS (Netherlands)

Cereceda, N.; Noheda, B.; Fernandez-del-Castillo, J.R.; Gonzalo, J.A.; Frutos, J. De

1999-01-01

We study the piezoelectric resonances in poled PZT ceramics by means of a microscopic model. It connects the microscopic vibrations of the ionic units, cooperatively producing the piezoelectric effect, with the macroscopic piezoelectric parameters. The behaviour at the resonance is well described in

Presentation and characterization of novel thick-film PZT microactuators

Energy Technology Data Exchange (ETDEWEB)

Chalvet, Vincent; Habineza, Didace, E-mail: didace.habineza@femto-st.fr; Rakotondrabe, Micky; Clévy, Cédric

2016-04-01

We propose in this paper the characterization of a new generation of piezoelectric cantilevers called thick-films piezoelectric actuators. Based on the bonding and thinning process of a bulk PZT layer onto a silicon layer, these cantilevers can provide better static and dynamic performances compared to traditional piezocantilevers, additionally to the small dimensions.

Thin PZT-Based Ferroelectric Capacitors on Flexible Silicon for Nonvolatile Memory Applications

KAUST Repository

Ghoneim, Mohamed T.

2015-04-24

A flexible version of traditional thin lead zirconium titanate ((Pb1.1Zr0.48Ti0.52O3)-(PZT)) based ferroelectric random access memory (FeRAM) on silicon shows record performance in flexible arena. The thin PZT layer requires lower operational voltages to achieve coercive electric fields, reduces the sol-gel coating cycles required (i.e., more cost-effective), and, fabrication wise, is more suitable for further scaling of lateral dimensions to the nano-scale due to the larger feature size-to-depth aspect ratio (critical for ultra-high density non-volatile memory applications). Utilizing the inverse proportionality between substrate\\'s thickness and its flexibility, traditional PZT based FeRAM on silicon is transformed through a transfer-less manufacturable process into a flexible form that matches organic electronics\\' flexibility while preserving the superior performance of silicon CMOS electronics. Each memory cell in a FeRAM array consists of two main elements; a select/access transistor, and a storage ferroelectric capacitor. Flexible transistors on silicon have already been reported. In this work, we focus on the storage ferroelectric capacitors, and report, for the first time, its performance after transformation into a flexible version, and assess its key memory parameters while bent at 0.5 cm minimum bending radius.

Comparison of PZT and FBG sensing technologies for debonding detection on reinforced concrete beams strengthened with external CFRP strips subjected to bending loads

Directory of Open Access Journals (Sweden)

Sevillano, E.

2016-06-01

Full Text Available The development of monitoring technologies particularly suitable to be used with novel CFRP strengthening techniques has gained great attention in recent years. However, in spite of the high performance of these advanced composite materials in the strengthening and repairing of structures in service, they are usually associated with brittle and sudden failure mainly caused by debonding phenomena, originated either at the CFRP-plate end or at the intermediate areas in the vicinity of flexural cracks in the RC beam. Thus, it is highly recommended for these structures to be monitored in order to ensure their integrity while in service. Specifically, the feasibility of smart sensing technologies such as Fiber Bragg Grating (FBG sensors and piezo-impedance transducers (PZT has been studied. To the knowledge of the authors, none serious study has been carried out until now concerned to the topic of damage detection due to debonding in rehabilitated structures with CFRP composites.El desarrollo de tecnologías de monitorización aplicables junto con las novedosas técnicas de refuerzo basadas en materiales CFRP ha recibido una atención creciente los últimos años. Sin embargo, a pesar del alto rendimiento de estos avanzados materiales compuestos en la reparación y refuerzo de estructuras en servicio, están habitualmente asociados a fallos frágiles y repentinos causados principalmente por fenómenos de despegue, originados bien en los extremos del refuerzo, bien en áreas intermedias en las proximidades de grietas de flexión existentes en la viga. Por tanto, es altamente recomendable monitorizar estas soluciones estructurales de cara a garantizar su integridad en servicio. Específicamente, se ha estudiado la viabilidad de sensores inteligentes tales como los sensores Fiber Bragg Grating (FBG o los transductores piezoeléctricos (PZT. Hasta donde los autores saben, no se han realizado estudios serios hasta la fecha abordando la detección de da

Q-factor control of multilayer micromembrane using PZT composite material

Science.gov (United States)

Čekas, Elingas; Janušas, Giedrius; Palevicius, Arvydas; Janušas, Tomas; Ciganas, Justas

2018-02-01

Cantilever and membrane based sensors, which are capable of providing accurate detection of target analytes have been always an important research topic of medical diagnostics, food testing, and environmental monitoring fields. Here, the mechanical detection is achieved by micro- and nano-scale cantilevers for stress sensing and mass sensing, or micro- and nano-scale plates or membranes. High sensitivity is a major issue for the active element and it could be achieved via increased Q-factor. The ability to control the Q factor expands the range of application of the device and allows to achieve more accurate results. The aim of this paper is to investigate the mechanical and electrical properties, as well as, the ability to control the Q factor of the membrane with PZT nanocomposite. This multilayered membrane was formatted using the n-type silicon substrate by implementing the Low Pressure Chemical Vapor Deposition (LPCVD), photolithography by using photomask with defined dimensions, deep etching, and e-beam evaporation techniques. Dynamic and electrical characteristics of the membrane were numerically investigated using COMSOL Multiphysics software. The use of the multilayered membrane can range from simple monitoring of particles concentration in a closed environment to inspecting glucose levels in human fluids (blood, tears, sweat, etc.).

Bulk dielectric and magnetic properties of PFW-PZT ceramics: absence of magnetically switched-off polarization.

Science.gov (United States)

Kempa, M; Kamba, S; Savinov, M; Maryško, M; Frait, Z; Vaněk, P; Tomczyk, M; Vilarinho, P M

2010-11-10

We investigated ceramics samples of solid solutions of [PbFe(2/3)W(1/3)O(3)](x)-[PbZr(0.53)Ti(0.47)O(3)](1 - x) (PFW(x)-PZT(1 - x), x = 0.2 and 0.3) by means of broad-band dielectric spectroscopy, differential scanning calorimetry and SQUID magnetometry. We did not confirm the observations of Kumar et al (2009 J. Phys.: Condens. Matter 21 382204), who reported on reversible suppression of ferroelectric polarization in polycrystalline PFW(x)-PZT(1 - x) thin films for magnetic fields above 0.5 T. We did not observe any change of ferroelectric polarization with external magnetic fields up to 3.2 T. Pirc et al (2009 Phys. Rev. B 79 214114) developed a theory explaining the reported large magnetoelectric effect in PFW(x)-PZT(1 - x), taking into account relaxor magnetic and relaxor ferroelectric properties of the system. Our data revealed classical ferroelectric properties below 525 K and 485 K in samples with x = 0.2 and 0.3, respectively. Moreover, paramagnetic behavior was observed down to 4.5 K instead of previously reported relaxor magnetic behavior. It seems that the reported switching-off of ferroelectric polarization in PFW(x)-PZT(1 - x) thin films is not an intrinsic property, but probably an effect of electrodes, interlayers, grain boundaries or second phases presented in polycrystalline thin films.

PZ, PT and PZT formation from metal citrates

International Nuclear Information System (INIS)

Bastos, C.M.R.; Zaghette, M.A.; Jafelicci Junior, M.; Varela, J.A.

1990-01-01

Lead zirconate, lead titanate and lead titanate-zirconate were obtained by mechanical mixing of lead, titanium and zirconium citrates in ether and by calcination. The process was analyzed by DTA, TGA, IR, pore size distribution and surface area measurements. The results indicate that the decomposition reaction and formation of PZ, PT occur simultaneaously without formation of intermediate compounds. PZT was formed from 500 0 C. (author) [pt

Catching the intermediate phase in PZT 99/1 single crystals

Czech Academy of Sciences Publication Activity Database

Buixaderas, Elena; Ostapchuk, Tetyana; Kroupa, Jan; Savinov, Maxim; Gregora, Ivan; Hlinka, Jiří

2014-01-01

Roč. 87, 10-11 (2014), s. 1105-1113 ISSN 0141-1594 R&D Projects: GA ČR GA13-15110S Institutional support: RVO:68378271 Keywords : Raman spectroscopy * phonons * PZT * antiferroelectrics Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.954, year: 2014

Ionic and electronic conductivity in lead-zirconate-titanate (PZT)

NARCIS (Netherlands)

Boukamp, Bernard A.; Pham thi ngoc mai, P.T.N.M.; Blank, David H.A.; Bouwmeester, Henricus J.M.

2004-01-01

Accurate impedance measurements on differently sized samples of lead–zirconate–titanate (PbZr0.53Ti0.47O3, PZT) have been analyzed with a CNLS procedure, resulting in the separation of the ionic and electronic conductivities over a temperature range from f150 to 630 jC. At 603 jC the electronic

Reconstruction of the domain orientation distribution function of polycrystalline PZT ceramics using vector piezoresponse force microscopy.

Science.gov (United States)

Kratzer, Markus; Lasnik, Michael; Röhrig, Sören; Teichert, Christian; Deluca, Marco

2018-01-11

Lead zirconate titanate (PZT) is one of the prominent materials used in polycrystalline piezoelectric devices. Since the ferroelectric domain orientation is the most important parameter affecting the electromechanical performance, analyzing the domain orientation distribution is of great importance for the development and understanding of improved piezoceramic devices. Here, vector piezoresponse force microscopy (vector-PFM) has been applied in order to reconstruct the ferroelectric domain orientation distribution function of polished sections of device-ready polycrystalline lead zirconate titanate (PZT) material. A measurement procedure and a computer program based on the software Mathematica have been developed to automatically evaluate the vector-PFM data for reconstructing the domain orientation function. The method is tested on differently in-plane and out-of-plane poled PZT samples, and the results reveal the expected domain patterns and allow determination of the polarization orientation distribution function at high accuracy.

Study of the microstructure and the hardness of PZT piezoelectric ceramics types I and III used in electro acoustic transducers; Estudo da microestrutura e da microdureza das ceramicas piezoeletricas tipos PZT I e III utilizadas em transdutores eletroacusticos

Energy Technology Data Exchange (ETDEWEB)

Cabral, Ricardo de Freitas; Itaboray, Lucas Mendes; Santos, Anna Paula de Oliveira [Centro Universitario de Volta Redonda (UNIFOA), Volta Redonda, RJ (Brazil)

2015-12-15

The field of electronic processing of the ceramic piezoelectric type imported powdered led to the production of ceramics with 97% of theoretical density, homogeneous microstructure with great potential for applications in piezoelectric devices such as electro acoustic transducers. However, the production of electronic ceramics National piezoelectric type is not yet able to have as raw material zirconate titanate Lead (PZT) 100% made in Brazil. Thus, this is used for supply of domestic production, the zirconium oxide. In this work, both post PZT types I and III, imported, were uniaxially pressed at 70 MPa and sintered at 1200 and 1250 deg C for 3 hours. Hardness measurements were performed by micro indentation, X-ray diffraction analysis and Scanning Electron Microscopy. The hardness of PZT I was 393 HV. (author)

Structural and dielectric characteristics of donor dopants in A and B places of perovskite ceramic PZT 54/46

International Nuclear Information System (INIS)

Durruthy-Rodriguez, M.D.; Perez-Fernandez, L.D.; Pelaiz-Barranco, A.; Calderon-Pinar, F.

2009-01-01

The microstructural (XRD and SEM) and dielectric behavior of Pb(Zr 0.54 Ti 0.46 )O 3 (PZT 54/46) ceramic system with donor (La, Nb and La+Nb) doping was studied. For all Nb-doped PZT samples, only one (tetragonal) phase was found, which confirms the compositional shifts near the morphotropic phase boundary. For La- and La+Nb-doped samples, there are two (rhombohedral and tetragonal) phases. Dielectric characteristic behavior (1/ε) for La- and La+Nb-doped PZT was associated with two-phase transitions: Ferro-Ferro at low temperature and Ferro-Para at Curie temperature. For Nb-doped samples, only one phase transition is observed, which indicates the presence of a single ferroelectric phase. (orig.)

A spherically-shaped PZT thin film ultrasonic transducer with an acoustic impedance gradient matching layer based on a micromachined periodically structured flexible substrate.

Science.gov (United States)

Feng, Guo-Hua; Liu, Wei-Fan

2013-10-09

This paper presents the microfabrication of an acoustic impedance gradient matching layer on a spherically-shaped piezoelectric ultrasonic transducer. The acoustic matching layer can be designed to achieve higher acoustic energy transmission and operating bandwidth. Also included in this paper are a theoretical analysis of the device design and a micromachining technique to produce the novel transducer. Based on a design of a lead titanium zirconium (PZT) micropillar array, the constructed gradient acoustic matching layer has much better acoustic transmission efficiency within a 20-50 MHz operation range compared to a matching layer with a conventional quarter-wavelength thickness Parylene deposition. To construct the transducer, periodic microcavities are built on a flexible copper sheet, and then the sheet forms a designed curvature with a ball shaping. After PZT slurry deposition, the constructed PZT micropillar array is released onto a curved thin PZT layer. Following Parylene conformal coating on the processed PZT micropillars, the PZT micropillars and the surrounding Parylene comprise a matching layer with gradient acoustic impedance. By using the proposed technique, the fabricated transducer achieves a center frequency of 26 MHz and a -6 dB bandwidth of approximately 65%.

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

Science.gov (United States)

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.

Piezoelectric Flexible LCP-PZT Composites for Sensor Applications at Elevated Temperatures

Science.gov (United States)

Tolvanen, Jarkko; Hannu, Jari; Juuti, Jari; Jantunen, Heli

2018-03-01

In this paper fabrication of piezoelectric ceramic-polymer composites is demonstrated via filament extrusion enabling cost-efficient large-scale production of highly bendable pressure sensors feasible for elevated temperatures. These composites are fabricated by utilizing environmentally resistant and stable liquid crystal polymer matrix with addition of lead zirconate titanate at loading levels of 30 vol%. These composites, of approximately 0.99 mm thick and length of > 50 cm, achieved excellent bendability with minimum bending radius of 6.6 cm. The maximum piezoelectric coefficients d33 and g33 of the composites were > 14 pC/N and > 108 mVm/N at pressure < 10 kPa. In all cases, the piezoelectric charge coefficient (d33) of the composites decreased as a function of pressure. Also, piezoelectric coefficient (d33) further decreased in the case of increased frequency press-release cycle sand pre-stress levels by approximately 37-50%. However, the obtained results provide tools for fabricating novel piezoelectric sensors in highly efficient way for environments with elevated temperatures.

Distributed Intrusion Sensor Using DFB Laser with Optical Feedback and Saturable Absorber

Directory of Open Access Journals (Sweden)

Kyoo Nam Choi

2018-01-01

Full Text Available Characteristics of a distributed intrusion sensor using a coherent DFB laser diode with an external optical feedback and saturable absorber were experimentally investigated. The stimulus at a location of 2 km using a PZT transducer placed the location of a simulated intruder in Φ-OTDR trace after averaging 32 times. Field trials demonstrated the detection of a vehicle and a pedestrian crossing above the sensing line and a loop in a burial depth of 50 cm. This distributed intrusion sensor using a coherent DFB laser diode as the light source had the advantages of a simple structure and intruder detection capability at the underground burial location.

Monitoring of Grouting Compactness in a Post-Tensioning Tendon Duct Using Piezoceramic Transducers

Directory of Open Access Journals (Sweden)

Tianyong Jiang

2016-08-01

Full Text Available A post-tensioning tendon duct filled with grout can effectively prevent corrosion of the reinforcement, maintain bonding behavior between the reinforcement and concrete, and enhance the load bearing capacity of concrete structures. In practice, grouting of the post-tensioning tendon ducts always causes quality problems, which may reduce structural integrity and service life, and even cause accidents. However, monitoring of the grouting compactness is still a challenge due to the invisibility of the grout in the duct during the grouting process. This paper presents a stress wave-based active sensing approach using piezoceramic transducers to monitor the grouting compactness in real time. A segment of a commercial tendon duct was used as research object in this study. One lead zirconate titanate (PZT piezoceramic transducer with marble protection, called a smart aggregate (SA, was bonded on the tendon and installed in the tendon duct. Two PZT patch sensors were mounted on the top outside surface of the duct, and one PZT patch sensor was bonded on the bottom outside surface of the tendon duct. In the active sensing approach, the SA was used as an actuator to generate a stress wave and the PZT sensors were utilized to detect the wave response. Cement or grout in the duct functions as a wave conduit, which can propagate the stress wave. If the cement or grout is not fully filled in the tendon duct, the top PZT sensors cannot receive much stress wave energy. The experimental procedures simulated four stages during the grout pouring process, which includes empty status, half grouting, 90% grouting, and full grouting of the duct. Experimental results show that the bottom PZT sensor can detect the signal when the grout level increases towards 50%, when a conduit between the SA and PZT sensor is formed. The top PZT sensors cannot receive any signal until the grout process is completely finished. The wavelet packet-based energy analysis was adopted in this

Effect of dilute magnetic ions on the optical, dielectric and ferroelectric properties of PZT at morphotopic phase boundary

Science.gov (United States)

Rao, T. Lakshmana; Pradhan, M. K.; Ramakrishna, P. V.; Dash, S.

2018-05-01

Modified-PZT ceramics with a formula Pb0.9Ni0.1[(Zr0.52Ti0.48)]1-xSnxO3 located near the morphotropic phase boundary (MPB) were prepared by conventional solid state process to investigate effects of dilute doping of Ni and Sn in different sites of PZT. The single phase structure of the series of samples has been identified by x-ray diffraction technique. The optical band gap has been obtained from the UV-Vis spectra and found to be shrinkage with doping. The detail dielectric and impedance studies are being carried out to investigate the conduction mechanism of the samples. A significant enhancement in the electric polarization is observed for the maximum Sn doping in a modified PZT.

Extrinsic coefficient charcterisation of PZT ceramics near the morphotropic phase boundary

Directory of Open Access Journals (Sweden)

Albareda, A.

2006-06-01

Full Text Available PZT ceramics with high piezoelectric coefficients have high extrinsic contributions. This extrinsic behaviour, which is related to the domain wall movement, produces high non-linear effects that are sometimes inconvenient, for example when it increases the losses in power devices. The relation between extrinsic behaviour and non-linearities could be used to provide a good extrinsic characterization of materials in order to optimise the piezoelectric devices. In all cases the physical explanation of the behaviour is sought. The aim of this work is to study the dependence of the linear and non-linear dielectric, piezoelectric and mechanical coefficients on the Ti fraction in PZT ceramic compositions near the morphotropic phase boundary (MPB. The dependence of these coefficients on the defect concentration is also analysed. Hard ceramics belonging to Ferroperm Piezoceramics, with two different acceptor dopant levels, high and low, have been measured.

Las cerámicas PZT con coeficientes piezoeléctricos elevados poseen contribuciones extrínsecas grandes. Este comportamiento extrínseco, relacionado con el movimiento de las paredes de los dominios, comporta efectos no lineales grandes que no siempre son deseables, por ejemplo, al incrementar las pérdidas de los dispositivos piezoeléctricos. Esta correspondencia entre efectos extrínsecos y no linealidades puede ser utilizada para caracterizar las cerámicas con el fin de optimizar sus propiedades piezoeléctricas. En todos los casos se busca una interpretación física de los resultados obtenidos. El objetivo de este trabajo es el estudio de la dependencia de los coeficientes lineales y no lineales dieléctricos, piezoeléctricos y elásticos con la fracción de Ti en cerámicas PZT con composiciones de Zr-Ti cerca de la transición de fase morfotrópica (MPB. También se analiza la dependencia de estos coeficientes con la concentración de impurezas, utilizando para ello cerámicas de

Thermoelectric-pyroelectric hybrid energy generation from thermopower waves in core-shell structured carbon nanotube-PZT nanocomposites.

Science.gov (United States)

Yeo, Taehan; Hwang, Hayoung; Shin, Dongjoon; Seo, Byungseok; Choi, Wonjoon

2017-02-10

There is an urgent need to develop a suitable energy source owing to the rapid development of various innovative devices using micro-nanotechnology. The thermopower wave (TW), which produces a high specific power during the combustion of solid fuel inside micro-nanostructure materials, is a unique energy source for unusual platforms that cannot use conventional energy sources. Here, we report on the significant enhancement of hybrid energy generation of pyroelectrics and thermoelectrics from TWs in carbon nanotube (CNT)-PZT (lead zirconate titanate, P(Z 0.5 -T 0.5 )) composites for the first time. Conventional TWs use only charge carrier transport driven by the temperature gradient along the core materials to produce voltage. In this study, a core-shell structure of CNTs-PZTs was prepared to utilize both the temperature gradient along the core material (thermoelectrics) and the dynamic change in the temperature of the shell structure (pyroelectrics) induced by TWs. The dual mechanism of energy generation in CNT-PZT composites amplified the average peak and duration of the voltage up to 403 mV and 612 ms, respectively, by a factor of 2 and 60 times those for the composites without a PZT layer. Furthermore, dynamic voltage measurements and structural analysis in repetitive TWs confirmed that CNT-PZT composites maintain the original performance in multiple TWs, which improves the reusability of materials. The advanced TWs obtained by the application of a PZT layer as a pyroelectric material contributes to the extension of the usable energy portion as well as the development of TW-based operating devices.

Piezoelectric PZT thin films on flexible copper-coated polymer films

Czech Academy of Sciences Publication Activity Database

Suchaneck, G.; Volkonskiy, O.; Gerlach, G.; Hubička, Zdeněk; Dejneka, Alexandr; Jastrabík, Lubomír; Kiselev, D.; Bdikin, I.; Kholkin, A.

636/637, - (2010), s. 392-397 ISSN 0255-5476 R&D Projects: GA ČR GC202/09/J017; GA AV ČR KJB100100703 Institutional research plan: CEZ:AV0Z10100522 Keywords : plasma jet deposition * PZT * kapton® film substrate * piezoresponse force microscopy Subject RIV: BM - Solid Matter Physics ; Magnetism

A fatigue test method for Pb(Zr,Ti)O3 thin films by using MEMS-based self-sensitive piezoelectric microcantilevers

Science.gov (United States)

Kobayashi, T.; Maeda, R.; Itoh, T.

2008-11-01

In the present study, we propose a new method for the fatigue test of lead zirconate titanate (PZT) thin films for MEMS devices by using self-sensitive piezoelectric microcantilevers developed in our previous study. We have deposited PZT thin films on SOI wafers and fabricated the microcantilevers through the MEMS microfabrication process. In the self-sensitive piezoelectric microcantilevers, the PZT thin films are separated in order to act as an actuator and a sensor. The fatigue characteristic of the PZT thin films can be evaluated by measuring the output voltage of the sensor as a function of time. When a sine wave of 20 Vpp and a dc bias of 10 V were applied to the PZT thin films for an actuator, the output voltage of the sensor fell down after 107 fatigue cycles. We have also investigated the influence of amplitude of the actuation sine wave and dc bias on the fatigue of the PZT thin films by using the proposed fatigue test method.

A fatigue test method for Pb(Zr,Ti)O3 thin films by using MEMS-based self-sensitive piezoelectric microcantilevers

International Nuclear Information System (INIS)

Kobayashi, T; Maeda, R; Itoh, T

2008-01-01

In the present study, we propose a new method for the fatigue test of lead zirconate titanate (PZT) thin films for MEMS devices by using self-sensitive piezoelectric microcantilevers developed in our previous study. We have deposited PZT thin films on SOI wafers and fabricated the microcantilevers through the MEMS microfabrication process. In the self-sensitive piezoelectric microcantilevers, the PZT thin films are separated in order to act as an actuator and a sensor. The fatigue characteristic of the PZT thin films can be evaluated by measuring the output voltage of the sensor as a function of time. When a sine wave of 20 V pp and a dc bias of 10 V were applied to the PZT thin films for an actuator, the output voltage of the sensor fell down after 10 7 fatigue cycles. We have also investigated the influence of amplitude of the actuation sine wave and dc bias on the fatigue of the PZT thin films by using the proposed fatigue test method

Characteristics of Au/PZT/TiO2/Nitride/Si structure capacitors with ICP nitride treatments

International Nuclear Information System (INIS)

Min, Hyung Seob; Kim, Tae Ho; Jeon, Chang Bae; Lee, Jae Gab; Kim, Ji Young

2002-01-01

In this study, the characteristics of PZT/TiO 2 ferroelectric gate stack capacitors with Inductively Coupled Plasma (ICP) nitridation were investigated for field effect transistor (FET)-type Ferroelectric Random Access Memory (FeRAM) applications. If a high accumulation capacitance is to be had, the ICP nitridation time needs to be optimized. While a short ICP treatment time results in thermal oxide growth due to lack of nitrogen, a long nitridation time causes a nitride layer which is too thick. Au/PZT(200 nm)/TiO 2 (40 nm)/Nitride/Si (MeFINS) structure capacitors show a memory window (ΔV) of 1.6 V under ±3-V operation while Au/PZT(200 nm)/TiO 2 (40 nm)/Si (MeFIS) capacitors without nitride treatment exhibit a small memory window of 0.6 V. At the same time, the capacitance of the MeFINS device is almost twice that of the MeFIS capacitor. This result implies that the ICP nitride treatment suppresses the formation of a low dielectric constant interfacial SiO x layer and alleviates the series capacitance problem

Interaction between depolarization effects, interface layer, and fatigue behavior in PZT thin film capacitors

Science.gov (United States)

Böttger, U.; Waser, R.

2017-07-01

The existence of non-ferroelectric regions in ferroelectric thin films evokes depolarization effects leading to a tilt of the P(E) hysteresis loop. The analysis of measured hysteresis of lead zirconate titanate (PZT) thin films is used to determine a depolarization factor which contains quantitative information about interfacial layers as well as ferroelectrically passive zones in the bulk. The derived interfacial capacitance is smaller than that estimated from conventional extrapolation techniques. In addition, the concept of depolarization is used for the investigation of fatigue behavior of PZT thin films indicating that the mechanism of seed inhibition, which is responsible for the effect, occurs in the entire film.

Self powered sensing by combining novel sensor architectures with energy harvesting

Science.gov (United States)

Bedekar, Vishwas Narayan

The sensing techniques investigated in this thesis utilize piezoelectric materials, piezoresistive materials, and magnetoelectric composites. Prior studies on structural health monitoring have demonstrated the use and promise of piezoelectric sensors. In this research, impedance spectroscopy based sensing technique was investigated with respect to two parameters (i) effect of the piezoelectric vibration mode on damage index metric, and (ii) selection of frequency band through manipulation of the electrode size and shape. These results were then used to determine sensor geometry and dimensions for detecting surface defects, fatigue and corrosion. Based upon these results, power requirement for structural health monitoring sensors was determined. Next, piezoelectric materials were coupled with magnetostrictive material for novel magnetic field gradient sensing. The ceramic -- ceramic (CC) gradiometer resembles in functionality a magnetoelectric transformer. It measures the magnetic field gradient and sensitivity with respect to a reference value. The CC gradiometer designed in this study was based upon the magnetoelectric (ME) composites and utilizes the ring-dot piezoelectric transformer structure working near resonance as the basis. This study investigated the gradiometer design and characterized the performance of gradiometer based upon Terfenol--D -- PZT composites. Based upon these results, next a metal -- ceramic gradiometer consisting of PZT and nickel was designed and characterized. In this thesis, two different designs of gradiometer with nickel and PZT laminate composites were fabricated. Nickel was chosen over other materials considering its co-firing ability with PZT. It can give a better control over dimensional parameters of the gradiometer sample and further size reduction is possible with tape casting technique. Detailed theoretical analysis was conducted in order to understand the experimental results. In order to significantly reduce the power

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

Science.gov (United States)

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.

Far infrared and Raman response in tetragonal PZT ceramic films

Czech Academy of Sciences Publication Activity Database

Buixaderas, Elena; Kadlec, Christelle; Vaněk, Přemysl; Drnovšek, S.; Uršič, H.; Malič, B.

2015-01-01

Roč. 54, č. 6 (2015), s. 219-224 ISSN 0366-3175 R&D Projects: GA ČR(CZ) GA14-25639S Institutional support: RVO:68378271 Keywords : dielectric response * phonons * FIR spectroscopy * time-domain THz spectroscopy * Raman spectroscopy * effective medium * PZT Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.280, year: 2015

Enhanced fatigue characteristics of sol-gel derived PZT thin films

International Nuclear Information System (INIS)

Shim, Donghyun; Pak, Jaemoon; Nam, Kuangwoo; Park, Gwangweo

2008-01-01

Pb(Zr,Ti)O 3 (PZT) thin films with Zr/Ti ratio of 52:48 were deposited on Pt/Ti/SiO 2 /Si substrates using the sol-gel method. Since the conditions of heat-treatment play a great role in film growth, post-annealing processes were conducted under different environments. After standard processing, films were annealed at 600 deg. C in three different atmosphere-air, O 2 and a two-step process conducted in air for 30 min and then in O 2 ambient, all done for 10 min. Through electron microscopy and X-ray diffraction, we found that all films were crack-free and highly (1 1 1) oriented. Hysteresis measurements showed a generally large polarization value. The fatigue properties differ drastically for all processes, showing an abnormal behaviour near the end of the measurement. The hysteresis loops before and after 1 x 10 10 switching cycles have been slightly changed in both shape and magnitude. Such abnormality and fatigue-free property is an unusual result for PZT films prepared on conventional Pt/Ti/SiO 2 /Si substrates

Determination of the piezoelectric properties of fine scale PZT fibres

Energy Technology Data Exchange (ETDEWEB)

Nelson, L.J.; Bowen, C.R. [Bath Univ. (United Kingdom). Dept. of Engineering and Applied Science

2002-07-01

Finite element (FE) modelling is used to determine the effect of fibre volume fraction, aspect ratio and polymer matrix stiffness on the d{sub 33} coefficients of 1-3 connectivity piezoelectric fibre composites. The aim is to use these observations as a means of determining the d{sub 33} of fine scale lead zirconate titanate (PZT) fibres. Results from a 1-D analytical model fit well with FE predictions for low aspect ratios. Two commercially available PZT-5A fibres, produced via the viscous suspension spinning process (VSSP) and an extrusion process, were fabricated into 1-3 composites with varying fibre volume fractions. The composite d{sub 33} measurements are compared to the model predictions and used to determine the d{sub 33} coefficients of the fibers. The d{sub 33} of the VSSP fibres and extruded fibres is measured as 365 pCN{sup -1} and 235 pCN{sup -1} respectively using this method. The large difference in the piezoelectric coefficients is possibly linked to the grain size and porosity, which is examined using scanning electron microscopy. (orig.)

Design and fabrication of a micro PZT cantilever array actuator for applications in fluidic systems

DEFF Research Database (Denmark)

Kim, H.; In, C.; Yoon, Gil Ho

2005-01-01

In this article, a micro cantilever array actuated by PZT films is designed and fabricated for micro fluidic systems. The design features for maximizing tip deflections and minimizing fluid leakage are described. The governing equation of the composite PZT cantilever is derived and the actuating......, dielectric constant, and dielectric loss. Tip deflections of 12 mu m at 5 V are measured, which agreed well with the predicted value. The 18 mu l/s leakage rate of air was observed at a pressure difference of 1000 Pa. Micro cooler is introduced, and its possible application to micro compressor is discussed....

Y{sub 3}Fe{sub 5}O{sub 12}/Na,Bi,Sr-doped PZT particulate magnetoelectric composites

Energy Technology Data Exchange (ETDEWEB)

Lisnevskaya, I.V., E-mail: liv@sfedu.ru; 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−x) wt% Na,Bi,Sr-doped PZT (PZTNB-1)+x wt% Y{sub 3}Fe{sub 5}O{sub 12} (YIG) with x=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, ΔE/ΔH 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. ΔE/ΔH value of 0–3 composites with x=40–60 wt% was found to be ∼1.6 mV/(cm Oe). - Highlights: • Y{sub 3}Fe{sub 5}O{sub 12}/Na,Bi,Sr-doped PZT particulate magnetoelectric composites were prepared. • The decrease in sintering temperature reduces the content of foreign phase of ZrO{sub 2}. • Connectivity pattern is important factor for magnetoelectric response. • The value of ME coefficient reaches ~1,6 mV/(cm Oe) in 0–3 composites.

Analytical modeling of demagnetizing effect in magnetoelectric ferrite/PZT/ferrite trilayers taking into account a mechanical coupling

Science.gov (United States)

Loyau, V.; Aubert, A.; LoBue, M.; Mazaleyrat, F.

2017-03-01

In this paper, we investigate the demagnetizing effect in ferrite/PZT/ferrite magnetoelectric (ME) trilayer composites consisting of commercial PZT discs bonded by epoxy layers to Ni-Co-Zn ferrite discs made by a reactive Spark Plasma Sintering (SPS) technique. ME voltage coefficients (transversal mode) were measured on ferrite/PZT/ferrite trilayer ME samples with different thicknesses or phase volume ratio in order to highlight the influence of the magnetic field penetration governed by these geometrical parameters. Experimental ME coefficients and voltages were compared to analytical calculations using a quasi-static model. Theoretical demagnetizing factors of two magnetic discs that interact together in parallel magnetic structures were derived from an analytical calculation based on a superposition method. These factors were introduced in ME voltage calculations which take account of the demagnetizing effect. To fit the experimental results, a mechanical coupling factor was also introduced in the theoretical formula. This reflects the differential strain that exists in the ferrite and PZT layers due to shear effects near the edge of the ME samples and within the bonding epoxy layers. From this study, an optimization in magnitude of the ME voltage is obtained. Lastly, an analytical calculation of demagnetizing effect was conducted for layered ME composites containing higher numbers of alternated layers (n ≥ 5). The advantage of such a structure is then discussed.

The memory characteristics of submicron feature-size PZT capacitors with PtOx top electrode by using dry-etching

International Nuclear Information System (INIS)

Huang, C.-K.; Wang, C.-C.; Wu, T.-B.

2007-01-01

Dry etching and its effect on the characteristics of submicron feature-size PbZr 1-x Ti x O 3 (PZT) capacitors with PtO x top electrode were investigated. The photoresist (PR)-masked PtO x films were etched by an Ar/(20%)Cl 2 /O 2 helicon wave plasma. A fence-free pattern with a significantly high etch rate and sidewall slope was obtained by the addition of O 2 into the etching gas mixture, due to the chemical instability of PtO x and the formation of a PtO 2 passivation layer to suppress redeposition of the etch by-products on the etched surface. The patterned PtO x electrode can be further used as a hard mask for etching the PZT film, subsequently, with the gas mixture of Ar, CF 4 and O 2 . A high etching rate of PZT and a good etching selectivity to PtO x can be obtained at 30% O 2 addition into the Ar/(50%)CF 4 plasma. The etched capacitors have a steep, 72 0 , sidewall angle with a clean surface. Moreover, the addition of O 2 into the etching gas can well preserve the properties and the fatigue endurance of PtO x /PZT capacitors

The Monoclinic Phase in PZT : New Light on Morphotropic Phase Boundaries

NARCIS (Netherlands)

Noheda, B.; Gonzalo, J.A.; Guo, R.; Park, S.-E.; Cross, L.E.; Cox, D.E.; Shirane, G.

2000-01-01

A summary of the work recently carried out on the morphotropic phase boundary (MPB) of PZT is presented. By means of x-ray powder diffraction on ceramic samples of excellent quality, the MPB has been successfully characterized by changing temperature in a series of closely spaced compositions. As a

A modified barbell-shaped PNN-PZT-PIN piezoelectric ceramic energy harvester

Science.gov (United States)

Gao, Xiangyu; Wu, Jingen; Yu, Yang; Dong, Shuxiang

2017-11-01

The quaternary system of relaxor-ferroelectric based Pb(Ni1/3Nb2/3)O3-Pb(ZrxTi1-x)O3-Pb(In0.5Nb0.5)O3 (PNN-PZT-PIN) piezoelectric ceramic at the morphotropic phase boundary was investigated via the solid reaction method. The optimized ceramic with excellent electric properties of ɛr = 8084, d33 = 977 pC/N, kp = 0.61, and Ec = 3.0 kV/cm was fabricated into d33-mode discs with separated surface electrodes, which were arranged in a series connection and, then as a piezo-stack, assembled into a barbell-shaped energy harvester that could bear a strong mechanical vibration. It is found that under a vibration mass-induced bending moment, the energy harvester produces an open circuit voltage of 26.4 Vp-p at the acceleration of 2.5 g at a load of 1.56 MΩ, which is two times higher in comparison to one without surface electrode separation. Its power output is 30 μW at the acceleration of 1 g and 104 μW at 2.5 g, which are even six times higher than that of a previously reported barbell-shaped energy harvester at room-temperature with the same acceleration. The enhanced power output can be attributed to (i) the excellent piezoelectric response of PNN-PZT-PIN ceramic and (ii) harvesting positive and negative charges from the separated surface electrodes other than a full surface electrode on piezoelectric discs under bending moment. Furthermore, the practical test was performed within a car engine, which shows that the PNN-PZT-PIN piezoelectric ceramic is a promising candidate for vibration energy harvesting.

Study of dielectric and piezoelectric properties of CNT reinforced PZT-PVA 0-3 composite

Science.gov (United States)

Vyas, Prince; Prajapat, Rampratap; Manmeeta, Saxena, Dhiraj

2016-05-01

Ferroelectric ceramic/polymer composites have the compliance of polymers which overcome the problems of brittleness in ceramics. By imbedding piezoelectric ceramic powder into a polymer matrix, 0-3 composites with good mechanical properties and high dielectric breakdown strength can be developed. The obtained composites of 0-3 connectivity exhibit the piezoelectric properties of ceramics and flexibility, strength and lightness of polymer. These composites can be used in vibration sensing and transducer applications specially as piezoelectric sensors. A potential way to improve piezoelectric& dielectric properties of theses composites is by inclusion of another conductive phase in these composites as reported in the literature. In present work, we prepared PZT-PVA 0-3 composites with 60% ceramic volume fraction reinforced with CNTs with volume ranging from 0 to 1.5 vol%. These CNT reinforced composites were obtained using hot press method with thickness of 200 µm having 0-3 conductivity. These composites were poled applying DC voltage. Dielectric properties of these samples were obtained in a wide frequency range (100 Hz to 1 Mhz) at room temperature. The piezoelectric properties of these composites were analyzed by measuring piezoelectric charge constants (d33). The dielectric and piezoelectric properties of these composites were studied as a function of CNT volume content. In these reinforced composites, CNTs act as a conductive filler dispersed in the matrix which in turn facilitates poling and results in an increase of the piezoelectric properties of the composite due to formation of percolation path through the composites. With a CNT content of 0.3 vol.% in PZT/PVA/CNTs, an increase of 61.3 % was observed in piezoelectric strain factors (d33). In these CNT reinforced composites, a substantial increase (approx. 67%) was also observed in dielectric constant and approximately 89% increase was observed in dielectric loss factor. Results so obtained are in the good

Experimental and Theoretical Investigations of the Impact Localization of a Passive Smart Composite Plate Fabricated Using Piezoelectric Materials

Directory of Open Access Journals (Sweden)

M. M. S. Dezfouli

2013-01-01

Full Text Available Two passive smart composite plates are fabricated using one and two PZT patches that are cheaper than the PZT wafer. The composite plate is fabricated in low temperature through the hand lay-up method to avoid PZT patch decoupling and wire spoiling. The locus of the impact point is identified using the output voltage to identify the impact location using one sensor. The output voltages of the sensors are analyzed to identify the impact location using two sensors. The locations of the impacts are determined based on the crossing points of two circles and the origin of an intended Cartesian coordinate system that is concentric with one of the sensors. This study proposes the impact location identification of the passive smart composite using the low-cost PZT patch PIC155 instead of common embedded materials (wafer and element piezoelectric.

Preparation of PZT/YBCO/YAlO heterostructure thin films by KrF excimer laser ablation

International Nuclear Information System (INIS)

Ebihara, Kenji; Kurogi, Hiromitsu; Yamagata, Yukihiko; Ikegami, Tomoaki; Grishin, A.M.

1998-01-01

The perovskite oxide YBa 2 Cu 3 O 7-x (YBCO) and Pb(Zr x Ti 1-x )O 3 (PZT) thin films have been deposited for superconducting-ferroelectric devices. KrF excimer laser ablation technique was used at the deposition conditions of 200--600 mTorr O 2 , 2-3J/cm 2 and 5--10 Hz operation frequency. Heterostructures of PZT-YBCO-YAlO 3 :Nd show the zero resistivity critical temperature of 82 K and excellent ferroelectric properties of remnant polarization 32 microC/cm 2 , coercive force of 80 kV/cm and dielectric constant 800. Cycling fatigue characteristics and leakage current are also discussed

Film-thickness and composition dependence of epitaxial thin-film PZT-based

NARCIS (Netherlands)

Nguyen, Duc Minh; Dekkers, Jan M.; Vu, Hung Ngoc; Rijnders, Augustinus J.H.M.

2013-01-01

The transverse piezoelectric coefficient e31,f and mass-sensitivity were measured on piezoelectric cantilevers based on epitaxial PZT thin-films with film-thicknesses ranging from 100 to 2000 nm. The highest values of e31,f and mass-sensitivity were observed at a film thickness of 500–750 nm, while

Ferroelectric and piezoelectric properties of epitaxial PZT films and devices on silicon

NARCIS (Netherlands)

Nguyen, Duc Minh

2010-01-01

In this thesis, the integration of lead zirconate titanate Pb(Zr,Ti)O3 (PZT) thin films into piezoelectric microelectromechanical systems (MEMS) based on silicon is studied. In these structures, all epitaxial oxide layers (thin film/electrode/buffer-layer(s)) were deposited by pulsed laser

Analytical Model of a PZT Thick-Film Triaxial Accelerometer for Optimum Design

DEFF Research Database (Denmark)

Hindrichsen, Christian Carstensen; Almind, Ninia Sejersen; Brodersen, S. H.

2009-01-01

We present a mechanical model of a triaxial micro accelerometer design using PZT thick-film as the sensing material. The model is based on the full anisotropic material tensors and Eulers' beam equation using simplifying assumptions where the smaller stress contributions are ignored. The model...

Study of mechanical-magnetic and electromagnetic properties of PZT/Ni film systems by a novel bulge technique

Energy Technology Data Exchange (ETDEWEB)

Liu, Q.; Zhou, W.; Ding, J.; Xiao, M. [School of Materials Science and Engineering, Xiangtan University, Hunan 411105 (China); Key Laboratory of Film Materials and Devices of Science and Technology Department of Hunan Province, Xiangtan University, Hunan 411105 (China); Yu, Z.J.; Xu, H. [State Key Lab for Turbulence and Complex Systems, Peking University, Beijing 100871 (China); Mao, W.G., E-mail: ssamao@126.com [School of Materials Science and Engineering, Xiangtan University, Hunan 411105 (China); Key Laboratory of Film Materials and Devices of Science and Technology Department of Hunan Province, Xiangtan University, Hunan 411105 (China); Pei, Y.M.; Li, F.X. [State Key Lab for Turbulence and Complex Systems, Peking University, Beijing 100871 (China); Feng, X. [AML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084 (China); Fang, D.N., E-mail: fangdn@pku.edu.cn [State Key Lab for Turbulence and Complex Systems, Peking University, Beijing 100871 (China); Institute of Advanced Structure Technology, Beijing Institute of Technology, Beijing 100081 (China)

2017-02-01

A novel multiple functional bulge apparatus was designed to study the mechanical-electronic-magnetic characteristics of electromagnetic materials. The elastic modulus difference effect of Ni thin film was observed and it was about 22.16% in the demagnetized and magnetization saturated states. The mechanical-magnetic behaviors of Ni and lead-titanate zirconate (PZT)/Ni films were in-situ measured by using the new bulge systems, respectively. The evolutions of three key material properties in hysteresis loop including saturation magnetization, remanent magnetization and coercive field were discussed in detail, respectively. The mechanisms of mechanical-magnetic coupled behaviors of Ni and PZT/Ni films were analyzed with the aid of the competitive relationship of stress and magnetization. Similarly, the electronic-magnetic characteristics of PZT/Ni films were in-situ measured by using this experimental system. The evolution of saturated magnetization, remanent magnetization and coercive field Kerr signals were discussed with the magneto-elastic anisotropy energy point. In this paper, a suitable mechanical-electronic-magnetic bulge measurement system was established, which would provide a good choice for further understanding the multi field coupling characteristics of electromagnetic film materials. - Highlights: • A novel bulge apparatus was designed to study electromagnetic materials. • The mechanical-magnetic features of Ni film were studied by this new apparatus. • The ΔE effect of Ni film was observed and analyzed. • The mechanical electronic-magnetic characteristics of PZT/Ni film were discussed.

Microstructure and Properties of Plasma Sprayed Lead Zirconate Titanate (PZT) Ceramics

Czech Academy of Sciences Publication Activity Database

Ctibor, Pavel; Pala, Zdeněk; Boldyryeva, Hanna; Sedláček, J.; Kmetík, Viliam

2012-01-01

Roč. 2, č. 2 (2012), s. 64-75 ISSN 2079-6412 R&D Projects: GA TA ČR TA01010878 Institutional research plan: CEZ:AV0Z20430508 Keywords : plasma spraying * electroceramics * PZT * phase composition * permittivity Subject RIV: JK - Corrosion ; Surface Treatment of Materials http://www.mdpi.com/2079-6412/2/2/64

Kramers-Kronig method for determination of optical properties of PZT nanotubes fabricated by sol-gel method and porous anodic alumina with high aspect ratio

Science.gov (United States)

Pakizeh, Esmaeil; Moradi, Mahmood

2018-03-01

Ferroelectric Pb(ZrTi)O3 (PZT) nanotubes were prepared by sol-gel method and porous anodic alumina (PAA) membrane using spin-coating technique. This method is based on filling-pyrolysis-filling process and the use of one-stage alumina membranes. One of the advantages of this method is its rapidity, which takes only 1 h time before the calcination step. The effect of repeated pores filling was investigated to get the required size of nanotubes. The field emission scanning electron microscope (FE-SEM) images were shown that the PZT nanotubes have inner diameters in the range of 65-90 nm and length of about 50-60 μm. This means that the samples have a significant aspect ratio (700-800). Also the FE-SEM image confirmed that the highly ordered, hexagonally distributed PAA membranes with the pore diameter about 140-150 nm were formed. The X-ray diffraction (XRD) results showed that the PZT nanotubes have a tetragonal structure. The metal oxide bands like ZrO6 and TiO6 of the final PZT nanotubes were detected by Fourier transform infrared (FT-IR) analysis and confirmed the formation of perovskite structure. By using FT-IR spectroscopy and Kramers-Kronig transformation method, the optical constants like real 𝜀1(ω) and imaginary 𝜀2(ω) parts of dielectric function, extinction coefficient k(ω) and refractive index n(ω) were determined. It was shown that the optical constants of PZT nanotubes are different from PZT nanoparticles.

ELABORATION AND DIELECTRIC CHARACTERIZATION OF A DOPED FERROELECTRIC MATERIAL TYPE PZT

Directory of Open Access Journals (Sweden)

M. Abba

2013-12-01

Full Text Available The main objective of this work is based on the synthesis and dielectric characterization of a new material in ceramic PZT with a perovskite structure ABO3. We are interested to study the Quaternary system (doping in site A and site B of general formula: Pb0.96Ba0.02Ca0.02[(Zr0.52Ti0.480.94(Zn1/3Ta2/30.03(In1/3Sb2/30.03]O3 short PZT-PBC-ZTIS. The sample selected for this study was prepared by the method of synthesis with solid way. Heat treatment was applied to these compositions at different temperatures: 1100, 1150,1180 and 1200 °C successively to optimize the sintering temperature optimal where the density of the sample is maximum (near theoretical density and therefore the product has better physical quality. The study of dielectric properties of all samples showed a high permittivity dielectric εr = 18018, low dielectric loss: tgδ = 7.62%, for the composition sintered to 1180 ° C included in the phase morphotropique zone (FMP.

ELABORATION AND DIELECTRIC CHARACTERIZATION OF A DOPED FERROELECTRIC MATERIAL TYPE PZT

Directory of Open Access Journals (Sweden)

M. Abba

2015-07-01

Full Text Available The main objective of this work is based on the synthesis and dielectric characterization of a new material in ceramic PZT with a perovskite structure ABO3. We are interested to study the Quaternary system (doping in site A and site B of general formula: Pb0.96Ba0.02Ca0.02[(Zr0.52Ti0.480.94(Zn1/3Ta2/30.03(In1/3Sb2/30.03]O3 short PZT-PBC-ZTIS. The sample selected for this study was prepared by the method of synthesis with solid way. Heat treatment was applied to these compositions at different temperatures: 1100, 1150,1180 and 1200 °C successively to optimize the sintering temperature optimal where the density of the sample is maximum (near theoretical density and therefore the product has better physical quality. The study of dielectric properties of all samples showed a high permittivity dielectric εr = 18018, low dielectric loss: tgδ = 7.62%, for the composition sintered to 1180 ° C included in the phase morphotropique zone (FMP.

Microstructure of pulsed-laser deposited PZT on polished and annealed MGO substrates

NARCIS (Netherlands)

King, S.L.; Coccia, L.G.; Gardeniers, Johannes G.E.; Boyd, I.W.

1996-01-01

Thin films of Lead-Zirconate-Titanate (PZT) have been grown by pulsed-laser-deposition (PLD) onto polished MgO substrates both with and without pre-annealing. The surface morphology of polished MgO substrates, which are widely used for deposition, is examined by AFM. Commercially available,

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

Science.gov (United States)

Sevillano, Enrique; Sun, Rui; Perera, Ricardo

2016-05-05

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.

Ga+ implantation in a PZT film during focused ion beam micro-machining

International Nuclear Information System (INIS)

Wollschlaeger, Nicole; Oesterle, Werner; Haeusler, Ines; Stewart, Mark

2015-01-01

The objective of the present work was to study the impact of Focused Ion Beam (FIB) machining parameters on the thickness of the damaged layer within a thin film PZT. Therefore, different Ga + - ion doses and ion energies were applied to a standard PZT film (80/20 lead zirconium titanate) under two beam incidence angles (90 and 1 ). The thicknesses of the corresponding Ga + -implanted layers were then determined by cross-sectional TEM in combination with energy dispersive spectroscopic (EDS) line-scans and correlated with polarisation hysteresis loops. The results show a decrease of Ga + -implanted layer thickness with decreasing inclination angle, whereas ion energy and ion dose could be correlated with gallium concentration in the implanted layers. Under the most unfavorable conditions the depth of the affected zone was 26 nm, it was only 2 nm for the most favorable conditions. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Piezoelectric and dielectric characterization of corona and contact poled PZT-epoxy-MWCNT bulk composites

Science.gov (United States)

Banerjee, S.; Cook-Chennault, K. A.; Du, W.; Sundar, U.; Halim, H.; Tang, A.

2016-11-01

Three-phase lead zirconate titanate (PZT, PbZr0.52Ti0.48O3)-epoxy-multi-walled carbon nanotube (MWCNT) bulk composites were prepared, where the volume fraction of PZT was held constant at 30%, while the volume fraction of the MWCNTs was varied from 1.0%-10%. The samples were poled using either a parallel plate contact or contactless (corona) poling technique. The piezoelectric strain coefficient (d33), dielectric constant (ɛ), and dielectric loss tangent (tan δ) of the samples were measured at 110 Hz, and compared as a function of poling technique and volume fraction of MWCNTs. The highest values for dielectric constant and piezoelectric strain coefficients were 465.82 and 18.87 pC/N for MWCNT volume fractions of 10% and 6%, respectively. These values were obtained for samples that were poled using the corona contactless method. The impedance and dielectric spectra of the composites were recorded over a frequency range of 100 Hz-20 MHz. The impedance values observed for parallel-plate contact poled samples are higher than that of corona poled composites. The fractured surface morphology and distribution of the PZT particles and MWCNTs were observed with the aid of electron dispersion spectroscopy and a scanning electron microscope. The surface morphology of the MWCNTs was observed with the aid of a field emission transmission electron microscope.

The Effect of Shock Stress and Field Strength on Shock-Induced Depoling of Normally Poled PZT 95/5

International Nuclear Information System (INIS)

CHHABILDAS, LALIT C.; FURNISH, MICHAEL D.; MONTGOMERY, STEPHEN T.; SETCHELL, ROBERT E.

1999-01-01

Shock-induced depoling of the ferroelectric ceramic PZT 95/5 is utilized in a number of pulsed power devices. Several experimental and theoretical efforts are in progress in order to improve numerical simulations of these devices. In this study we have examined the shock response of normally poled PZT 95/5 under uniaxial strain conditions. On each experiment the current produced in an external circuit and the transmitted waveform at a window interface were recorded. The peak electrical field generated within the PZT sample was varied through the choice of external circuit resistance. Shock pressures were varied from 0.6 to 4.6 GPa, and peak electrical fields were varied from 0.2 to 37 kV/cm. For a 2.4 GPa shock and the lowest peak field, a nearly constant current governed simply by the remanent polarization and the shock velocity was recorded. Both decreasing the shock pressure and increasing the electrical field resulted in reduced current generation, indicating a retardation of the depoling kinetics

Improving the magnetoelectric performance of Metglas/PZT laminates by annealing in a magnetic field.

Science.gov (United States)

Freeman, E; Harper, J; Goel, N; Gilbert, I; Unguris, J; Schiff, S J; Tadigadapa, S

2017-01-01

A comprehensive investigation of magnetostriction optimization in Metglas 2605SA1 ribbons is performed to enhance magnetoelectric performance. We explore a range of annealing conditions to relieve remnant stress and align the magnetic domains in the Metglas, while minimizing unwanted crystallization. The magnetostriction coefficient, magnetoelectric coefficient, and magnetic domain alignment are correlated to optimize magnetoelectric performance. We report on direct magnetostriction observed by in-plane Doppler vibrometer and domain imagining using scanning electron microscopy with polarization analysis for a range of annealing conditions. We find that annealing in an oxygen-free environment at 400 °C for 30 min yields an optimal magnetoelectric coefficient, magnetostriction and magnetostriction coefficient. The optimized ribbons had a magnetostriction of 50.6 ± 0.2 μ m m -1 and magnetoelectric coefficient of 79.3 ± 1.5 μ m m -1 mT -1 . The optimized Metglas 2605SA1 ribbons and PZT-5A (d 31 mode) sensor achieves a magnetic noise floor of approximately 600 pT Hz -1/2 at 100 Hz and a magnetoelectric coefficient of 6.1 ± 0.03 MV m -1 T -1 .

Improving the magnetoelectric performance of Metglas/PZT laminates by annealing in a magnetic field

Science.gov (United States)

Freeman, E.; Harper, J.; Goel, N.; Gilbert, I.; Unguris, J.; Schiff, S. J.; Tadigadapa, S.

2017-08-01

A comprehensive investigation of magnetostriction optimization in Metglas 2605SA1 ribbons is performed to enhance magnetoelectric performance. We explore a range of annealing conditions to relieve remnant stress and align the magnetic domains in the Metglas, while minimizing unwanted crystallization. The magnetostriction coefficient, magnetoelectric coefficient, and magnetic domain alignment are correlated to optimize magnetoelectric performance. We report on direct magnetostriction observed by in-plane Doppler vibrometer and domain imagining using scanning electron microscopy with polarization analysis for a range of annealing conditions. We find that annealing in an oxygen-free environment at 400 {}\\circ {{C}} for 30 min yields an optimal magnetoelectric coefficient, magnetostriction and magnetostriction coefficient. The optimized ribbons had a magnetostriction of 50.6 ± 0.2 μ {{m}} {{{m}}}-1 and magnetoelectric coefficient of 79.3 ± 1.5 µm m-1 mT-1. The optimized Metglas 2605SA1 ribbons and PZT-5A (d31 mode) sensor achieves a magnetic noise floor of approximately 600 pT {{{H}}{{z}}}-1/2 at 100 Hz and a magnetoelectric coefficient of 6.1 ± 0.03 MV m-1 T-1.

Phase transition shift in lead-excess PZT films under UV illumination

Czech Academy of Sciences Publication Activity Database

Deyneka, Alexander; Suchaneck, G.; Jastrabík, Lubomír; Gerlach, G.

2004-01-01

Roč. 67, - (2004), s. 173-180 ISSN 1058-4587 R&D Projects: GA ČR(CZ) GP202/02/D078; GA AV ČR(CZ) KJB1010301 Institutional research plan: CEZ:AV0Z1010914 Keywords : PZT thin films * phase transition * ellipsometry Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.427, year: 2004

Measurement of effective piezoelectric coefficients of PZT thin films for energy harvesting application with interdigitated electrodes.

Science.gov (United States)

Chidambaram, Nachiappan; Mazzalai, Andrea; Muralt, Paul

2012-08-01

Interdigitated electrode (IDE) systems with lead zirconate titanate (PZT) thin films play an increasingly important role for two reasons: first, such a configuration generates higher voltages than parallel plate capacitor-type electrode (PPE) structures, and second, the application of an electric field leads to a compressive stress component in addition to the overall stress state, unlike a PPE structure, which results in tensile stress component. Because ceramics tend to crack at relatively moderate tensile stresses, this means that IDEs have a lower risk of cracking than PPEs. For these reasons, IDE systems are ideal for energy harvesting of vibration energy, and for actuators. Systematic investigations of PZT films with IDE systems have not yet been undertaken. In this work, we present results on the evaluation of the in-plane piezoelectric coefficients with IDE systems. Additionally, we also propose a simple and measurable figure of merit (FOM) to analyze and evaluate the relevant piezoelectric parameter for harvesting efficiency without the need to fabricate the energy harvesting device. Idealized effective coefficients e(IDE) and h(IDE) are derived, showing its composite nature with about one-third contribution of the transverse effect, and about two-thirds contribution of the longitudinal effect in the case of a PZT film deposited on a (100)-oriented silicon wafer with the in-plane electric field along one of the Si directions. Randomly oriented 1-μm-thick PZT 53/47 film deposited by a sol-gel technique, was evaluated and yielded an effective coefficient e(IDE) of 15 C·m(-2). Our FOM is the product between effective e and h coefficient representing twice the electrical energy density stored in the piezoelectric film per unit strain deformation (both for IDE and PPE systems). Assuming homogeneous fields between the fingers, and neglecting the contribution from below the electrode fingers, the FOM for IDE structures with larger electrode gap is derived to be

Ferroelectric properties of bilayer structured Pb(Zr0.52Ti0.48)O3/SrBi2Ta2O9 (PZT/SBT) thin films on Pt/TiO2/SiO2/Si substrates

International Nuclear Information System (INIS)

Zhang Wenqi; Li Aidong; Shao Qiyue; Xia Yidong; Wu Di; Liu Zhiguo; Ming Naiben

2008-01-01

Pb(Zr 0.52 Ti 0.48 )O 3 (PZT) thin films with large remanent polarization and SrBi 2 Ta 2 O 9 (SBT) thin films with excellent fatigue-resisting characteristic have been widely studied for non-volatile random access memories, respectively. To combine these two advantages , bilayered Pb(Zr 0.52 Ti 0.48 )O 3 /SrBi 2 Ta 2 O 9 (PZT/SBT) thin films were fabricated on Pt/TiO 2 /SiO 2 /Si substrates by chemical solution deposition method. X-ray diffraction patterns revealed that the diffraction peaks of PZT/SBT thin films were completely composed of PZT and SBT, and no other secondary phase was observed. The electrical properties of the bilayered structure PZT/SBT films have been investigated in comparison with pure PZT and SBT films. PZT/SBT bilayered thin films showed larger remanent polarization (2P r ) of 18.37 μC/cm 2 than pure SBT and less polarization fatigue up to 1 x 10 9 switching cycles than pure PZT. These results indicated that this bilayered structure of PZT/SBT is a promising material combination for ferroelectric memory applications

The Effect of Acceptor and Donor Doping on Oxygen Vacancy Concentrations in Lead Zirconate Titanate (PZT).

Science.gov (United States)

Slouka, Christoph; Kainz, Theresa; Navickas, Edvinas; Walch, Gregor; Hutter, Herbert; Reichmann, Klaus; Fleig, Jürgen

2016-11-22

The different properties of acceptor-doped (hard) and donor-doped (soft) lead zirconate titanate (PZT) ceramics are often attributed to different amounts of oxygen vacancies introduced by the dopant. Acceptor doping is believed to cause high oxygen vacancy concentrations, while donors are expected to strongly suppress their amount. In this study, La 3+ donor-doped, Fe 3+ acceptor-doped and La 3+ /Fe 3+ -co-doped PZT samples were investigated by oxygen tracer exchange and electrochemical impedance spectroscopy in order to analyse the effect of doping on oxygen vacancy concentrations. Relative changes in the tracer diffusion coefficients for different doping and quantitative relations between defect concentrations allowed estimates of oxygen vacancy concentrations. Donor doping does not completely suppress the formation of oxygen vacancies; rather, it concentrates them in the grain boundary region. Acceptor doping enhances the amount of oxygen vacancies but estimates suggest that bulk concentrations are still in the ppm range, even for 1% acceptor doping. Trapped holes might thus considerably contribute to the charge balancing of the acceptor dopants. This could also be of relevance in understanding the properties of hard and soft PZT.

The Effect of Acceptor and Donor Doping on Oxygen Vacancy Concentrations in Lead Zirconate Titanate (PZT

Directory of Open Access Journals (Sweden)

Christoph Slouka

2016-11-01

Full Text Available The different properties of acceptor-doped (hard and donor-doped (soft lead zirconate titanate (PZT ceramics are often attributed to different amounts of oxygen vacancies introduced by the dopant. Acceptor doping is believed to cause high oxygen vacancy concentrations, while donors are expected to strongly suppress their amount. In this study, La3+ donor-doped, Fe3+ acceptor-doped and La3+/Fe3+-co-doped PZT samples were investigated by oxygen tracer exchange and electrochemical impedance spectroscopy in order to analyse the effect of doping on oxygen vacancy concentrations. Relative changes in the tracer diffusion coefficients for different doping and quantitative relations between defect concentrations allowed estimates of oxygen vacancy concentrations. Donor doping does not completely suppress the formation of oxygen vacancies; rather, it concentrates them in the grain boundary region. Acceptor doping enhances the amount of oxygen vacancies but estimates suggest that bulk concentrations are still in the ppm range, even for 1% acceptor doping. Trapped holes might thus considerably contribute to the charge balancing of the acceptor dopants. This could also be of relevance in understanding the properties of hard and soft PZT.

Homogeneity analysis of high yield manufacturing process of mems-based pzt thick film vibrational energy harvesters

DEFF Research Database (Denmark)

Lei, Anders; Xu, Ruichao; Pedersen, C.M.

2011-01-01

This work presents a high yield wafer scale fabrication of MEMS-based unimorph silicon/PZT thick film vibrational energy harvesters aimed towards vibration sources with peak frequencies in the range of a few hundred Hz. By combining KOH etching with mechanical front side protection, SOI wafer...... to accurately define the thickness of the silicon part of the harvester and a silicon compatible PZT thick film screen-printing technique, we are able to fabricate energy harvesters on wafer scale with a yield higher than 90%. The characterization of the fabricated harvesters is focused towards the full wafer....../mass-production aspect; hence the analysis of uniformity in harvested power and resonant frequency....

Micromechanical Sensor for the Spectral Decomposition of Acoustic Signals

Science.gov (United States)

2012-02-01

PZT Driver ......................................................... 226 Figure 7.3: PZT Driver...Gravity Abbreviations AF Amorphous Film ECM Electret Condenser Microphone FEA Finite Element Analysis FWHM Full Width Half Maximum PZT Lead...and/or critical equipment, such as rotating machinery and structural components, for signs of wear and fatigue . The first application, impact

Effects of sintering temperature on the pyrochlore phase in PZT nanotubes and their transformation to the perovskite phase by coating with PbO multilayers.

Science.gov (United States)

Han, Jin Kyu; Choi, Yong Chan; Jeon, Do Hyen; Lee, Min Ku; Bu, Sang Don

2014-11-01

We report the phase evolution of Pb(Zr0.52Ti0.48)O3 nanotubes (PZT-NTs), from the pyrochlore to perovskite phase, with an outer diameter of about 420 nm and a wall thickness of about 10 nm. The PZT-NTs were fabricated in pores of porous anodic alumina membrane (PAM) using a spin coating of PZT sol-gel solution and subsequent annealing at 500-700 degrees C in oxygen gas. The pyrochlore phase was found to be formed at 500 degrees C, and also found not to be transformed into the perovskite phase, even though annealing was performed at higher temperatures to 700 degrees C. Elementary distribution analysis of PZT-NTs embedded in PAM reveal that Pb diffusion from nanotubes into pore walls of PAM is one of the main reasons. By employing firstly an additional PbO coating on the pyrochlore nanotubes and then subsequent annealing at 700 degrees C, we have successfully achieved an almost pure perovskite phase in nanotubes. These results suggest that PbO acts as a Pb-compensation agent in the Pb- deficient PZT-NTs. Moreover, our method can be used in the synthesis of all metal-oxide materials, including volatile elements.

Large aperture deformable mirror with a transferred single-crystal silicon membrane actuated using large-stroke PZT Unimorph Actuators

Science.gov (United States)

Hishinumat, Yoshikazu; Yang, Eui - Hyeok (EH)

2005-01-01

We have demonstrated a large aperture (50 mm x 50 mm) continuous membrane deformable mirror (DM) with a large-stroke piezoelectric unimorph actuator array. The DM consists of a continuous, large aperture, silicon membrane 'transferred' in its entirety onto a 20 x 20 piezoelectric unimorph actuator array. A PZT unimorph actuator, 2.5 mm in diameter with optimized PZT/Si thickness and design showed a deflection of 5.7 [m at 20V. An assembled DM showed an operating frequency bandwidth of 30 kHz and influence function of approximately 30%.

Ferroelectric Dipole Electrets Prepared from Soft and Hard PZT Ceramics in Electrostatic Vibration Energy Harvesters

International Nuclear Information System (INIS)

Asanuma, H; Oguchi, H; Hara, M; Kuwano, H

2013-01-01

Aiming at longer stability of surface potential, we propose a ferroelectric dipole electret (FDE) prepared from hard ferroelectric material. We compared output power of electrostatic vibration energy harvester and surface potential stability between FDEs prepared from soft and hard PZT ceramics, as well as a CYTOP polymer electret. The hard FDE showed a seven-fold increase in output power over the soft FDE and nine-fold increase over the CYTOP polymer electret. The hard FDE also showed longer stability of surface potential than that of the soft FDE, whereas the stability of the hard FDE was not yet comparable to that of CYTOP polymer electret. A FDE prepared from harder PZT ceramic (with higher coercive electric field and Curie temperature) may provide more stability in surface potential

Analysis of signals propagating in a phononic crystal PZT layer deposited on a silicon substrate.

Science.gov (United States)

Hladky-Hennion, Anne-Christine; Vasseur, Jérôme; Dubus, Bertrand; Morvan, Bruno; Wilkie-Chancellier, Nicolas; Martinez, Loïc

2013-12-01

The design of a stop-band filter constituted by a periodically patterned lead zirconate titanate (PZT) layer, polarized along its thickness, deposited on a silicon substrate and sandwiched between interdigitated electrodes for emission/reception of guided elastic waves, is investigated. The filter characteristics are theoretically evaluated by using finite element simulations: dispersion curves of a patterned PZT layer with a specific pattern geometry deposited on a silicon substrate present an absolute stop band. The whole structure is modeled with realistic conditions, including appropriate interdigitated electrodes to propagate a guided mode in the piezoelectric layer. A robust method for signal analysis based on the Gabor transform is applied to treat transmitted signals; extract attenuation, group delays, and wave number variations versus frequency; and identify stop-band filter characteristics.

Improvement of the fatigue and the ferroelectric properties of PZT films through a LSCO seed layer

Energy Technology Data Exchange (ETDEWEB)

Rodrigues, Sofia A.S., E-mail: sofiarodrigues@fisica.uminho.pt; Silva, José P.B.; Khodorov, Anatoli; Martín-Sánchez, Javier; Pereira, M.; Gomes, M.J.M.

2013-11-01

Highlights: • Pulsed laser deposited PZT thin films. • Seed layer effect on the structural and ferroelectric properties of the PZT films. • The stability of P{sub r} was improved with the introduction of the LSCO layer. -- Abstract: The ability to optimizate the preparation of Lead Zirconate Titanate (PZT) films on platinized Si substrate by pulsed laser deposition was demonstrated. The effect of the modification of the interface film/electrode through the use of a (La,Sr)CoO{sub 3} (LSCO) seed layer on the remnant polarization, fatigue endurance and stress in PZT films was studied. An improvement on the ferroelectric properties was found with the using of the LSCO layer. A remnant polarization (P{sub r}) of 19.8 μC/cm{sup 2} and 4.4 μC/cm{sup 2} for films with and without the LSCO layer were found. In the same way the polarization fatigue decreases significantly after deposition of the LSCO layer between the film and substrate. Atomic force microscopy (AFM) images revealed a different growth process in the films. Current–voltage (I–V) measurements showed that the use of LSCO seed layer improves the leakage current and, on the other hand the conduction mechanisms in the film without LSCO, after the fatigue test, was found to be changed from Schottky to Poole–Frenkel. The trap activation energy (about 0.14 eV) determined from Poole–Frenkel mode agrees well with the energy level of oxygen vacancies. The films stresses were estimated by XRD in order to explain the improvement on the structure and consequentially ferroelectric properties of the films. The model proposed by Dawber and Scott was found to be in agreement with our experimental data, which seems to predict that the oxygen vacancies play an important role on fatigue.

Flexible Semitransparent Energy Harvester with High Pressure Sensitivity and Power Density Based on Laterally Aligned PZT Single-Crystal Nanowires.

Science.gov (United States)

Zhao, Quan-Liang; He, Guang-Ping; Di, Jie-Jian; Song, Wei-Li; Hou, Zhi-Ling; Tan, Pei-Pei; Wang, Da-Wei; Cao, Mao-Sheng

2017-07-26

A flexible semitransparent energy harvester is assembled based on laterally aligned Pb(Zr 0.52 Ti 0.48 )O 3 (PZT) single-crystal nanowires (NWs). Such a harvester presents the highest open-circuit voltage and a stable area power density of up to 10 V and 0.27 μW/cm 2 , respectively. A high pressure sensitivity of 0.14 V/kPa is obtained in the dynamic pressure sensing, much larger than the values reported in other energy harvesters based on piezoelectric single-crystal NWs. Furthermore, theoretical and finite element analyses also confirm that the piezoelectric voltage constant g 33 of PZT NWs is competitive to the lead-based bulk single crystals and ceramics, and the enhanced pressure sensitivity and power density are substantially linked to the flexible structure with laterally aligned PZT NWs. The energy harvester in this work holds great potential in flexible and transparent sensing and self-powered systems.

MEMS Cantilever Sensor for THz Photoacoustic Chemical Sensing and Spectroscopy

Science.gov (United States)

2013-12-26

texture for the preferential crystal formation of the PZT . Deposited by chemical solution deposition (sol-gel), a 1 μm thick PZT film was used as the...Potrepka, G. R. Fox, I. Takeuchi and R. G. Polcawich. "Improving PZT thin film texture through Pt metallization and seed layers," MRS Proceedings (1299... PZT thin film," Journal of the European Ceramic Society 24(6), pp. 993-997, 2004. [73] Q. Wang, X. Du, B. Xu and L. E. Cross. "Theoretical analysis

Ferroelectric–Ferromagnetic Composites Based on PZT Type Powder and Ferrite Powder

Directory of Open Access Journals (Sweden)

Bochenek D.

2013-12-01

Full Text Available W pracy otrzymano ferroelektryczno-ferromagnetyczne kompozyty na bazie ceramicznego proszku typu PZT. Połączenie ferroelektrycznego i magnetycznego proszku miało na celu otrzymanie materiałów wykazujących zarówno elektryczne i magne- tyczne właściwości. Ferroelektryczny, ceramiczny proszek (w ilości 90% stanowiły domieszkowane składy proszku typu PZT, natomiast magnetycznym składnikiem w kompozycie był niklówo-cynkowy ferryt (Nii-^Zn^Fe^Oj. Syntetyzowanie składni- ków kompozytu ceramiczno-ferrytowego przeprowadzono metodą spiekania wy prasek w fazie stałej, natomiast zagęszczanie zsyntetyzowanego kompozytowego proszku metodą spiekania swobodnego. Przeprowadzono badania rentgenowskie, mikrostrukturalne. EDS. dielektryczne, magnetyczne, tarcia wewnętrznego oraz elektrycznej pętli hi sterczy. Badania wykazały, występowanie korclacji między podukładem magnetycznym i podukładem elektrycznym w ferroelektryczno-ferromagnetycznych kompozytach. Dzięki ferroelektrycznym i magnetycznym właściwościom otrzymanych kompozytów, materiały tego typu mogą znaleźć zastosowanie aplikacyjne w nowych typach pamięci.

Electric and magnetic properties of a CoFe2O4/PZT bilayer grown on (100)SrTiO3 by using PLD

International Nuclear Information System (INIS)

Zhang, X. D.; Dho, J. H.

2010-01-01

We have investigated the electric and the magnetic properties of a ferrimagnetic and ferroelectric bilayer CoFe 2 O 4 (CFO)/PbZr 0.2 Ti 0.8 O 3 (PZT) grown on a (100)SrTiO 3 (STO) substrate by using pulsed laser deposition. PZT (100 nm) and CFO (70 nm) layers were sequentially deposited on the (100)STO substrate with a bottom electrode LaNiO 3 (50 nm) layer at 600 - 650 .deg. C. X-ray diffraction for the PZT layer exhibited both (200) and (002) peaks, which are due to the c- and the a-domains, and a decrease of tetragonality after CFO deposition. The electric properties of the CFO/PZT bilayer were characterized by using P-V loop, C-f, and C-V measurements. The remnant polarization and coercivity were slightly decreased after the top-layer CFO deposition while fatigue behavior was distinctively improved. The M-H loop measurement confirmed that the CFO layer possessed a typical ferrimagnetic property at room temperature.

Ellipsometric investigations of the refractive index depth profile in PZT thin films

Czech Academy of Sciences Publication Activity Database

Deineka, Alexander; Jastrabík, Lubomír; Suchaneck, G.; Gerlach, G.

2001-01-01

Roč. 188, č. 4 (2001), s. 1549-1552 ISSN 0031-8965 R&D Projects: GA MŠk LN00A015; GA ČR GA202/00/1425 Institutional research plan: CEZ:AV0Z1010914 Keywords : PZT films * optical investigations Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.025, year: 2001

Ga{sup +} implantation in a PZT film during focused ion beam micro-machining

Energy Technology Data Exchange (ETDEWEB)

Wollschlaeger, Nicole; Oesterle, Werner; Haeusler, Ines [Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin (Germany); Stewart, Mark [National Physical Laboratory, Hampton Road, Teddington Middlesex TW 11 0LW (United Kingdom)

2015-03-01

The objective of the present work was to study the impact of Focused Ion Beam (FIB) machining parameters on the thickness of the damaged layer within a thin film PZT. Therefore, different Ga{sup +}- ion doses and ion energies were applied to a standard PZT film (80/20 lead zirconium titanate) under two beam incidence angles (90 and 1 ). The thicknesses of the corresponding Ga{sup +}-implanted layers were then determined by cross-sectional TEM in combination with energy dispersive spectroscopic (EDS) line-scans and correlated with polarisation hysteresis loops. The results show a decrease of Ga{sup +}-implanted layer thickness with decreasing inclination angle, whereas ion energy and ion dose could be correlated with gallium concentration in the implanted layers. Under the most unfavorable conditions the depth of the affected zone was 26 nm, it was only 2 nm for the most favorable conditions. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

An equivalent dipole analysis of PZT ceramics and lead-free piezoelectric single crystals

Science.gov (United States)

Bell, Andrew J.

2016-04-01

The recently proposed Equivalent Dipole Model for describing the electromechanical properties of ionic solids in terms of 3 ions and 2 bonds has been applied to PZT ceramics and lead-free single crystal piezoelectric materials, providing analysis in terms of an effective ionic charge and the asymmetry of the interatomic force constants. For PZT it is shown that, as a function of composition across the morphotropic phase boundary, the dominant bond compliance peaks at 52% ZrO2. The stiffer of the two bonds shows little composition dependence with no anomaly at the phase boundary. The effective charge has a maximum value at 50% ZrO2, decreasing across the phase boundary region, but becoming constant in the rhombohedral phase. The single crystals confirm that both the asymmetry in the force constants and the magnitude of effective charge are equally important in determining the values of the piezoelectric charge coefficient and the electromechanical coupling coefficient. Both are apparently temperature dependent, increasing markedly on approaching the Curie temperature.

Investigation of the use of uniaxial comb-shaped Galfenol patches for a guided wave-based magnetostrictive phased array sensor

Science.gov (United States)

Yoo, Byungseok; Pines, Darryll J.

2018-05-01

This paper investigates the use of uniaxial comb-shaped Fe-Ga alloy (Galfenol) patches in the development of a Magnetostrictive Phased Array Sensor (MPAS) for the Guided Wave (GW) damage inspection technique. The MPAS consists of six highly-textured Galfenol patches with a preferred orientation and a Hexagonal Magnetic Circuit Device (HMCD). The Galfenol patches individually aligned to distinct azimuthal directions were permanently attached to a thin aluminum plate specimen. The detachable HMCD encloses a biasing magnet and six sensing coils with unique directional sensing preferences, equivalent to the specific orientation of the discrete Galfenol patches. The preliminary experimental tests validated that the GW sensing performance and directional sensitivity of the Galfenol-based sensor were significantly improved by the magnetic shape anisotropy effect on the fabrication of uniaxial comb fingers to a Galfenol disc patch. We employed a series of uniaxial comb-shaped Galfenol patches to form an MPAS with a hexagonal sensor configuration, uniformly arranged within a diameter of 1". The Galfenol MPAS was utilized to identify structural damage simulated by loosening joint bolts used to fasten the plate specimen to a frame structure. We compared the damage detection results of the MPAS with those of a PZT Phased Array Sensor (PPAS) collocated to the back surface of the plate. The directional filtering characteristic of the Galfenol MPAS led to acquiring less complicated GW signals than the PPAS using omnidirectional PZT discs. However, due to the detection limit of the standard hexagonal patterned array, the two array sensors apparently identified only the loosened bolts located along one of the preferred orientations of the array configuration. The use of the fixed number of the Galfenol patches for the MPAS construction constrained the capability of sensing point multiplication of the HMCD by altering its rotational orientation, resulting in such damage detection

Modified PZT ceramics as a material that can be used in micromechatronics

Science.gov (United States)

Zachariasz, Radosław; Bochenek, Dariusz

2015-11-01

Results on investigations of the PZT type ceramics with the following chemical composition: Pb0.94Sr0.06(Zr0.50 Ti0.50)0.99 Cr0.01O3 (PSZTC) which belongs to a group of multicomponent ceramic materials obtained on basis of the PZT type solid solution, are presented in this work. Ceramics PSZTC was obtained by a free sintering method under the following conditions: Tsint = 1250 °C and tsint = 2 h. Ceramic compacts of specimens for the sintering process were made from the ceramic mass consisting of a mixture of the synthesized PSZTC powder and 3% polyvinyl alcohol while wet. The PSZTC ceramic specimens were subjected to poling by two methods: low temperature and high temperature. On the basis of the examinations made it has been found that the ceramics obtained belongs to ferroelectric-hard materials and that is why it may be used to build resonators, filters and ultrasonic transducers. Contribution to the Topical Issue "Materials for Dielectric Applications" edited by Maciej Jaroszewski and Sabu Thomas.

Structural, dielectric and ferroelectric characterization of PZT thin films

Directory of Open Access Journals (Sweden)

Araújo E.B.

1999-01-01

Full Text Available In this work ferroelectric thin films of PZT were prepared by the oxide precursor method, deposited on Pt/Si substrate. Films of 0.5 mm average thickness were obtained. Electrical and ferroelectric characterization were carried out in these films. The measured value of the dielectric constant for films was 455. Ferroelectricity was confirmed by Capacitance-Voltage (C-V characteristics and P-E hysteresis loops. Remanent polarization for films presented value around 5.0 µC/cm2 and a coercive field of 88.8 kV/cm.

Characterization of PZT Capacitor Structures with Various Electrode Materials Processed In-Situ Using AN Automated, Rotating Elemental Target, Ion Beam Deposition System

Science.gov (United States)

Gifford, Kenneth Douglas

Ferroelectric thin film capacitor structures containing lead zirconate titanate (PZT) as the dielectric, with the chemical formula Pb(rm Zr_{x }Ti_{1-x})O_3, were synthesized in-situ with an automated ion beam sputter deposition system. Platinum (Pt), conductive ruthenium oxide (RuO_2), and two types of Pt-RuO_2 hybrid electrodes were used as the electrode materials. The capacitor structures are characterized in terms of microstructure and electrical characteristics. Reduction or elimination of non-ferroelectric phases, that nucleate during PZT processing on Pt/TiO _2/MgO and RuO_2/MgO substrates, is achieved by reducing the thickness of the individually deposited layers and by interposing a buffer layer (~100-200A) of PbTiO _3 (PT) between the bottom electrode and the PZT film. Capacitor structures containing a Pt electrode exhibit poor fatigue resistance, irregardless of the PZT microstructure or the use of a PT buffer layer. From these results, and results from similar capacitors synthesized with sol-gel and laser ablation, PZT-based capacitor structures containing Pt electrodes are considered to be unsuitable for use in memory devices. Using a PT buffer layer, in capacitor structures containing RuO_2 top and bottom electrodes and polycrystalline, highly (101) oriented PZT, reduces or eliminates the nucleation of zirconium-titanium oxide, non-ferroelectric species at the bottom electrode interface during processing. This results in good fatigue resistance up to ~2times10^ {10} switching cycles. DC leakage current density vs. time measurements follow the Curie-von Schweidler law, J(t) ~ t^ {rm -n}. Identification of the high electric field current conduction mechanism is inconclusive. The good fatigue resistance, low dc leakage current, and excellent retention, qualifies the use of these capacitor structures in non-volatile random access (NVRAM) and dynamic random access (DRAM) memory devices. Excellent fatigue resistance (10% loss in remanent polarization up to

Effect of Pb content and solution concentration of Pb{sub x}TiO{sub 3} seed layer on (100)-texture and ferroelectric/dielectric behavior of PZT (52/48) thin films

Energy Technology Data Exchange (ETDEWEB)

Zhong, Jian; Batra, Vaishali; Han, Hui; Kotru, Sushma, E-mail: skotru@eng.ua.edu [Department of Electrical and Computer Engineering, The University of Alabama, Tuscaloosa, Alabama 35487 (United States); Pandey, Raghvendar K. [Ingram School of Engineering, Texas State University, San Marcos, Texas 78666 (United States)

2015-09-15

The effect of Pb content and solution concentration of lead titanate (Pb{sub x}TiO{sub 3}) seed layer on the texture and electric properties of Pb{sub 1.1}(Zr{sub 0.52},Ti{sub 0.48})O{sub 3} (PZT) thin films was investigated. A variety of seed layers (y Pb{sub x}TiO{sub 3}) with varying solution concentration (y = 0.02, 0.05, 0.1, and 0.2 M) and Pb content (x = 1.0, 1.05, 1.1, and 1.2) was deposited on Pt/TiO{sub 2}/SiO{sub 2}/Si substrates using chemical-solution deposition method. PZT films were then deposited on these seed layers using the same process. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy investigations of the seed layers confirm change in crystal structure with variation in the solution properties. XRD studies of PZT films deposited on seed layers demonstrate that the seed layer helps in enhancing (100)-texture and suppressing (111)-texture. It was observed that PZT films prepared on seed layers with lower solution concentrations results in highly (100)-textured films, which further helps to improve the electric properties. The polarization and dielectric constant of the PZT films were seen to increase while the coercive field decreased with increase in (100)-texture. Irrespective of the seed layer solution concentration, higher Pb content in the seed layer deteriorates the PZT film properties. Ninety-five percent to ninety-six percent (100)-texture was obtained from thin PZT films deposited on seed layers of 0.02 M solution concentration with 1.05 and 1.10 Pb contents, which is higher than the values reported for thick PZT films. Optimization of both Pb content and solution concentration of the seed layer is a promising route to achieve highly (100)-textured PZT films with improved electric properties.

Determination of the Young's modulus of pulsed laser deposited epitaxial PZT thin films

NARCIS (Netherlands)

Nazeer, H.; Nguyen, Duc Minh; Woldering, L.A.; Abelmann, Leon; Rijnders, Augustinus J.H.M.; Elwenspoek, Michael Curt

2011-01-01

We determined the Young’s modulus of pulsed laser deposited epitaxially grown PbZr0.52Ti0.48O3 (PZT) thin films on microcantilevers by measuring the difference in cantilever resonance frequency before and after deposition. By carefully optimizing the accuracy of this technique, we were able to show

Influence of plasma pressure on the growth characteristics and ferroelectric properties of sputter-deposited PZT thin films

International Nuclear Information System (INIS)

Bose, A.; Maity, T.; Bysakh, S.; Seal, A.; Sen, Suchitra

2010-01-01

PZT thin films of thickness (320-1040) nm were synthesized on Si/SiO 2 /Ti/Pt multilayered substrates by radio frequency magnetron sputtering. The influence of plasma pressure in the range of (0.24-4.9) Pa, during deposition, on the structural, electrical and ferroelectric properties of the PZT films was systematically studied. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and cross-sectional transmission electron microscopy (XTEM) were employed for structural study. Nano-probe Energy Dispersive (EDX) line scanning was employed to investigate the elemental distribution across the film-bottom electrode interface. I-V characteristics and polarization-electric field (P-E) hysteresis loop of the films were measured. The study reveals that the plasma pressure has a strong influence on the evolution and texture of the ferroelectric perovskite phase and microstructure of the films. At an optimum plasma pressure of 4.1 Pa, PZT films are grown with 93% perovskite phase with (1 1 1) preferred orientation and uniform granular microstructure. These films show a saturation polarization of 67 μC/cm 2 , remnant polarization of 30 μC/cm 2 and coercive field of 28 kV/cm which, according to the literature, seem to be suitable for device applications. Transmission electron microscopy (TEM) study shows that at a plasma pressure of 4.1 Pa, the PZT/bottom Pt interface is sharp and no amorphous interlayer is formed at the interface. At a higher plasma pressure of 4.9 Pa, poor I-V and P-E hysteresis loop are observed which are interpreted as due to an amorphous interlayer at the film-bottom electrode interface which is possibly enriched in Pb, Zr, O and Pt.

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

Science.gov (United States)

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.

Electro-optic study of PZT ferroelectric ceramics using modulation of reflected light

Science.gov (United States)

Kniazkov, A. V.

2016-04-01

Electro-optic coefficients of variations in the refractive index of PZT and PLZT ceramic materials induced by ac electric field are estimated using modulation of reflected light. The electro-optic coefficients of PLZT ceramics measured with the aid of conventional birefringence using the phase shift of transmitted radiation and the proposed method of birefringence using the modulation of reflected light are compared.

Reliability of vibration energy harvesters of metal-based PZT thin films

Science.gov (United States)

Tsujiura, Y.; Suwa, E.; Kurokawa, F.; Hida, H.; Kanno, I.

2014-11-01

This paper describes the reliability of piezoelectric vibration energy harvesters (PVEHs) of Pb(Zr,Ti)O3 (PZT) thin films on metal foil cantilevers. The PZT thin films were directly deposited onto the Pt-coated stainless-steel (SS430) cantilevers by rf-magnetron sputtering, and we observed their aging behavior of power generation characteristics under the resonance vibration condition for three days. During the aging measurement, there was neither fatigue failure nor degradation of dielectric properties in our PVEHs (length: 13 mm, width: 5.0 mm, thickness: 104 μm) even under a large excitation acceleration of 25 m/s2. However, we observed clear degradation of the generated electric voltage depending on excitation acceleration. The decay rate of the output voltage was 5% from the start of the measurement at 25 m/s2. The transverse piezoelectric coefficient (e31,f) also degraded with almost the same decay rate as that of the output voltage; this indicates that the degradation of output voltage was mainly caused by that of piezoelectric properties. From the decay curves, the output powers are estimated to degrade 7% at 15 m/s2 and 36% at 25 m/s2 if we continue to excite the PVEHs for 30 years.

Reliability of vibration energy harvesters of metal-based PZT thin films

International Nuclear Information System (INIS)

Tsujiura, Y; Suwa, E; Kurokawa, F; Hida, H; Kanno, I

2014-01-01

This paper describes the reliability of piezoelectric vibration energy harvesters (PVEHs) of Pb(Zr,Ti)O 3 (PZT) thin films on metal foil cantilevers. The PZT thin films were directly deposited onto the Pt-coated stainless-steel (SS430) cantilevers by rf-magnetron sputtering, and we observed their aging behavior of power generation characteristics under the resonance vibration condition for three days. During the aging measurement, there was neither fatigue failure nor degradation of dielectric properties in our PVEHs (length: 13 mm, width: 5.0 mm, thickness: 104 μm) even under a large excitation acceleration of 25 m/s 2 . However, we observed clear degradation of the generated electric voltage depending on excitation acceleration. The decay rate of the output voltage was 5% from the start of the measurement at 25 m/s 2 . The transverse piezoelectric coefficient (e 31,f ) also degraded with almost the same decay rate as that of the output voltage; this indicates that the degradation of output voltage was mainly caused by that of piezoelectric properties. From the decay curves, the output powers are estimated to degrade 7% at 15 m/s 2 and 36% at 25 m/s 2 if we continue to excite the PVEHs for 30 years

Effect of Nd Doping on Dielectric and Impedance Properties of PZT Nanoceramics

Science.gov (United States)

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

2018-02-01

Neodymium-doped lead zirconate tianate, i.e. Pb1-x Nd x Zr0.52Ti0.48O3 (PNZT) ceramics, with x = 0-10 mol.% has been prepared by the sol-gel process. X-ray diffraction pattern at room temperature shows the pyrochlore free phase for all samples. The structural analysis suggests the coexistence of both rhombohedral (R3m space group) and tetragonal (P4 mm space group) crystal symmetries. Scanning electron micrographs of the samples show uniform distribution of grain and grain boundaries. Dielectric constant increases with the increase in neodymium concentration in the crystal lattice. Degree of diffuse phase transition increases with the increase in Nd3+ concentration in the sample. Nd3+ incorporation into the lead zirconatetitanate (PZT) lattice enhances the spreading factor. Interaction between neighbouring dipoles decreases with the increase of Nd3+ in PZT lattice. The conduction mechanism of the sample can be attributed to the overlapping large polar tunnelling. Second-order dielectric phase transition has been observed at the Curie temperature. The electrical properties of the sample can be explained by considering grain and grain boundaries contributions. All the samples show the poly-dispersive non-Debye type relaxation.

Towards a digital sound reconstruction MEMS device: Characterization of a single PZT based piezoelectric actuator

KAUST Repository

Carreno, Armando Arpys Arevalo; Conchouso Gonzalez, David; Castro, David; Jaber, Nizar; Younis, Mohammad I.; Foulds, Ian G.

2015-01-01

of acoustic actuators. These actuators consist of a flexible membrane fabricated using polyimide, which is actuated using a Lead-Zirconate-Titanate (PZT) piezoelectric ceramic layer working in the d31 actuation mode. The dimensions of the membrane are of 1mm

An equivalent dipole analysis of PZT ceramics and lead-free piezoelectric single crystals

Directory of Open Access Journals (Sweden)

Andrew J. Bell

2016-06-01

Full Text Available The recently proposed Equivalent Dipole Model for describing the electromechanical properties of ionic solids in terms of 3 ions and 2 bonds has been applied to PZT ceramics and lead-free single crystal piezoelectric materials, providing analysis in terms of an effective ionic charge and the asymmetry of the interatomic force constants. For PZT it is shown that, as a function of composition across the morphotropic phase boundary, the dominant bond compliance peaks at 52% ZrO2. The stiffer of the two bonds shows little composition dependence with no anomaly at the phase boundary. The effective charge has a maximum value at 50% ZrO2, decreasing across the phase boundary region, but becoming constant in the rhombohedral phase. The single crystals confirm that both the asymmetry in the force constants and the magnitude of effective charge are equally important in determining the values of the piezoelectric charge coefficient and the electromechanical coupling coefficient. Both are apparently temperature dependent, increasing markedly on approaching the Curie temperature.

Impedance spectroscopy of PZT ceramics--measuring diffusion coefficients, mixed conduction, and Pb loss.

Science.gov (United States)

Donnelly, Niall J; Randall, Clive A

2012-09-01

Sintering of lead zirconate titanate (PZT) at high temperatures results in loss of Pb unless an ambient Pb activity is maintained. The tell-tale sign of Pb loss is an increased conductivity, usually manifested in unacceptably high values of tanδ. The conductivity is caused by oxygen vacancies and/or electron holes which are a byproduct of Pb evaporation. In the first part of this paper, it is shown how impedance spectroscopy can be used to separate ionic and electronic conductivity in a properly designed sample by selection of appropriate boundary conditions. Subsequently, impedance is used to probe defect concentrations in PZT during prolonged annealing at 700°C. It is found that oxygen vacancies are generated during annealing in air but the rate of generation actually decreases upon lowering the ambient pO(2). These results are explained by a model of Pb evaporation which, in this case, leads predominantly to oxygen vacancy generation. In principle, this effect could be used to generate a specific vacancy concentration in similar Pb-based oxides.

Evolution of a MEMS Photoacoustic Chemical Sensor

National Research Council Canada - National Science Library

Pellegrino, Paul M; Polcawich, Ronald G

2003-01-01

.... Initial MEMS work is centered on fabrication of a lead zirconate titanate (PZT) microphone subsystem to be incorporated in the full photoacoustic device. Preliminary results were very positive for the macro-photoacoustic cell, PZT membrane microphones design / fabrication and elementary monolithic MEMS photoacoustic cavity.

Imprint behavior of piezoelectric PZT thin films deposited onto Cu-coated polymer substrates

Czech Academy of Sciences Publication Activity Database

Suchaneck, G.; Hubička, Zdeněk; Čada, Martin; Kiselev, D.A.; Bdikin, I.; Levin, A.A.; Jastrabík, Lubomír; Kholkin, A. L.; Gerlach, G.; Dejneka, Alexandr

2011-01-01

Roč. 419, č. 1 (2011), s. 103-108 ISSN 0015-0193 R&D Projects: GA ČR GC202/09/J017; GA AV ČR KAN301370701 Institutional research plan: CEZ:AV0Z10100522 Keywords : plasma deposition * PZT * imprint * piezoresponse force microscopy Subject RIV: BH - Optics, Masers, Lasers Impact factor: 0.391, year: 2011

Using the methods of radiospectroscopy (EPR, NMR) to study the nature of the defect structure of solid solutions based on lead zirconate titanate (PZT).

Science.gov (United States)

Bykov, Igor; Zagorodniy, Yuriy; Yurchenko, Lesya; Korduban, Alexander; Nejezchleb, Karel; Trachevsky, Vladimir; Dimza, Vilnis; Jastrabik, Lubomir; Dejneka, Alexander

2014-08-01

The nature of intrinsic and impurity point defects in lead zirconate titanate (PZT) ceramics has been explored. Using electron paramagnetic resonance (EPR), nuclear magnetic resonance (NMR), and X-ray photoelectron spectroscopy (XPS) methods, several impurity sites have been identified in the materials, including the Fe(3+)-oxygen vacancy (VO) complex and Pb ions. Both of these centers are incorporated into the PZT lattice. The Fe(3+) –VО paramagnetic complex serves as a sensitive probe of the local crystal field in the ceramic; the symmetry of this defect roughly correlates with PZT phase diagram as the composition is varied from PbTiO3 to PbZrO3. NMR spectra (207)Pb in PbTiO3, PbZrO3, and PZT with iron content from 0 to 0.4 wt% showed that increasing the iron concentration leads to a distortion of the crystal structure and to improvement of the electrophysical parameters of the piezoceramics. This is due to the formation of a phase which has a higher symmetry, but at high concentrations of iron (>0.4 wt%), it leads to sharp degradation of electrophysical parameters.

The thickness effect of Bi3.25La0.75Ti3O12 buffer layer in PbZr0.58Ti0.42O3/Bi3.25La0.75Ti3O12 (PZT/BLT) multilayered ferroelectric thin films

International Nuclear Information System (INIS)

Li Jianjun; Li Ping; Zhang Guojun; Yu Jun; Wu Yunyi; Wen Xinyi

2011-01-01

A series of PbZr 0.58 Ti 0.42 O 3 (PZT) thin films with various Bi 3.25 La 0.75 Ti 3 O 12 (BLT) buffer layer thicknesses were deposited on Pt/TiO 2 /SiO 2 /p-Si(100) substrates by RF magnetron sputtering. The X-ray diffraction measurements of PZT film and PZT/BLT multilayered films illustrate that the pure PZT film shows (111) preferential orientation, and the PZT/BLT films show (110) preferential orientation with increasing thickness of the BLT layer. There are no obvious diffraction peaks for the BLT buffer layer in the multilayered films, for interaction effect between the bottom BLT and top PZT films during annealing at the same time. From the surface images of field-emission scanning electron microscope, there are the maximum number of largest-size grains in PZT/BLT(30 nm) film among all the samples. The growth direction and grain size have significant effects on ferroelectric properties of the multilayered films. The fatigue characteristics of PZT and PZT/BLT films suggest that 30-nm-thick BLT is just an effective buffer layer enough to alleviate the accumulation of oxygen vacancies near the PZT/BLT interface. The comparison of these results with that of PZT/Pt/TiO 2 /SiO 2 /p-Si(100) basic structured film suggests that the buffer layer with an appropriate thickness can improve the ferroelectric properties of multilayered films greatly.

Impact of process parameters on the structural and electrical properties of metal/PZT/Al2O3/silicon gate stack for non-volatile memory applications

Science.gov (United States)

Singh, Prashant; Jha, Rajesh Kumar; Singh, Rajat Kumar; Singh, B. R.

2018-02-01

In this paper, we present the structural and electrical properties of the Al2O3 buffer layer on non-volatile memory behavior using Metal/PZT/Al2O3/Silicon structures. Metal/PZT/Silicon and Metal/Al2O3/Silicon structures were also fabricated and characterized to obtain capacitance and leakage current parameters. Lead zirconate titanate (PZT::35:65) and Al2O3 films were deposited by sputtering on the silicon substrate. Memory window, PUND, endurance, breakdown voltage, effective charges, flat-band voltage and leakage current density parameters were measured and the effects of process parameters on the structural and electrical characteristics were investigated. X-ray data show dominant (110) tetragonal phase of the PZT film, which crystallizes at 500 °C. The sputtered Al2O3 film annealed at different temperatures show dominant (312) orientation and amorphous nature at 425 °C. Multiple angle laser ellipsometric analysis reveals the temperature dependence of PZT film refractive index and extinction coefficient. Electrical characterization shows the maximum memory window of 3.9 V and breakdown voltage of 25 V for the Metal/Ferroelectric/Silicon (MFeS) structures annealed at 500 °C. With 10 nm Al2O3 layer in the Metal/Ferroelectric/Insulator/Silicon (MFeIS) structure, the memory window and breakdown voltage was improved to 7.21 and 35 V, respectively. Such structures show high endurance with no significant reduction polarization charge for upto 2.2 × 109 iteration cycles.

Extrinsic Fabry-Perot ultrasonic detector

Science.gov (United States)

Kidwell, J. J.; Berthold, John W., III

1996-10-01

We characterized the performance of a commercial fiber optic extrinsic Fabry-Perot interferometer for use as an ultrasonic sensor, and compared the performance with a standard lead zirconate titanate (PZT) detector. The interferometer was unstabilized. The results showed that the fiber sensor was about 12 times less sensitive than the PZT detector. Ultrasonic frequency response near 100 kHz was demonstrated. We describe the design of the fiber sensor, the details of the tests performed, and potential applications.

Homogeneity Analysis of a MEMS-based PZT Thick Film Vibration Energy Harvester Manufacturing Process

DEFF Research Database (Denmark)

Lei, Anders; Xu, Ruichao; Borregaard, Louise M.

2012-01-01

This paper presents a homogeneity analysis of a high yield wafer scale fabrication of MEMS-based unimorph silicon/PZT thick film vibration energy harvesters aimed towards vibration sources with peak vibrations in the range of around 300Hz. A wafer with a yield of 91% (41/45 devices) has been...

Síntese e caracterização da cerâmica PZT dopada com íons bário Synthesis and characterization of barium-doped PZT ceramics

Directory of Open Access Journals (Sweden)

G. Gasparotto

2003-04-01

Full Text Available Pós de titanato zirconato de chumbo (PZT puros e dopados com bário foram obtidos pelo método de precursores poliméricos, conformados uniaxialmente, na forma de cilindros, utilizando 15 MPa, e prensados isostaticamente à 210MPa. Com o objetivo de estudar o comportamento de sinterização os compactos foram divididos em dois lotes. Sendo um sinterizado em um forno acoplado a um dilatômetro até a temperatura de 1300 °C e o outro sinterizado em forno tipo mufla, em sistema fechado, na temperatura de 1100 °C por 4 horas. Verificou-se que a adição do íon bário influencia na cinética de sinterização, na densificação final, na microestrutura e nas propriedades elétricas da cerâmica. A adição de bário aumenta a concentração da fase tetragonal no PZT, em função da substituição do chumbo por bário na rede perovskita. As amostras dopadas com concentrações maiores que 5,0 mol % em bário apresentaram segregação de PbO no contorno de grão, inibindo seu crescimento.Pure and barium doped lead zirconate titanate powders were obtained by the polymeric precursor method, uniaxially conformed in cylinders form using 15 MPa and pressing isostatically at 210 MPa. In order to study the sintering behaviour, the compacts were divided in two parts. One part was sintered in a dilatometer furnace till 1300 °C and the other one sintered in muffle furnace in the temperature of 1100 °C for 4 hours. It was verified that the addition of barium influences on the sintering kinetics, on the final density, microstructure and electric properties of the ceramics. The addition of barium increases the concentration of the tetragonal phase of PZT due to the substitution of lead by barium in the perovskite lattice. The samples doped with barium concentrations higher than 5.0 mol % leads to the segregation of PbO in the grain boundary, inhibiting grain growth.

Concrete Infill Monitoring in Concrete-Filled FRP Tubes Using a PZT-Based Ultrasonic Time-of-Flight Method.

Science.gov (United States)

Luo, Mingzhang; Li, Weijie; Hei, Chuang; Song, Gangbing

2016-12-07

Concrete-filled fiber-reinforced polymer tubes (CFFTs) have attracted interest for their structural applications in corrosive environments. However, a weak interfacial strength between the fiber-reinforced polymer (FRP) tube and the concrete infill may develop due to concrete shrinkage and inadequate concrete compaction during concrete casting, which will destroy the confinement effect and thereby reduce the load bearing capacity of a CFFT. In this paper, the lead zirconate titanate (PZT)-based ultrasonic time-of-flight (TOF) method was adopted to assess the concrete infill condition of CFFTs. The basic idea of this method is that the velocity of the ultrasonic wave propagation in the FRP material is about half of that in concrete material. Any voids or debonding created along the interface between the FRP tube and the concrete will delay the arrival time between the pairs of PZT transducers. A comparison of the arrival times of the PZT pairs between the intact and the defected CFFT was made to assess the severity of the voids or the debonding. The feasibility of the methodology was analyzed using a finite-difference time-domain-based numerical simulation. Experiments were setup to validate the numerical results, which showed good agreement with the numerical findings. The results showed that the ultrasonic time-of-flight method is able to detect the concrete infill condition of CFFTs.

Concrete Infill Monitoring in Concrete-Filled FRP Tubes Using a PZT-Based Ultrasonic Time-of-Flight Method

Science.gov (United States)

Luo, Mingzhang; Li, Weijie; Hei, Chuang; Song, Gangbing

2016-01-01

Concrete-filled fiber-reinforced polymer tubes (CFFTs) have attracted interest for their structural applications in corrosive environments. However, a weak interfacial strength between the fiber-reinforced polymer (FRP) tube and the concrete infill may develop due to concrete shrinkage and inadequate concrete compaction during concrete casting, which will destroy the confinement effect and thereby reduce the load bearing capacity of a CFFT. In this paper, the lead zirconate titanate (PZT)-based ultrasonic time-of-flight (TOF) method was adopted to assess the concrete infill condition of CFFTs. The basic idea of this method is that the velocity of the ultrasonic wave propagation in the FRP material is about half of that in concrete material. Any voids or debonding created along the interface between the FRP tube and the concrete will delay the arrival time between the pairs of PZT transducers. A comparison of the arrival times of the PZT pairs between the intact and the defected CFFT was made to assess the severity of the voids or the debonding. The feasibility of the methodology was analyzed using a finite-difference time-domain-based numerical simulation. Experiments were setup to validate the numerical results, which showed good agreement with the numerical findings. The results showed that the ultrasonic time-of-flight method is able to detect the concrete infill condition of CFFTs. PMID:27941617

Soft pneumatic actuator skin with piezoelectric sensors for vibrotactile feedback

Directory of Open Access Journals (Sweden)

Harshal Arun Sonar

2016-01-01

Full Text Available The latest wearable technologies demand more intuitive and sophisticated interfaces for communication, sensing, and feedback closer to the body. Evidently, such interfaces require flexibility and conformity without losing their functionality even on rigid surfaces. Although there has been various research efforts in creating tactile feedback to improve various haptic interfaces and master-slave manipulators, we are yet to see a comprehensive device that can both supply vibratory actuation and tactile sensing. This paper describes a soft pneumatic actuator (SPA based, SPA-skin prototype that allows bidirectional tactile information transfer to facilitate simpler and responsive wearable interface. We describe the design and fabrication of a 1.4 mm-thick vibratory SPA - skin that is integrated with piezoelectric sensors. We examine in detail the mechanical performance compared to the SPA model and the sensitivity of the sensors for the application in vibrotactile feedback. Experimental findings show that this ultra-thin SPA and the unique integration process of the discrete lead zirconate titanate (PZT based piezoelectric sensors achieve high resolution of soft contact sensing as well as accurate control on vibrotactile feedback by closing the control loop.

Fatigue response of a PZT multilayer actuator under high-field electric cycling with mechanical preload

Science.gov (United States)

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

2009-01-01

An electric fatigue test system was developed for evaluating the reliability of piezoelectric actuators with a mechanical loading capability. Fatigue responses of a lead zirconate titanate (PZT) multilayer actuator with a platethrough electrode configuration were studied under an electric field (1.7 times that of the coercive field of PZT material) and a concurrent mechanical preload (30.0 MPa). A total of 109 cycles was carried out. Variations in charge density and mechanical strain under the 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 using fast Fourier transformation. Both the dielectric and the piezoelectric coefficients exhibited a monotonic decrease prior to 2.86×108 cycles under certain preloading conditions, and then fluctuated. Both the dielectric loss tangent and the piezoelectric loss tangent also fluctuated after a decrease. The results are interpreted and discussed with respect to domain wall activities, microdefects, and other anomalies.

Realization of face-shear piezoelectric coefficient d36 in PZT ceramics via ferroelastic domain engineering

Science.gov (United States)

Miao, Hongchen; Li, Faxin

2015-09-01

The piezoelectric face-shear ( d36 ) mode may be the most useful shear mode in piezoelectrics, while currently this mode can only exist in single crystals of specific point groups and cut directions. Theoretically, the d36 coefficient vanishes in piezoelectric ceramics because of its transversally isotropic symmetry. In this work, we modified the symmetry of poled PZT ceramics from transversally isotropic to orthogonal through ferroelastic domain switching by applying a high lateral stress along the "2" direction and holding the stress for several hours. After removing the compression, the piezoelectric coefficient d31 is found much larger than d32 . Then, by cutting the compressed sample along the Z x t ±45 ° direction, we realized d36 coefficients up to 206 pC/N , which is measured by using a modified d33 meter. The obtained large d36 coefficients in PZT ceramics could be very promising for face-shear mode resonators and shear horizontal wave generation in nondestructive testing.

Shear piezoelectric coefficients of PZT, LiNbO3 and PMN-PT at cryogenic temperatures

International Nuclear Information System (INIS)

Bukhari, Syed; Islam, Md; Haziot, Ariel; Beamish, John

2014-01-01

Piezoelectric transducers are used to detect stress and to generate nanometer scale displacements but their piezoelectric coefficients decrease with temperature, limiting their performance in cryogenic applications. We have developed a capacitive technique and directly measured the temperature dependence of the shear coefficient d 15 for ceramic lead zirconium titanate (PZT), 41° X-cut lithium niobate (LiNbO 3 ) and single crystal lead magnesium niobium-lead titanate (PMN-PT). In PZT, d 15 decreases nearly linearly with temperature, dropping by factor of about 4 by 1.3 K. LiNbO3 has the smallest room temperature d15, but its value decreased by only 6% at the lowest temperatures. PMN-PT had the largest value of d15 at room temperature (2.9 × 10 −9 m/V, about 45 times larger than for LiNbO 3 ) but it decreased rapidly below 75 K; at 1.3 K, d 15 was only about 8% of its room temperature value

Enhanced tunability of magneto-impedance and magneto-capacitance in annealed Metglas/PZT magnetoelectric composites

Science.gov (United States)

Leung, Chung Ming; Zhuang, Xin; Xu, Junran; Li, Jiefang; Zhang, Jitao; Srinivasan, G.; Viehland, D.

2018-05-01

This report is on a new class of magnetostatically tunable magneto-impedance and magneto-capacitance devices based on a composite of ferromagnetic Metglas and ferroelectric lead zirconate titanate (PZT). Layered magneto-electric (ME) composites with annealed Metglas and PZT were studied in a longitudinal in-plane magnetic field-transverse electric field (L-T) mode. It was found that the degree of tunability was dependent on the annealing temperature of Metglas. An impedance tunability (ΔZ/Z0) of ≥400% was obtained at the electromechanical resonance (EMR) frequency (fr) for a sample with Metglas layers annealed at Ta = 500oC. This tunability is a factor of two higher than for composites with Metglas annealed at 350oC. The tunability of the capacitance, (ΔC/C0), was found to be 290% and -135k% at resonance and antiresonance, respectively, for Ta = 500oC. These results provide clear evidence for improvement in static magnetic field tunability of impedance and capacitance of ME composites with the use of annealed Metglas and are of importance for their potential use in tunable electronic applications.

Deposition of highly (111)-oriented PZT thin films by using metal organic chemical deposition

CERN Document Server

Bu, K H; Choi, D K; Seong, W K; Kim, J D

1999-01-01

Lead zirconate titanate (PZT) thin films have been grown on Pt/Ta/SiNx/Si substrates by using metal organic chemical vapor deposition with Pb(C sub 2 H sub 5) sub 4 , Zr(O-t-C sub 4 H sub 9) sub 4 , and Ti(O-i-C sub 3 H sub 7) sub 4 as source materials and O sub 2 as an oxidizing gas. The Zr fraction in the thin films was controlled by varying the flow rate of the Zr source material. The crystal structure and the electrical properties were investigated as functions of the composition. X-ray diffraction analysis showed that at a certain range of Zr fraction, highly (111)-oriented PZT thin films with no pyrochlore phases were deposited. On the other hand, at low Zr fractions, there were peaks from Pb-oxide phases. At high Zr fractions, peaks from pyrochlore phase were seen. The films also showed good electrical properties, such as a high dielectric constant of more than 1200 and a low coercive voltage of 1.35 V.

A 2-D MEMS scanning mirror based on dynamic mixed mode excitation of a piezoelectric PZT thin film S-shaped actuator.

Science.gov (United States)

Koh, Kah How; Kobayashi, Takeshi; Lee, Chengkuo

2011-07-18

A novel dynamic excitation of an S-shaped PZT piezoelectric actuator, which is conceptualized by having two superimposed AC voltages, is characterized in this paper through the evaluation of the 2-D scanning characteristics of an integrated silicon micromirror. The device is micromachined from a SOI wafer with a 5 μm thick Si device layer and multilayers of Pt/Ti/PZT//Pt/Ti deposited as electrode and actuation materials. A large mirror (1.65 mm x 2mm) and an S-shaped PZT actuator are formed after the backside release process. Three modes of operation are investigated: bending, torsional and mixed. The resonant frequencies obtained for bending and torsional modes are 27Hz and 70Hz respectively. The maximum measured optical deflection angles obtained at 3Vpp are ± 38.9° and ± 2.1° respectively for bending and torsional modes. Various 2-D Lissajous patterns are demonstrated by superimposing two ac sinusoidal electrical signals of different frequencies (27 Hz and 70 Hz) into one signal to be used to actuate the mirror.

Integrated dynamic and static tactile sensor: focus on static force sensing

Science.gov (United States)

Wettels, Nicholas; Pletner, Baruch

2012-04-01

Object grasping by robotic hands in unstructured environments demands a sensor that is durable, compliant, and responsive to static and dynamic force conditions. In order for a tactile sensor to be useful for grasp control in these, it should have the following properties: tri-axial force sensing (two shear plus normal component), dynamic event sensing across slip frequencies, compliant surface for grip, wide dynamic range (depending on application), insensitivity to environmental conditions, ability to withstand abuse and good sensing behavior (e.g. low hysteresis, high repeatability). These features can be combined in a novel multimodal tactile sensor. This sensor combines commercial-off-the-shelf MEMS technology with two proprietary force sensors: a high bandwidth device based on PZT technology and low bandwidth device based on elastomers and optics. In this study, we focus on the latter transduction mechanism and the proposed architecture of the completed device. In this study, an embedded LED was utilized to produce a constant light source throughout a layer of silicon rubber which covered a plastic mandrel containing a set of sensitive phototransistors. Features about the contacted object such as center of pressure and force vectors can be extracted from the information in the changing patterns of light. The voltage versus force relationship obtained with this molded humanlike finger had a wide dynamic range that coincided with forces relevant for most human grip tasks.

Ferroelectricity, Piezoelectricity, and Dielectricity of 0.06PMnN-0.94PZT(45/55 Thin Film on Silicon Substrate

Directory of Open Access Journals (Sweden)

Tao Zhang

2015-01-01

Full Text Available The high piezoelectricity and high quality factor ferroelectric thin films are important for electromechanical applications especially the micro electromechanical system (MEMS. The ternary compound ferroelectric thin films 0.06Pb(Mn1/3, Nb2/3O3 + 0.94Pb(Zr0.45, Ti0.55O3 (0.06PMnN-0.94PZT(45/55 were deposited on silicon(100 substrates by RF magnetron sputtering method considering that Mn and Nb doping will improve PZT properties in this research. For comparison, nondoped PZT(45/55 films were also deposited. The results show that both of thin films show polycrystal structures with the main (111 and (101 orientations. The transverse piezoelectric coefficients are e31,eff=−4.03 C/m2 and e31,eff=-3.5 C/m2, respectively. These thin films exhibit classical ferroelectricity, in which the coercive electric field intensities are 2Ec=147.31 kV/cm and 2Ec=135.44 kV/cm, and the saturation polarization Ps=30.86 μC/cm2 and Ps=17.74 μC/cm2, and the remnant polarization Pr=20.44 μC/cm2 and Pr=9.87 μC/cm2, respectively. Moreover, the dielectric constants and loss are εr=681 and D=5% and εr=537 and D=4.3%, respectively. In conclusion, 0.06PMnN-0.94PZT(45/55 thin films act better than nondoped films, even though their dielectric constants are higher. Their excellent ferroelectricity, piezoelectricity, and high power and energy storage property, especially the easy fabrication, integration realizable, and potentially high quality factor, make this kind of thin films available for the realistic applications.

Thick Films acoustic sensors devoted to MTR environment measurements. Thick Films acoustic sensors devoted to Material Testing Reactor environment measurements

International Nuclear Information System (INIS)

Very, F.; Rosenkrantz, E.; Combette, P.; Ferrandis, J.Y.; Fourmentel, D.; Destouches, C.; Villard, J.F.

2015-01-01

The development of advanced instrumentation for in-pile experiments in Material Testing Reactor constitutes a main goal for the improvement of the nuclear fuel behavior knowledge. An acoustic method for fission gas release detection was tested with success during a first experiment called REMORA 3 in 2010 and 2011, and the results were used to differentiate helium and fission gas release kinetics under transient operating conditions. This experiment was lead at OSIRIS reactor (CEA Saclay, France). The maximal temperature on the sensor during the irradiation was about 150 deg. C. In this paper we present a thick film transducer produce by screen printing process. The screen printing of piezoelectric offers a wide range of possible applications for the development of acoustic sensors and piezoelectric structure for measurements in high temperature environment. We firstly produced a Lead Zirconate Titanate (PZT) based paste composed of Pz27 powder from Ferroperm, CF7575 glass, and organic solvent ESL 400. Likewise a Bismuth Titanate based paste synthesized in our laboratory was produced. With these inks we produced thick film up to 130 μm by screen printing process. Material properties characterizations of these thick-film resonators are essential for device design and applications. The piezoelectric coefficients d33 and pyro-electric P(T) coefficient are investigated. The highest P(T) and d33 are respectively 80 μC.m -2 .K -1 and 130 μC.N -1 for the PZT transducer -which validates the fabrication process-. In view of the development of this transducer oriented for high temperature and irradiation environment, we investigated the electrical properties of the transducers for different ranges of frequencies and temperature - from 20 Hz up to 40 MHz between 30 and 400 deg. C. We highlight the evolution of the impedance response and piezoelectric parameters of screen printed piezoelectric structures on alumina. Shortly an irradiation will be realized in order to

Thick Films acoustic sensors devoted to MTR environment measurements. Thick Films acoustic sensors devoted to Material Testing Reactor environment measurements

Energy Technology Data Exchange (ETDEWEB)

Very, F.; Rosenkrantz, E.; Combette, P.; Ferrandis, J.Y. [University Montpellier, IES, UMR 5214, F-34000, Montpellier (France); CNRS, IES, UMR 5214, F-34000, Montpellier (France); Fourmentel, D.; Destouches, C.; Villard, J.F. [CEA, DEN, Instrumentation Sensors and Dosimetry Laboratory, Cadarache, F-13108 St Paul lez Durance (France)

2015-07-01

The development of advanced instrumentation for in-pile experiments in Material Testing Reactor constitutes a main goal for the improvement of the nuclear fuel behavior knowledge. An acoustic method for fission gas release detection was tested with success during a first experiment called REMORA 3 in 2010 and 2011, and the results were used to differentiate helium and fission gas release kinetics under transient operating conditions. This experiment was lead at OSIRIS reactor (CEA Saclay, France). The maximal temperature on the sensor during the irradiation was about 150 deg. C. In this paper we present a thick film transducer produce by screen printing process. The screen printing of piezoelectric offers a wide range of possible applications for the development of acoustic sensors and piezoelectric structure for measurements in high temperature environment. We firstly produced a Lead Zirconate Titanate (PZT) based paste composed of Pz27 powder from Ferroperm, CF7575 glass, and organic solvent ESL 400. Likewise a Bismuth Titanate based paste synthesized in our laboratory was produced. With these inks we produced thick film up to 130 μm by screen printing process. Material properties characterizations of these thick-film resonators are essential for device design and applications. The piezoelectric coefficients d33 and pyro-electric P(T) coefficient are investigated. The highest P(T) and d33 are respectively 80 μC.m{sup -2}.K{sup -1} and 130 μC.N{sup -1} for the PZT transducer -which validates the fabrication process-. In view of the development of this transducer oriented for high temperature and irradiation environment, we investigated the electrical properties of the transducers for different ranges of frequencies and temperature - from 20 Hz up to 40 MHz between 30 and 400 deg. C. We highlight the evolution of the impedance response and piezoelectric parameters of screen printed piezoelectric structures on alumina. Shortly an irradiation will be realized in

Electrical and ferroelectric properties of RF sputtered PZT/SBN on silicon for non-volatile memory applications

Science.gov (United States)

Singh, Prashant; Jha, Rajesh Kumar; Singh, Rajat Kumar; Singh, B. R.

2018-02-01

We report the integration of multilayer ferroelectric film deposited by RF magnetron sputtering and explore the electrical characteristics for its application as the gate of ferroelectric field effect transistor for non-volatile memories. PZT (Pb[Zr0.35Ti0.65]O3) and SBN (SrBi2Nb2O9) ferroelectric materials were selected for the stack fabrication due to their large polarization and fatigue free properties respectively. Electrical characterization has been carried out to obtain memory window, leakage current density, PUND and endurance characteristics. Fabricated multilayer ferroelectric film capacitor structure shows large memory window of 17.73 V and leakage current density of the order 10-6 A cm-2 for the voltage sweep of -30 to +30 V. This multilayer gate stack of PZT/SBN shows promising endurance property with no degradation in the remnant polarization for the read/write iteration cycles upto 108.

Characterization of Kerfless Linear Arrays Based on PZT Thick Film.

Science.gov (United States)

Zawada, Tomasz; Bierregaard, Louise Moller; Ringgaard, Erling; Xu, Ruichao; Guizzetti, Michele; Levassort, Franck; Certon, Dominique

2017-09-01

Multielement transducers enabling novel cost-effective fabrication of imaging arrays for medical applications have been presented earlier. Due to the favorable low lateral coupling of the screen-printed PZT, the elements can be defined by the top electrode pattern only, leading to a kerfless design with low crosstalk between the elements. The thick-film-based linear arrays have proved to be compatible with a commercial ultrasonic scanner and to support linear array beamforming as well as phased array beamforming. The main objective of the presented work is to investigate the performance of the devices at the transducer level by extensive measurements of the test structures. The arrays have been characterized by several different measurement techniques. First, electrical impedance measurements on several elements in air and liquid have been conducted in order to support material parameter identification using the Krimholtz-Leedom-Matthaei model. It has been found that electromechanical coupling is at the level of 35%. The arrays have also been characterized by a pulse-echo system. The measured sensitivity is around -60 dB, and the fractional bandwidth is close to 60%, while the center frequency is about 12 MHz over the whole array. Finally, laser interferometry measurements have been conducted indicating very good displacement level as well as pressure. The in-depth characterization of the array structure has given insight into the performance parameters for the array based on PZT thick film, and the obtained information will be used to optimize the key parameters for the next generation of cost-effective arrays based on piezoelectric thick film.

Direct piezoelectric effect d33 non-linearity in PZT ceramics

OpenAIRE

Pérez Pérez, Rafael; Albareda Tiana, Alfonso; Pérez Codina, Estel; García García, José Eduardo; Tiana Alsina, Jordi; Gorri Ochoa, José Antonio

2006-01-01

Se ha implementado una nueva técnica de medida aplicando un esfuerzo uniaxial sobre la muestra y midiendo la carga generada. Se aplica un esfuerzo suficientemente intenso para producir efectos no lineales, y se analiza la respuesta no sólo en función de la amplitud del esfuerzo sino de su valor instantáneo. Se ha observado que el coeficiente d33 aumenta siempre linealmente con la amplitud, tanto en las cerámicas PZT comerciales blandas como en las duras, en este último caso al revés de lo qu...

No linealidad del efecto piezoelectrico directo d33 en cerámicas PZT

Directory of Open Access Journals (Sweden)

Gorri, J. A.

2006-06-01

Full Text Available A new measurement method has been developed in order to analyse the non-linear behaviour of piezoelectric ceramics. Based on Berlincourt–type method, the applied stress is so high that non linear effects can be produced. Its response is analysed not only in terms of the stress amplitude but also in terms of the instantaneous value. The treatment is similar to that we have applied to the dielectric response. Previously, the dependence on the pre-stress strength has been determined, and also the influence of the time elapsed since its application. A decrease in d33 is observed when pre-stress TB rises. Piezoelectric coefficient d33 increases linearly with the amplitude, not only in soft but also in hard PZT ceramics, opposite to the dielectric behaviour. The rate between real and imaginary part of the coefficient d33 is equal to the expected value in soft PZT, but it is not so in hard one. Since in the dielectric case hard PZT shows a strong and positive dependence with the applied instantaneous field, in that case the dependence is very light. This study is complemented by the dependence of the dielectric constant non-linearities with the applied pre-stress.Se ha implementado una nueva técnica de medida para la determinación del comportamiento no lineal de las cerámicas piezoeléctricas. Es una medida tipo Berlincourt, en la que se aplica un esfuerzo suficientemente intenso para producir efectos no lineales, y se analiza la respuesta no sólo en función de la amplitud del esfuerzo sino de su valor instantáneo. Con ello se realiza un tratamiento similar al realizado anteriormente en la medida de la constante dieléctrica. Previamente, se ha determinado la dependencia con el pre-esfuerzo aplicado y con el tiempo transcurrido desde su aplicación. Se observa el decrecimiento de d33 al aumentar el pre-esfuerzo TB. Se ha observado que el coeficiente d33 aumenta siempre linealmente con la amplitud, tanto en las cerámicas PZT comerciales blandas

Improvement in ferroelectric properties of Pt/PZT/Pt capacitors etched as a function of Ar/O2 gas mixing ratio into Cl2/CF4 plasma

International Nuclear Information System (INIS)

Lim, Kyu-Tae; Koo, Seong-Mo; Kim, Kyoung-Tae; Kim, Dong-Pyo; Kim, Chang-Il

2004-01-01

In this work, to investigate improvement of the damage using oxygen containing plasma, we etched PZT films as a function of Ar (x%)/O 2 (y%) gas mixing ratio in Cl 2 (56%)/CF 4 (14%) plasma (where the sum of x and y is 30). The maximum etch rate of the PZT thin films was 146 nm/min for Ar (30%)/O 2 (0%) added into the Cl 2 /CF 4 plasma. After the etching, the plasma-induced damages were characterized in terms of hysteresis curves, leakage current, switching polarization and retention capacity as a function of the gas mixing ratio. When the ferroelectric properties of PZT films were etched as a function of O 2 and Ar and the gas mixing ratios were compared, the value of remnant polarization in O 2 (30%) added Cl 2 /CF 4 plasma is higher than that in Ar (30%). The results showed that after the etching the charges accumulated by oxygen vacancies prevented further domain switching at the top electrode-ferroelectric interface and created leakage current because of modification of the interfacial Schottky barrier during the etching process. The physical damage to the near surface and the crystal structure of the etched PZT thin films was evaluated by using X-ray diffraction (XRD). The remnant polarization, leakage current, retention and fatigue properties are improved with increasing O 2 content. From XRD results, the improvement in the ferroelectric properties of PZT capacitors etched in O 2 containing plasma was consistent with the increased intensities of the (100) and (200) peaks

Hot-Spot Fatigue and Impact Damage Detection on a Helicopter Tailboom

Science.gov (United States)

2011-09-01

other 14 PZT disks were used as sensors. Among the 28 PZT disks, 16 PZT disks were placed in the two fatigue hot-spot areas to detect cracks initiated...more efficient and effective airframe maintenance, fatigue cracking and impact damage detection technologies were developed and demonstrated on a...SHM system in successfully monitoring fatigue cracks initiated from cyclical loading conditions; detecting, locating and quantifying ballistic

A Multidisciplinary Approach to Health Monitoring and Materials Damage Prognosis for Metallic Aerospace Systems

Science.gov (United States)

2013-03-01

50 signals were used from Figure 24. Fatigue damage classification in an aluminum lug joint specimen using PZT sensor data without and with...modeling, the single fatigue crack is assumed to be non-breathing during the deformation of the beam. The surface-bonded piezoceramic ( PZT ) actuator...25. Beam with a single fatigue crack under PZT actuation and temperature variations. 20 beam through material expansionis negligible compared

Physical properties of inorganic PMW-PNN-PZT ceramics

Science.gov (United States)

Sin, Sang-Hoon; Yoo, Ju-hyun; Kim, Yong-Jin; Baek, Sam-ki; Ha, Jun-Soo; No, Chung-Han; Song, Hyun-Seon; Shin, Dong-Chan

2015-07-01

In this work, inorganic Pb(Mg1/2W1/2)0.03(Ni1/3Nb2/3)x(Zr0.5Ti0.5)0.97-xO3 (x = 0.02 ∼ 0.12) composition ceramics were fabricated by the conventional solid state reaction method. And then their micro structure and ferroelectric properties were investigated according to the amount of PNN substitution. Small amounts of Li2CO3 and CaCO3 were used in order to decrease the sintering temperature of the ceramics. The 0.10 mol PNN-substituted PMW-PNN- PZT ceramics sintered at 920°C showed the excellent physical properties of piezoelectric constant (d33), electromechanical coupling factor (kp), mechanical quality coefficient (Qm), and dielectric constant of 566 pC/N, 0.61, 73, and 2183, respectively.

Use of Savitzky-Golay Filter for Performances Improvement of SHM Systems Based on Neural Networks and Distributed PZT Sensors.

Science.gov (United States)

de Oliveira, Mario A; Araujo, Nelcileno V S; da Silva, Rodolfo N; da Silva, Tony I; Epaarachchi, Jayantha

2018-01-08

A considerable amount of research has focused on monitoring structural damage using Structural Health Monitoring (SHM) technologies, which has had recent advances. However, it is important to note the challenges and unresolved problems that disqualify currently developed monitoring systems. One of the frontline SHM technologies, the Electromechanical Impedance (EMI) technique, has shown its potential to overcome remaining problems and challenges. Unfortunately, the recently developed neural network algorithms have not shown significant improvements in the accuracy of rate and the required processing time. In order to fill this gap in advanced neural networks used with EMI techniques, this paper proposes an enhanced and reliable strategy for improving the structural damage detection via: (1) Savitzky-Golay (SG) filter, using both first and second derivatives; (2) Probabilistic Neural Network (PNN); and, (3) Simplified Fuzzy ARTMAP Network (SFAN). Those three methods were employed to analyze the EMI data experimentally obtained from an aluminum plate containing three attached PZT (Lead Zirconate Titanate) patches. In this present study, the damage scenarios were simulated by attaching a small metallic nut at three different positions in the aluminum plate. We found that the proposed method achieves a hit rate of more than 83%, which is significantly higher than current state-of-the-art approaches. Furthermore, this approach results in an improvement of 93% when considering the best case scenario.

Use of Savitzky–Golay Filter for Performances Improvement of SHM Systems Based on Neural Networks and Distributed PZT Sensors

Science.gov (United States)

Araujo, Nelcileno V. S.; da Silva, Rodolfo N.; da Silva, Tony I.; Epaarachchi, Jayantha

2018-01-01

A considerable amount of research has focused on monitoring structural damage using Structural Health Monitoring (SHM) technologies, which has had recent advances. However, it is important to note the challenges and unresolved problems that disqualify currently developed monitoring systems. One of the frontline SHM technologies, the Electromechanical Impedance (EMI) technique, has shown its potential to overcome remaining problems and challenges. Unfortunately, the recently developed neural network algorithms have not shown significant improvements in the accuracy of rate and the required processing time. In order to fill this gap in advanced neural networks used with EMI techniques, this paper proposes an enhanced and reliable strategy for improving the structural damage detection via: (1) Savitzky–Golay (SG) filter, using both first and second derivatives; (2) Probabilistic Neural Network (PNN); and, (3) Simplified Fuzzy ARTMAP Network (SFAN). Those three methods were employed to analyze the EMI data experimentally obtained from an aluminum plate containing three attached PZT (Lead Zirconate Titanate) patches. In this present study, the damage scenarios were simulated by attaching a small metallic nut at three different positions in the aluminum plate. We found that the proposed method achieves a hit rate of more than 83%, which is significantly higher than current state-of-the-art approaches. Furthermore, this approach results in an improvement of 93% when considering the best case scenario. PMID:29316693

Use of Savitzky–Golay Filter for Performances Improvement of SHM Systems Based on Neural Networks and Distributed PZT Sensors

Directory of Open Access Journals (Sweden)

Mario A. de Oliveira

2018-01-01

Full Text Available A considerable amount of research has focused on monitoring structural damage using Structural Health Monitoring (SHM technologies, which has had recent advances. However, it is important to note the challenges and unresolved problems that disqualify currently developed monitoring systems. One of the frontline SHM technologies, the Electromechanical Impedance (EMI technique, has shown its potential to overcome remaining problems and challenges. Unfortunately, the recently developed neural network algorithms have not shown significant improvements in the accuracy of rate and the required processing time. In order to fill this gap in advanced neural networks used with EMI techniques, this paper proposes an enhanced and reliable strategy for improving the structural damage detection via: (1 Savitzky–Golay (SG filter, using both first and second derivatives; (2 Probabilistic Neural Network (PNN; and, (3 Simplified Fuzzy ARTMAP Network (SFAN. Those three methods were employed to analyze the EMI data experimentally obtained from an aluminum plate containing three attached PZT (Lead Zirconate Titanate patches. In this present study, the damage scenarios were simulated by attaching a small metallic nut at three different positions in the aluminum plate. We found that the proposed method achieves a hit rate of more than 83%, which is significantly higher than current state-of-the-art approaches. Furthermore, this approach results in an improvement of 93% when considering the best case scenario.

Lamb Wave Polarization Techniques for Structural Damage Localization and Quantification

Science.gov (United States)

2011-11-01

11  Figure 11. Images showing (a) fatigued aluminum dog bone specimen with 53-mm crack and (b) 3-D SLDV test...Abaqus* and a 3-D model of a plate girder. Experimental measurements using piezoelectric ( PZT ) sensors were located on the web in pulse-echo mode, and...analyzed mode conversion of T- joint with collocated PZT sensors before and after the stiffener using a 2-D simulation under plane strain assumptions

Optical and electro-optic anisotropy of epitaxial PZT thin films

Science.gov (United States)

Zhu, Minmin; Du, Zehui; Jing, Lin; Yoong Tok, Alfred Iing; Tong Teo, Edwin Hang

2015-07-01

Strong optical and electro-optic (EO) anisotropy has been investigated in ferroelectric Pb(Zr0.48Ti0.52)O3 thin films epitaxially grown on Nb-SrTiO3 (001), (011), and (111) substrates using magnetron sputtering. The refractive index, electro-optic, and ferroelectric properties of the samples demonstrate the significant dependence on the growth orientation. The linear electro-optic coefficients of the (001), (011), and (111)-oriented PZT thin films were 270.8, 198.8, and 125.7 pm/V, respectively. Such remarkable anisotropic EO behaviors have been explained according to the structure correlation between the orientation dependent distribution, spontaneous polarization, epitaxial strain, and domain pattern.

All-thin-film PZT/FeGa Multiferroic Cantilevers and Their Applications in Switching Devices and Parametric Amplification

Science.gov (United States)

Wang, Yi; Onuta, Tiberiu-Dan; Long, Chris; Lofland, Samuel; Takeuchi, Ichiro

2014-03-01

We are investigating the characteristics of microfabricated PZT/FeGa multiferroic cantilevers. The cantilevers can be driven by AC or DC magnetic and electric field, and the device response can be read off as a piezo-induced voltage. We can use the multiple input parameters to operate the devices in a variety of manners for different applications. They include electromagnetic energy harvesting, pulse triggered nonlinear memory devices, and parametrically amplified ME sensors. Due to the competition of anisotropy and Zeeman energies, the mechanical resonant frequency of the cantilevers was found to follow a hysteresis behavior with DC bias magnetic field applied in the cantilever easy axis. We can also control and tune the occurrence of nonlinear bifurcation in the frequency spectrum. The resulting hysteresis in the frequency spectrum can be used to make switching devices, where the input can be DC electric and magnetic fields, as well as pulses of AC fields. We have also demonstrated parametric pumping of the response from an AC magnetic field using frequency-doubled AC electric field. The enhanced equivalent ME coefficient is as high as 10 million V/(cm*Oe), when the pumping voltage is very close to a threshold voltage. The quality factor also increases from 2000 to 80000 with pumping.

Impact localization on composite structures using time difference and MUSIC approach

Science.gov (United States)

Zhong, Yongteng; Xiang, Jiawei

2017-05-01

1-D uniform linear array (ULA) has the shortcoming of the half-plane mirror effect, which does not allow discriminating between a target placed above the array and a target placed below the array. This paper presents time difference (TD) and multiple signal classification (MUSIC) based omni-directional impact localization on a large stiffened composite structure using improved linear array, which is able to perform omni-directional 360° localization. This array contains 2M+3 PZT sensors, where 2M+1 PZT sensors are arranged as a uniform linear array, and the other two PZT sensors are placed above and below the array. Firstly, the arrival times of impact signals observed by the other two sensors are determined using the wavelet transform. Compared with each other, the direction range of impact source can be decided in general, 0°to 180° or 180°to 360°. And then, two dimensional multiple signal classification (2D-MUSIC) based spatial spectrum formula using the uniform linear array is applied for impact localization by the general direction range. When the arrival times of impact signals observed by upper PZT is equal to that of lower PZT, the direction can be located in x axis (0°or 180°). And time difference based MUSIC method is present to locate impact position. To verify the proposed approach, the proposed approach is applied to a composite structure. The localization results are in good agreement with the actual impact occurring positions.

Tuning electro-optic susceptibity via strain engineering in artificial PZT multilayer films for high-performance broadband modulator

Science.gov (United States)

Zhu, Minmin; Du, Zehui; Li, Hongling; Chen, Bensong; Jing, Lin; Tay, Roland Ying Jie; Lin, Jinjun; Tsang, Siu Hon; Teo, Edwin Hang Tong

2017-12-01

A series of Pb(Zr1-xTix)O3 multilayer films alternatively stacked by Pb(Zr0.52Ti0.48)O3 and Pb(Zr0.35Ti0.65)O3 layers have been deposited on corning glass by magnetron sputtering. The films demonstrate pure perovskite structure and good crystallinity. A large tetragonality (c/a) of ∼1.061 and a shift of ∼0.08 eV for optical bandgap were investigated at layer engineered films. In addition, these samples exhibited a wild tunable electro-optic behavior from tens to ∼250.2 pm/V, as well as fast switching time of down to a few microseconds. The giant EO coefficient was attribute the strain-polarization coupling effect and also comparable to that of epitaxial (001) single crystal PZT thin films. The combination of high transparency, large EO effect, fast switching time, and huge phase transition temperature in PZT-based thin films show the potential on electro-optics from laser to information telecommunication.

Micro-fabrication technology for piezoelectric film formation and its application to MEMS

OpenAIRE

一木, 正聡; 曹, 俊杰; 張, 麓〓; 王, 占杰; 前田, 龍太郎; Masaaki, ICHIKI; Jiunn Jye, TSAUR; Lulu, ZHANG; Zhang Jie, WANG; Ryutaro, MAEDA; 産業技術総合研究所; 産業技術総合研究所; 産業技術総合研究所; 東北大学; 産業技術総合研究所

2005-01-01

Technological problems for realization of Micro Electro-mechanical System (MEMS) are discussed and an introduction of smart materials (PZT) is encouraged. The film formation and micromaching technology are discussed in integration of PZT thin films into MEMS. Further developments are proposed on PZT micro sensors and actuators with special emphasis laid on exploration of new application fields of MEMS, such as scanning mirror. Internal stress is estimated and analyzed for the improvement of d...

Electric field-controlled magnetization in exchange biased IrMn/Co/PZT multilayers

International Nuclear Information System (INIS)

Huong Giang, D T; Duc, N H; Agnus, G; Maroutian, T; Lecoeur, P

2013-01-01

Electric-field modulating exchange bias and near 180° deterministic magnetization switching at room temperature are demonstrated in simple antiferromagnetic/ferromagnetic/ferroelectric (AFM/FM/FE) exchange-coupled multiferroic multilayers of IrMn/Co/PZT. A rather large exchange bias field shift up to ΔH ex /H ex = 500% was obtained. This change governs mainly the electric-field strength rather than the applied current. It is explained as being realized through the competition between the electric-field induced uniaxial and unidirectional anisotropies. These results show good prospects for low-power spintronic devices. (paper)

Shape and size effects on layered Ni/PZT/Ni composites magnetoelectric performance

Energy Technology Data Exchange (ETDEWEB)

Pan, D A; Zhang, S G; Qiao, L J [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Volinsky, Alex A [Department of Mechanical Engineering, University of South Florida, Tampa FL 33620 (United States)], E-mail: lqiao@ustb.edu.cn

2008-09-07

This paper presents the magnetoelectric (ME) effect in trilayered Ni/PZT/Ni composites which is related to their size and shape. The ME composites with the same interfacial areas but different geometrical shapes have different ME voltage coefficients. Longitudinal resonant modes in the rectangular and triangular trilayered ME composites were studied. One should choose optimized size, shape and working frequency of the ME composites in order to gain the maximum ME effect. This study plays a guiding role for trilayered ME composites design for real applications. (fast track communication)

Microestructura y propiedades de materiales cerámicos PZT con control de crecimiento de grano

Directory of Open Access Journals (Sweden)

Celi, L. A.

1999-10-01

Full Text Available Lead zirconate titanate ceramic powders have been surface modified by using phosphor esther 0.3% in volume. The phosphorous modification gave higher densities at lower temperatures associated with a reduction of the weight losses during the densification process. From the relationships between ceramic processing and microstructure, it was established that the phosphorous surface modification allows the effective grain growth control as well a higher homogeneity in the grain size distribution.

Se ha realizado un proceso de modificación superficial con ester fosfato al 0.3% en volumen, sobre polvo cerámico de titanato circonato de plomo, PZT. Se observa que el material modificado con fósforo presenta una mayor densificación aparente a una temperatura menor unida a una reducción de las pérdidas de peso durante el proceso de densificación. Se han establecido las relaciones entre el procesamiento y las microestructuras del material PZT sin modificar y el modificado. Se evidencia un control del crecimiento de grano y una mayor homogeneidad en la distribución de tamaños de grano en el material modificado.

A comparative approach to predicting effective dielectric, piezoelectric and elastic properties of PZT/PVDF composites

International Nuclear Information System (INIS)

Ahmad, Zeeshan; Prasad, Ashutosh; Prasad, K.

2009-01-01

The present study addresses the problem of quantitative prediction of effective relative permittivity, dielectric loss factor, piezoelectric charge coefficient, and Young's modulus of PZT/PVDF diphasic ceramic-polymer composite as a function of volume fraction of PZT in the different compositions. Theoretical results for effective relative permittivity derived from several dielectric mixture equations like those of Knott, Rother-Lichtenecker, Bruggeman, Maxwell-Wagner-Webmann-Skipetrov or Dias-Dasgupta, Furukawa, Lewin, Wiener, Jayasundere-Smith, Modified Cule-Torquato, Taylor, Poon-Shin and Rao et al. were fitted to the experimental data taken from previous works of Yamada et al. Similarly, the results for effective piezoelectric coefficient and Young's modulus, derived from different appropriate equations were fitted to the corresponding experimental data taken from the literature. The study revealed that only a few equations like modified Rother-Lichtenecker equation, Dias-Dasgupta equation and Rao equation for dielectric and piezoelectric properties while the four new equations developed in the present study of elastic property (Young's modulus) well fitted the corresponding experimental results. Further, the acceptable data put to various regression analyses showed that in most of the cases the third order polynomial regression analysis provided more acceptable fits.

Polarization-dependent interfacial coupling modulation of ferroelectric photovoltaic effect in PZT-ZnO heterostructures.

Science.gov (United States)

Pan, Dan-Feng; Bi, Gui-Feng; Chen, Guang-Yi; Zhang, Hao; Liu, Jun-Ming; Wang, Guang-Hou; Wan, Jian-Guo

2016-03-08

Recently, ferroelectric perovskite oxides have drawn much attention due to potential applications in the field of solar energy conversion. However, the power conversion efficiency of ferroelectric photovoltaic effect currently reported is far below the expectable value. One of the crucial problems lies in the two back-to-back Schottky barriers, which are formed at the ferroelectric-electrode interfaces and blocking most of photo-generated carriers to reach the outside circuit. Herein, we develop a new approach to enhance the ferroelectric photovoltaic effect by introducing the polarization-dependent interfacial coupling effect. Through inserting a semiconductor ZnO layer with spontaneous polarization into the ferroelectric ITO/PZT/Au film, a p-n junction with strong polarization-dependent interfacial coupling effect is formed. The power conversion efficiency of the heterostructure is improved by nearly two orders of magnitude and the polarization modulation ratio is increased about four times. It is demonstrated that the polarization-dependent interfacial coupling effect can give rise to a great change in band structure of the heterostructure, not only producing an aligned internal electric field but also tuning both depletion layer width and potential barrier height at PZT-ZnO interface. This work provides an efficient way in developing highly efficient ferroelectric-based solar cells and novel optoelectronic memory devices.

A piezoelectric micro generator worked at low frequency and high acceleration based on PZT and phosphor bronze bonding.

Science.gov (United States)

Tang, Gang; Yang, Bin; Hou, Cheng; Li, Guimiao; Liu, Jingquan; Chen, Xiang; Yang, Chunsheng

2016-12-08

Recently, piezoelectric energy harvesters (PEHs) have been paid a lot of attention by many researchers to convert mechanical energy into electrical and low level vibration. Currently, most of PEHs worked under high frequency and low level vibration. In this paper, we propose a micro cantilever generator based on the bonding of bulk PZT wafer and phosphor bronze, which is fabricated by MEMS technology, such as mechanical chemical thinning and etching. The experimental results show that the open-circuit output voltage, output power and power density of this fabricated prototype are 35 V, 321 μW and 8664 μW cm -3 at the resonant frequency of 100.8 Hz, respectively, when it matches an optimal loading resistance of 140 kΩ under the excitation of 3.0 g acceleration. The fabricated micro generator can obtain the open-circuit stable output voltage of 61.2 V when the vibration acceleration arrives at 7.0 g. Meanwhile, when this device is pasted on the vibrating vacuum pump, the output voltage is about 11 V. It demonstrates that this novel proposed device can scavenge high vibration level energy at low frequency for powering the inertial sensors in internet of things application.

Development and characterization of silicone embedded distributed piezoelectric sensors for contact detection

International Nuclear Information System (INIS)

Acer, Merve; Salerno, Marco; Paik, Jamie; Agbeviade, Kossi

2015-01-01

Tactile sensing transfers complex interactive information in a most intuitive sense. Such a populated set of data from the environment and human interactions necessitates various degrees of information from both modular and distributed areas. A sensor design that could provide such types of feedback becomes challenging when the target component has a nonuniform, agile, high resolution, and soft surface. This paper presents an innovative methodology for the manufacture of novel soft sensors that have a high resolution sensing array due to the sensitivity of ceramic piezoelectric (PZT) elements, while uncommonly matched with the high stretchability of the soft substrate and electrode design. Further, they have a low profile and their transfer function is easy to tune by changing the material and thickness of the soft substrate in which the PZTs are embedded. In this manuscript, we present experimental results of the soft sensor prototypes: PZTs arranged in a four by two array form, measuring 1.5–2.3 mm in thickness, with the sensitivity in the range of 0.07–0.12 of the normalized signal change per unit force. We have conducted extensive tests under dynamic loading conditions that include impact, step and cyclic. The presented prototype's mechanical and functional capacities are promising for applications in biomedical systems where soft, wearable and high precision sensors are needed. (paper)

Development and characterization of silicone embedded distributed piezoelectric sensors for contact detection

Science.gov (United States)

Acer, Merve; Salerno, Marco; Agbeviade, Kossi; Paik, Jamie

2015-07-01

Tactile sensing transfers complex interactive information in a most intuitive sense. Such a populated set of data from the environment and human interactions necessitates various degrees of information from both modular and distributed areas. A sensor design that could provide such types of feedback becomes challenging when the target component has a nonuniform, agile, high resolution, and soft surface. This paper presents an innovative methodology for the manufacture of novel soft sensors that have a high resolution sensing array due to the sensitivity of ceramic piezoelectric (PZT) elements, while uncommonly matched with the high stretchability of the soft substrate and electrode design. Further, they have a low profile and their transfer function is easy to tune by changing the material and thickness of the soft substrate in which the PZTs are embedded. In this manuscript, we present experimental results of the soft sensor prototypes: PZTs arranged in a four by two array form, measuring 1.5-2.3 mm in thickness, with the sensitivity in the range of 0.07-0.12 of the normalized signal change per unit force. We have conducted extensive tests under dynamic loading conditions that include impact, step and cyclic. The presented prototype's mechanical and functional capacities are promising for applications in biomedical systems where soft, wearable and high precision sensors are needed.

Adaptive Robust Sliding Mode Vibration Control of a Flexible Beam Using Piezoceramic Sensor and Actuator: An Experimental Study

Directory of Open Access Journals (Sweden)

Ruo Lin Wang

2014-01-01

Full Text Available This paper presents an experimental study of an adaptive robust sliding mode control scheme based on the Lyapunov’s direct method for active vibration control of a flexible beam using PZT (lead zirconate titanate sensor and actuator. PZT, a type of piezoceramic material, has the advantages of high reliability, high bandwidth, and solid state actuation and is adopted here in forms of surface-bond patches for vibration control. Two adaptive robust sliding mode controllers for vibration suppression are designed: one uses a discontinuous bang-bang robust compensator and the other uses a smooth compensator with a hyperbolic tangent function. Both controllers guarantee asymptotic stability, as proved by the Lyapunov’s direct method. Experimental results verified the effectiveness and the robustness of both adaptive sliding mode controllers. However, from the experimental results, the bang-bang robust compensator causes small-magnitude chattering because of the discontinuous switching actions. With the smooth compensator, vibration is quickly suppressed and no chattering is induced. Furthermore, the robustness of the controllers is successfully demonstrated with ensured effectiveness in vibration control when masses are added to the flexible beam.

Lamb Wave Propagation in a Restricted Geometry Composite PI-Joint Specimen (Preprint)

Science.gov (United States)

2011-11-01

adhesive, and were located along the length and height of the specimen as depicted in Figure 3. The sensors were 6.35 mm round disks of PZT , with a...in both cases for R1, R2, and R3. 3D Finite Element Model Geometry 200mm length 50mm width 140mm height x z y PZT Actuation Sensor...health monitoring using scanning laser vibrometry: III. Lamb waves for fatigue crack detection”, Smart Mater. Struct., Vol. 14, No. 6, 2005. 16

Compositional dependence of the Young's modulus and piezoelectric coefficient of (110)-oriented pulsed laser deposited PZT thin films

NARCIS (Netherlands)

Nazeer, H.; Nguyen, Duc Minh; Rijnders, Augustinus J.H.M.; Sardan Sukas, Ö.; Abelmann, Leon; Elwenspoek, Michael Curt

2014-01-01

In this contribution, we report on the compositional dependence of the mechanical and piezoelectric properties of Pb(ZrₓTi₿₋ₓ)O₃ (PZT) thin films fabricated by pulsed laser deposition (PLD). These films grow epitaxially on silicon with a (110) preferred orientation and have excellent piezoelectric

Design and fabrication of a piezoelectric mode 2 sensor based on optical modulated liquid crystal and spiropyran

International Nuclear Information System (INIS)

Chen, Kuan-Ting; Lee, Chih-Kung; Chang, Chin-Kai; Kuo, Hui-Lung

2011-01-01

In this paper, we propose an innovative photoelectric material made of a mixture of liquid crystal and spiropyran which can be used to tailor the performance of piezoelectric sensors. The impedance variation of this photoelectric material can be controlled using different ultraviolet (UV) irradiation times. We found that the impedance of the liquid crystal–spiropyran mixture remains stable after the UV irradiation. Results showed that UV irradiation at 180 s resulted in the lowest mixture impedance. It appears that the electrical properties of the mixture have great potential to modulate a piezoelectric system since UV irradiation can be used to tailor the impedance of a photosensitive electrode made of a liquid crystal–spiropyran sensor for PZT (i.e. lead zirconate titanate) modal actuator/sensor applications. The main innovation of this paper is the demonstration of a new approach towards producing a positive and negative bias voltage in different regions of a sensor by using UV illumination for different time periods. A one-dimensional mode 2 sensor for a cantilever beam was designed and tested to verify the validity of this innovative approach. Since UV illumination can be changed in situ or in real time, this research also represents the creation of an optically defined/tailored modal sensor. In the future, a two-dimensional optical modal control could also be obtained using the method demonstrated

Sinterização ultrarrápida por micro-ondas de compósitos particulados PZT/FCO preparados por mistura em ultrassom

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C. P. Fernandez

Full Text Available Resumo Pós de Pb(Zr0,53Ti0,47O3 (PZT e Fe2CoO4 (FCO, foram sintetizados separadamente pelo método Pechini e misturados em ultrassom, nas proporções molares 80/20 e 50/50 (PZT/FCO. Os compósitos preparados foram prensados e submetidos à sinterização em forno convencional e sinterização ultrarrápida assistida por micro-ondas. A caracterização estrutural e microestrutural das amostras foram realizadas por difração de raios X e microscopia eletrônica de varredura, respectivamente. Medidas de constante dielétrica em função da temperatura, resistividade elétrica e coeficiente de acoplamento magnetoelétrico foram também realizadas. Os resultados evidenciaram que o método de mistura do PZT com a FCO por ultrassom foi rápido e eficiente, gerando, após sinterização, compósitos particulados com conectividade global (0-3 e distribuição uniforme de grãos da fase ferromagnética (FCO na matriz ferroelétrica (PZT. Da análise estrutural, verificou-se que a sinterização por micro-ondas propiciou um arranjo diferenciado no esquema de conectividade local na amostra (1-3 e (2-3, relacionada com a intensificação dos processos de difusão que ocorrem nesse tipo de sinterização principalmente em sistemas nanométricos. Pelos altos valores de resistividade obtidos, comprovou-se que a integridade das fases foi conservada nos dois métodos de sinterização, sendo mais eficiente na sinterização por micro-ondas, característica que garantiu o comportamento magnetoelétrico em todos os compósitos estudados neste trabalho. Os valores do campo Hmax foram dependentes da concentração da fase ferrita e da sinterização; para a composição 80/20 de 1,4 e 1,9 kOe, e para 50/50 de 3,5 e 3,0 kOe nas amostras sinterizadas por micro-ondas e convencionalmente, compatíveis com a literatura e que confirmaram a integridade das fases constituintes PZT e FCO.

Influences of donor dopants on the properties of PZT-PMS-PZN piezoelectric ceramics sintered at low temperatures

International Nuclear Information System (INIS)

Yoon, Seokjin; Choi, Jiwon; Choi, Jooyoung; Wan, Dandan; Li, Qian; Yang, Ying

2010-01-01

0.90Pb(Zr 0.48 Ti 0.52 )O 3 -0.05Pb(Mn 1/3 Sb 2/3 )O 3 -0.05Pb(Zn 1/3 Nb 2/3 )O 3 quaternary piezoelectric ceramics with CuO added were synthesized by using a conventional method at low sintering temperatures. CuO additive, 1.0 wt%, significantly improves the sinterability of 0.90PZT-0.05PMS-0.05PZN ceramics, lowering the sintering temperature to 900 .deg. C and showing moderate electrical properties: d 33 = 306 pC/N, Q m = 997, k p = 53.6%, tanδ = 0.50%, and ε T 33 = 1351. To obtain more optimal piezoelectric properties, we selected Bi 2 O 3 and Nb 2 O 5 as donor dopants to introduce a softening effect. The crystal structure, micro-morphology and electrical properties were studied in terms of the Bi 2 O 3 and the Nb 2 O 5 contents. Our study demonstrates that Bi 2 O 3 is very effective in improving the piezoelectric properties, causing a significant enhancement in d 33 and k p values. Particularly, 0.75-wt%-Bi 2 O 3 -added 0.90PZT-0.05PMS-0.05PZN + 1.0 wt% CuO ceramics show excellent electrical properties: d 33 = 363 pC/N, Q m = 851, k p = 59.3%, tanδ = 0.38%, and ε T 33 = 1596. On the other hand, the effect of Nb 2 O 5 on the piezoelectric properties is very complicated, 0.50 wt% Nb 2 O 5 doped 0.90PZT-0.05PMS-0.05PZN + 1.0 wt% CuO ceramics have a remarkable improvement in k p value and maintain good electrical properties: d 33 = 300 pC/N, Q m = 971, k p = 58.4%, tanδ = 0.36%, and ε T 33 = 1332.

Template-based electrophoretic deposition of perovskite PZT nanotubes

Energy Technology Data Exchange (ETDEWEB)

Nourmohammadi, A. [Solid Surfaces Analysis and Electron Microscopy Group, Institute of Physics, Chemnitz University of Technology, D-09126 Chemnitz (Germany); Semiconductors Department, Materials and Energy Research Center (MERC), 31779-83634 Karaj (Iran, Islamic Republic of); Bahrevar, M.A. [Semiconductors Department, Materials and Energy Research Center (MERC), 31779-83634 Karaj (Iran, Islamic Republic of)], E-mail: ma.bahrevar@yahoo.com; Hietschold, M. [Solid Surfaces Analysis and Electron Microscopy Group, Institute of Physics, Chemnitz University of Technology, D-09126 Chemnitz (Germany)

2009-04-03

Template-based electrophoretic deposition of perovskite lead zirconate titanate (PZT) nanotubes was achieved using anodic alumina (AA) membranes and sols, containing lead, zirconium and titanium precursors. The effect of various anodizing voltages on the size of the channels in the anodic alumina template was investigated. The prepared sol was driven into the channels under the influence of various electric fields and subsequently sintered at about 700 deg. C. The effects of the initial heating rates and the burn-out temperature on the phase evolution of the samples were studied and a modified firing process was employed. The effects of the electrophoretic voltage and the deposition time on the average wall thickness of the tubes were investigated. Scanning and transmission electron microscopy (SEM and TEM) revealed the efficiency of electrophoresis in the growth of lead zirconate titanate nanotubes in a close-packed array. The X-ray diffraction analyses indicated the presence of perovskite as the principal phase after a modified firing schedule.

Theoretical and Experimental Study on Secondary Piezoelectric Effect Based on PZT-5

International Nuclear Information System (INIS)

Zhang, Z H; Sun, B Y; Shi, L P

2006-01-01

The purpose of this paper is to confirm the existence of secondary and multiple piezoelectric effect theoretically and experimentally. Based on Heckmann model showing the relationship among mechanical, electric and heat energy and the physical model on mechanical, electric, heat, and magnetic energy, theoretical analysis of multiple piezoelectric effect is made through four kinds of piezoelectric equations. Experimental research of secondary direct piezoelectric effect is conducted through adopting PZT-5 piles. The result of the experiment indicates that charge generated by secondary direct piezoelectric effect as well as displacement caused by first converse piezoelectric effect keeps fine linearity with the applied voltage

Optimized electrode coverage of membrane actuators based on epitaxial PZT thin films

International Nuclear Information System (INIS)

Nguyen, M D; Dekkers, M; Blank, D H A; Rijnders, G; Nazeer, H

2013-01-01

This research presents an optimization of piezoelectric membrane actuators by maximizing the actuator displacement. Membrane actuators based on epitaxial Pb(Zr,Ti)O 3 thin films grown on all-oxide electrodes and buffer layers using silicon technology were fabricated. Electrode coverage was found to be an important factor in the actuation displacement of the piezoelectric membranes. The optimum electrode coverage for maximum displacement was theoretically determined to be 39%, which is in good agreement with the experimental results. Dependences of membrane displacement and optimum electrode coverage on membrane diameter and PZT-film/Si-device-layer thickness ratio have also been investigated. (paper)

Cross-sectional analysis of ferroelectric domains in PZT capacitors via piezoresponse force microscopy

Energy Technology Data Exchange (ETDEWEB)

Liu, J S [School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang City (China); Zeng, H Z [State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Kholkin, A L [Department of Ceramic and Glass Engineering and CICECO, University of Aveiro, Aveiro 3810-193 (Portugal)

2007-11-21

Ferroelectric domains have been investigated on the cross-section of Pb(Zr{sub 0.55}Ti{sub 0.45})O{sub 3} (PZT) thin film capacitors by scanning probe microscopy. The static domain images on the cross-section were obtained by the lateral piezoresponse force microscopy (LPFM) method, in which the ac voltage used to induce the converse piezoelectric effect was applied between the conductive tip and the bottom electrode. The polarization component normal to the substrate could be characterized via both d{sub 33} and d{sub 15} piezoelectric coefficients, which resulted in a high resolution of LPFM images. After a variable dc bias was applied between the top and the bottom electrodes, the variations of domain image on the cross-section were recorded by the LPFM immediately. Upon the application of low bias, new domain sites appeared near the PZT/Pt interface opposite to the initial polarization. Forward stretch of new domains was facilitated under the dc field approaching the coercive field E{sub c}. Under a very high field (about three times of the E{sub c}), the sidewise expansion of columnar domains was observed. However, the domains were only partially switched even though a very high field was applied. The observed domain growth process indicated a lower energy barrier for nucleation compared with that of domain wall motion. Possible reasons for the incomplete switching are the substantial influences of the interface and depolarization in thin film capacitors.

A low-frequency MEMS piezoelectric energy harvester with a rectangular hole based on bulk PZT film

Science.gov (United States)

Tian, Yingwei; Li, Guimiao; Yi, Zhiran; Liu, Jingquan; Yang, Bin

2018-06-01

This paper presents a high performance piezoelectric energy harvester (PEH) with a rectangular hole to work at low-frequency. This PEH used thinned bulk PZT film on flexible phosphor bronze, and its structure included piezoelectric layer, supporting layer and proof mass to reduce the resonant frequency of the device. Here, thinned bulk PZT thick film was used as piezoelectric layer due to its high piezoelectric coefficient. A Phosphor bronze was deployed as supporting layer because it had better flexibility compared to silicon and could work under high acceleration ambient with good durability. The maximum open-circuit voltage of the PEH was 15.7 V at low resonant frequency of 34.3 Hz when the input vibration acceleration was 1.5 g (g = 9.81 m/s2). Moreover, the maximum output power, the output power density and the actually current at the same acceleration were 216.66 μW, 1713.58 μW/cm3 and 170 μA, respectively, when the optimal matched resistance of 60 kΩ was connected. The fabricated PEH scavenged the vibration energy of the vacuum compression pump and generated the maximum output voltage of 1.19 V.

Influence of silicon orientation and cantilever undercut on the determination of Young's modulus of pulsed laser deposited PZT

NARCIS (Netherlands)

Nazeer, H.; Woldering, L.A.; Abelmann, Leon; Nguyen, Duc Minh; Rijnders, Augustinus J.H.M.; Elwenspoek, Michael Curt

In this work we show for the first time that the effective in-plane Young’s modulus of PbZr0.52Ti0.48O3 (PZT) thin films, deposited by pulsed laser deposition (PLD) on dedicated single crystal silicon cantilevers, is independent of the in-plane orientation of cantilevers.

High-performance piezoelectric thick film based energy harvesting micro-generators for MEMS

DEFF Research Database (Denmark)

Zawada, Tomasz; Hansen, Karsten; Lou-Moeller, Rasmus

2010-01-01

and are transformed by the energy harvesting micro-generator into usable electrical signal. The micro-generator comprises a silicon cantilever with integrated InSensor® TF2100 PZT thick film deposited using screen-printing. The output power versus frequency and electrical load has been investigated. Furthermore......, devices based on modified, pressure treated thick film materials have been tested and compared with the commercial InSensor® TF2100 PZT thick films. It has been found that the structures based on the pressure treated materials exhibit superior properties in terms of energy output....

Piezoelectric Resonance Defined High Performance Sensors and Modulators

Science.gov (United States)

2016-05-30

19.00 20.00 30.00 Received Paper 3.00 Juan P. Tamez, Amar Bhalla, Ruyan Guo. Design and Simulation of 100 kHz and 200 kHz Tri-Phasic PZT Piezoelectric...electrooptic coefficient r_51 of tetragonal potassium lithium tantalate niobate K_095Li_005Ta_040Nb_060O_3 single crystal, Optical Materials Express, (11...Experimental Studies on Tri- Phasic PZT Piezoelectric Transducer, Ferroelectrics, (12 2014): 0. doi: 10.1080/00150193.2014.974472 Jun Li, Yang Li

Effects of electric field on the fracture toughness (KIc) of ceramic PZT

International Nuclear Information System (INIS)

Goljahi, Sam; Lynch, Christopher S

2013-01-01

This work was motivated by the observation that a small percentage of the ceramic lead zirconate titanate (PZT) parts in a device application, one that requires an electrode pattern on the PZT surface, developed fatigue cracks at the edges of the electrodes; yet all of the parts were subjected to similar loading. To obtain additional information on the fracture behavior of this material, similar specimens were run at higher voltage in the laboratory under a microscope to observe the initiation and growth of the fatigue cracks. A sequence of experiments was next performed to determine whether there were fracture toughness variations that depended on material processing. Plates were cut from a single bar in different locations and the Vickers indentation technique was used to measure the relative fracture toughness as a function of position along the bar. Small variations in toughness were found, that may account for some of the devices developing fatigue cracks and not others. Fracture toughness was measured next as a function of electric field. The surface crack in flexure technique was modified to apply an electric field perpendicular to a crack. The results indicate that the fracture toughness drops under a positive electric field and increases under a negative electric field that is less than the coercive field, but as the negative coercive field is approached the fracture toughness drops. Examination of the fracture surfaces using an optical microscope and a surface profilometer reveal the initial indentation crack shape and (although less accurately) the crack shape and size at the transition from stable to unstable growth. These results are discussed in terms of a ferroelastic toughening mechanism that is dependent on electric field. (paper)

Effects of electric field on the fracture toughness (KIc) of ceramic PZT

Science.gov (United States)

Goljahi, Sam; Lynch, Christopher S.

2013-09-01

This work was motivated by the observation that a small percentage of the ceramic lead zirconate titanate (PZT) parts in a device application, one that requires an electrode pattern on the PZT surface, developed fatigue cracks at the edges of the electrodes; yet all of the parts were subjected to similar loading. To obtain additional information on the fracture behavior of this material, similar specimens were run at higher voltage in the laboratory under a microscope to observe the initiation and growth of the fatigue cracks. A sequence of experiments was next performed to determine whether there were fracture toughness variations that depended on material processing. Plates were cut from a single bar in different locations and the Vickers indentation technique was used to measure the relative fracture toughness as a function of position along the bar. Small variations in toughness were found, that may account for some of the devices developing fatigue cracks and not others. Fracture toughness was measured next as a function of electric field. The surface crack in flexure technique was modified to apply an electric field perpendicular to a crack. The results indicate that the fracture toughness drops under a positive electric field and increases under a negative electric field that is less than the coercive field, but as the negative coercive field is approached the fracture toughness drops. Examination of the fracture surfaces using an optical microscope and a surface profilometer reveal the initial indentation crack shape and (although less accurately) the crack shape and size at the transition from stable to unstable growth. These results are discussed in terms of a ferroelastic toughening mechanism that is dependent on electric field.

Design, Fabrication, and Modeling of a Novel Dual-Axis Control Input PZT Gyroscope

Directory of Open Access Journals (Sweden)

Cheng-Yang Chang

2017-10-01

Full Text Available Conventional gyroscopes are equipped with a single-axis control input, limiting their performance. Although researchers have proposed control algorithms with dual-axis control inputs to improve gyroscope performance, most have verified the control algorithms through numerical simulations because they lacked practical devices with dual-axis control inputs. The aim of this study was to design a piezoelectric gyroscope equipped with a dual-axis control input so that researchers may experimentally verify those control algorithms in future. Designing a piezoelectric gyroscope with a dual-axis control input is more difficult than designing a conventional gyroscope because the control input must be effective over a broad frequency range to compensate for imperfections, and the multiple mode shapes in flexural deformations complicate the relation between flexural deformation and the proof mass position. This study solved these problems by using a lead zirconate titanate (PZT material, introducing additional electrodes for shielding, developing an optimal electrode pattern, and performing calibrations of undesired couplings. The results indicated that the fabricated device could be operated at 5.5±1 kHz to perform dual-axis actuations and position measurements. The calibration of the fabricated device was completed by system identifications of a new dynamic model including gyroscopic motions, electromechanical coupling, mechanical coupling, electrostatic coupling, and capacitive output impedance. Finally, without the assistance of control algorithms, the “open loop sensitivity” of the fabricated gyroscope was 1.82 μV/deg/s with a nonlinearity of 9.5% full-scale output. This sensitivity is comparable with those of other PZT gyroscopes with single-axis control inputs.

Design, Fabrication, and Modeling of a Novel Dual-Axis Control Input PZT Gyroscope.

Science.gov (United States)

Chang, Cheng-Yang; Chen, Tsung-Lin

2017-10-31

Conventional gyroscopes are equipped with a single-axis control input, limiting their performance. Although researchers have proposed control algorithms with dual-axis control inputs to improve gyroscope performance, most have verified the control algorithms through numerical simulations because they lacked practical devices with dual-axis control inputs. The aim of this study was to design a piezoelectric gyroscope equipped with a dual-axis control input so that researchers may experimentally verify those control algorithms in future. Designing a piezoelectric gyroscope with a dual-axis control input is more difficult than designing a conventional gyroscope because the control input must be effective over a broad frequency range to compensate for imperfections, and the multiple mode shapes in flexural deformations complicate the relation between flexural deformation and the proof mass position. This study solved these problems by using a lead zirconate titanate (PZT) material, introducing additional electrodes for shielding, developing an optimal electrode pattern, and performing calibrations of undesired couplings. The results indicated that the fabricated device could be operated at 5.5±1 kHz to perform dual-axis actuations and position measurements. The calibration of the fabricated device was completed by system identifications of a new dynamic model including gyroscopic motions, electromechanical coupling, mechanical coupling, electrostatic coupling, and capacitive output impedance. Finally, without the assistance of control algorithms, the "open loop sensitivity" of the fabricated gyroscope was 1.82 μV/deg/s with a nonlinearity of 9.5% full-scale output. This sensitivity is comparable with those of other PZT gyroscopes with single-axis control inputs.

Flexible Piezoelectric Generators by Using the Bending Motion Method of Direct-Grown-PZT Nanoparticles on Carbon Nanotubes.

Science.gov (United States)

Han, Jin Kyu; Jeon, Do Hyun; Cho, Sam Yeon; Kang, Sin Wook; Lim, Jongsun; Bu, Sang Don

2017-10-07

Recently, composite-type nanogenerators (NGs) formed from piezoelectric nanostructures and multi-walled carbon nanotubes (CNTs), have become one of the excellent candidates for future energy harvesting because of their ability to apply the excellent electrical and mechanical properties of CNTs. However, the synthesis of NG devices with a high proportion of piezoelectric materials and a low polymer content, such as of polydimethylsiloxane (PDMS), continues to be problematic. In this work, high-piezoelectric-material-content flexible films produced from Pb(Zr,Ti)O₃ (PZT)-atomically-interconnected CNTs and polytetrafluoroethylene (PTFE) are presented. Various physical and chemical characterization techniques are employed to examine the morphology and structure of the materials. The direct growth of the piezoelectric material on the CNTs, by stirring the PZT and CNT mixed solution, results in various positive effects, such as a high-quality dispersion in the polymer matrix and addition of flexoelectricity to piezoelectricity, resulting in the enhancement of the output voltage by an external mechanical force. The NGs repeatedly generate an output voltage of 0.15 V. These results present a significant step toward the application of NGs using piezoelectric nanocomposite materials.

Flexible Piezoelectric Generators by Using the Bending Motion Method of Direct-Grown-PZT Nanoparticles on Carbon Nanotubes

Directory of Open Access Journals (Sweden)

Jin Kyu Han

2017-10-01

Full Text Available Recently, composite-type nanogenerators (NGs formed from piezoelectric nanostructures and multi-walled carbon nanotubes (CNTs, have become one of the excellent candidates for future energy harvesting because of their ability to apply the excellent electrical and mechanical properties of CNTs. However, the synthesis of NG devices with a high proportion of piezoelectric materials and a low polymer content, such as of polydimethylsiloxane (PDMS, continues to be problematic. In this work, high-piezoelectric-material-content flexible films produced from Pb(Zr,TiO3 (PZT-atomically-interconnected CNTs and polytetrafluoroethylene (PTFE are presented. Various physical and chemical characterization techniques are employed to examine the morphology and structure of the materials. The direct growth of the piezoelectric material on the CNTs, by stirring the PZT and CNT mixed solution, results in various positive effects, such as a high-quality dispersion in the polymer matrix and addition of flexoelectricity to piezoelectricity, resulting in the enhancement of the output voltage by an external mechanical force. The NGs repeatedly generate an output voltage of 0.15 V. These results present a significant step toward the application of NGs using piezoelectric nanocomposite materials.

Influencia de las diferentes etapas de procesamiento sobre la microestructura de dispositivos multicapa basados en PZT

Directory of Open Access Journals (Sweden)

Solera, E.

2002-02-01

Full Text Available A comparative study of the influence of both rheological and processing parameters on the microstructure and reliability of multilayer ceramic chips based on PZT has been conducted. The multilayer chips were obtained by tape casting. Viscosity measurements of different slurries with various solids content have been correlated with both the thickness and the green density of the casted layers. The critical points of the thermal treatments, organics burn-out and sintering, have been identified. The green microstructure of the layers and the final microstructure of the sintered chips have been studied by SEM.

Se ha realizado un estudio comparativo de la influencia de los parámetros reológicos y de procesamiento sobre la microestructura y consistencia de chips multicapa de PZT obtenidos mediante un proceso de colado en cinta. Para ello se han realizado medidas de viscosidad de distintas barbotinas con diferente contenido en sólidos y su relación con el espesor y densidad en verde de las cintas obtenidas, se han identificado los puntos críticos del ciclo de quemado-sinterización y, mediante MEB se ha estudiado la microestructura en verde de las láminas coladas y la microestructura final de los chips multicapa fabricados.

Fabrication of microstructures in aviation components with a femtosecond laser based on PZT scanning

International Nuclear Information System (INIS)

Yang, Xiaojun; Zhao, Wei; Li, Ming; Yang, Yong; Cheng, Guanghua; Zhao, Hualong; Li, Peng; Zhang, Huixing

2013-01-01

Thermal defects and low precision are the main disadvantages of fabricating micro-holes, irregular holes, and micro-slots in thermostable aviation materials. We demonstrate a manufacturing method employing a femtosecond laser and piezoelectric ceramic (PZT). The production process parameters were optimized according to the metallographic and dimensional accuracy of the microstructure, which was measured by phase-contrast microscopy and scanning electron microscopy. The limitations in a conventional aeroengine, such as in the recast layer, recrystallization, and micro-cracks, which degrade the performance and service life, were resolved with a simple, controllable, and commercial method. (paper)

The effect of calcining temperature on the properties of 0-3 piezoelectric composites of PZT and a liquid crystalline thermosetting polymer

NARCIS (Netherlands)

Ende, D.A. van den; Groen, W.A.; Zwaag, S. van der

2011-01-01

We report on the optimisation of a recently developed high performance 0-3 piezoelectric composite comprising of the piezoelectric Lead Zirconate Titanate (PZT) powder and a liquid crystalline thermosetting matrix polymer (LCT). The matrix polymer is a liquid crystalline polymer comprising of an

Powering autonomous sensors with miniaturized piezoelectric based energy harvesting devices operating at very low frequency

Science.gov (United States)

Ferin, G.; Bantignies, C.; Le Khanh, H.; Flesch, E.; Nguyen-Dinh, A.

2015-12-01

Harvesting energy from ambient mechanical vibrations is a smart and efficient way to power autonomous sensors and support innovative developments in IoT (Internet of Things), WSN (Wireless Sensor Network) and even implantable medical devices. Beyond the environmental operating conditions, efficiency of such devices is mainly related to energy source properties like the amplitude of vibrations and its spectral contain and some of these applications exhibit a quite low frequency spectrum where harvesting surrounding mechanical energy make sense, typically 5-50Hz for implantable medical devices or 50Hz-150Hz for industrial machines. Harvesting such low frequency vibrations is a challenge since it leads to adapt the resonator geometries to the targeted frequency or to use out-off band indirect harvesting strategies. In this paper we present a piezoelectric based vibrational energy harvesting device (PEH) which could be integrated into a biocompatible package to power implantable sensor or therapeutic medical devices. The presented architecture is a serial bimorph laminated with ultra-thinned (ranging from 15μm to 100μm) outer PZT “skins” that could operate at a “very low frequency”, below 25Hz typically. The core process flow is disclosed and performances highlighted with regards to other low frequency demonstrations.

Powering autonomous sensors with miniaturized piezoelectric based energy harvesting devices operating at very low frequency

International Nuclear Information System (INIS)

Ferin, G; Bantignies, C; Khanh, H Le; Flesch, E; Nguyen-Dinh, A

2015-01-01

Harvesting energy from ambient mechanical vibrations is a smart and efficient way to power autonomous sensors and support innovative developments in IoT (Internet of Things), WSN (Wireless Sensor Network) and even implantable medical devices. Beyond the environmental operating conditions, efficiency of such devices is mainly related to energy source properties like the amplitude of vibrations and its spectral contain and some of these applications exhibit a quite low frequency spectrum where harvesting surrounding mechanical energy make sense, typically 5-50Hz for implantable medical devices or 50Hz-150Hz for industrial machines. Harvesting such low frequency vibrations is a challenge since it leads to adapt the resonator geometries to the targeted frequency or to use out-off band indirect harvesting strategies. In this paper we present a piezoelectric based vibrational energy harvesting device (PEH) which could be integrated into a biocompatible package to power implantable sensor or therapeutic medical devices. The presented architecture is a serial bimorph laminated with ultra-thinned (ranging from 15μm to 100μm) outer PZT “skins” that could operate at a “very low frequency”, below 25Hz typically. The core process flow is disclosed and performances highlighted with regards to other low frequency demonstrations. (paper)

Monitoring of fatigue damage in composite lap-joints using guided waves and FBG sensors

Science.gov (United States)

Karpenko, Oleksii; Khomenko, Anton; Koricho, Ermias; Haq, Mahmoodul; Udpa, Lalita

2016-02-01

Adhesive bonding is being increasingly employed in many applications as it offers possibility of light-weighting and efficient multi-material joining along with reduction in time and cost of manufacturing. However, failure initiation and progression in critical components like joints, specifically in fatigue loading is not well understood, which necessitates reliable NDE and SHM techniques to ensure structural integrity. In this work, concurrent guided wave (GW) and fiber Bragg grating (FBG) sensor measurements were used to monitor fatigue damage in adhesively bonded composite lap-joints. In the present set-up, one FBG sensor was strategically embedded in the adhesive bond-line of a lap-joint, while two other FBGs were bonded on the surface of the adherends. Full spectral responses of FBG sensors were collected and compared at specific intervals of fatigue loading. In parallel, guided waves were actuated and sensed using PZT wafers mounted on the composite adherends. Experimental results demonstrated that time-of-flight (ToF) of the fundamental modes transmitted through the bond-line and spectral response of FBG sensors were sensitive to fatigue loading and damage. Combination of guided wave and FBG measurements provided the desired redundancy and synergy in the data to evaluate the degradation in bond-line properties. Measurements taken in the presence of continuously applied load replicated the in-situ/service conditions. The approach shows promise in understanding the behavior of bonded joints subjected to complex loading.

Acousto-Optic Measurements in CFRP Laminates Using Fiber Bragg Grating Sensors

Science.gov (United States)

2011-09-01

light weight, high durability, corrosion resistance, high fatigue strength, and great design flexibility that are generating many areas of...instability in the laser produced an abundance of noise in our signal obtained from the FBG that wasn’t found in the PZT signal. Figure 3...comparable to that of the PZT [Figure 3]. Felicity Ratio Most of the loading procedures performed were such that they were intended to show

Effects of impurities on PZT ceramics

Energy Technology Data Exchange (ETDEWEB)

Song, Y J; Kim, H N

1982-01-01

The grain growth, dielectric constants, piezoelectric properties, and resistivity of Pb(Zr/sub 0.52/ Ti/sub 0.48/)+0.008La/sub 2/O/sub 3/ (or Nb/sub 2/.O/sub 5/)+xFe/sub 2/O/sub 3/ ceramics have been investigated as a function of Fe/sub 2/O/sub 3/ content. The grain size decreases up to 0.05 (or 0.1) mole % Fe/sub 2/O/sub 3/, but increases in the further region. This can be interpreted as such that the grain growth is not retarded by those impurities when the Fe/sub 2/O/sub 3/ content approaches the La/sub 2/O/sub 3/ (or Nb/sub 2/O/sub 5/) content because of the formation of La/sup 3 +/ (or Nb/sup 5 +/)-Fe/sup 3 +/ ion pairs. The dielectric constant has a maximum at 0.2 mole % Fe/sub 2/O/sub 3/ and decreases as the Fe/sub 2/O/sub 3/ content increases from that composition. The grain size effect is dominant in the variation of dielectric constant up 0.2 mole % Fe/sub 2/O/sub 3/. The resistivity of the ceramics of which the Fe/sub 2/O/sub 3/ content is 0.8 mole % shows the same tendency as that of the pure PZT ceramics, and it can be concluded that complete compensation of the donor and the acceptor has occurred.

Experimental investigation into the effect of substrate clamping on the piezoelectric behaviour of thick-film PZT elements

Energy Technology Data Exchange (ETDEWEB)

Torah, R N; Beeby, S P; White, N M [Department of Electronics and Computer Science, University of Southampton, SO17 1BJ (United Kingdom)

2004-04-07

This paper details an experimental investigation of the clamping effect associated with thick-film piezoelectric elements printed on a substrate. The clamping effect reduces the measured piezoelectric coefficient, d{sub 33}, of the film. This reduction is due to the influence of the d{sub 31} component in the film when a deformation of the structure occurs, by either the direct or indirect piezoelectric effect. Theoretical analysis shows a reduction in the measured d{sub 33} of 62%, i.e. a standard bulk lead zirconate titanate (PZT)-5H sample with a manufacturer specified d{sub 33} of 593pC/N would fall to 227.8pC/N. To confirm this effect, the d{sub 33} coefficients of five thin bulk PZT-5H samples of 220 {mu}m thickness were measured before and after their attachment to a metallized 96% alumina substrate. The experimental results show a reduction in d{sub 33} of 74% from 529pC/N to 139pC/N. The theoretical analysis was then applied to existing University of Southampton thick-film devices. It is estimated that the measured d{sub 33} value of 131pC/N of the thick-film devices is the equivalent of an unconstrained d{sub 33} of 345pC/N.

Temperature and driving field dependence of fatigue processes in PZT bulk ceramics

International Nuclear Information System (INIS)

Glaum, Julia; Granzow, Torsten; Schmitt, Ljubomira Ana; Kleebe, Hans-Joachim; Roedel, Juergen

2011-01-01

The temperature- and field-dependent degradation properties of bulk Pb(Zr,Ti)O 3 material (PZT) under a unipolar electric field were investigated. Unipolar cycling leads to the build-up of an internal bias field based on the agglomeration of charges at grain boundaries. A simple model was developed which describes the general dynamics of unipolar fatigue and its dependence on temperature and driving field. Comparing the large and small signal permittivity before and after fatigue led to the conclusion that domain walls became clamped by the agglomerated charges. This clamping effect could be visualized by transmission electron microscopy (TEM). Additionally, the TEM investigations revealed that unipolar fatigue leads to a weakening of the microstructure and to the development of microcracks.

One-Port Electronic Detection Strategies for Improving Sensitivity in Piezoelectric Resonant Sensor Measurements

Directory of Open Access Journals (Sweden)

Zhongxu Hu

2016-10-01

Full Text Available This paper describes a one-port mechanical resonance detection scheme utilized on a piezoelectric thin film driven silicon circular diaphragm resonator and discusses the limitations to such an approach in degenerate mode mass detection sensors. The sensor utilizes degenerated vibration modes of a radial symmetrical microstructure thereby providing both a sense and reference mode allowing for minimization of environmental effects on performance. The circular diaphragm resonator was fabricated with thickness of 4.5 µm and diameter of 140 µm. A PZT thin film of 0.75 µm was patterned on the top surface for the purposes of excitation and vibration sensing. The device showed a resonant frequency of 5.8 MHz for the (1, 1 mode. An electronic interface circuit was designed to cancel out the large static and parasitic capacitance allowing for electrical detection of the mechanical vibration thereby enabling the frequency split between the sense and reference mode to be measured accurately. The extracted motional current, proportional to the vibration velocity, was fed back to the drive to effectively increase the Q factor, and therefore device sensitivity, by more than a factor of 8. A software phase-locked loop was implemented to automatically track the resonant frequencies to allow for faster and accurate resonance detection. Results showed that by utilizing the absolute mode frequencies as an indication of sensor temperature, the variation in sensor temperature due to the heating from the drive electronics was accounted for and led to an ultimate measurement sensitivity of 2.3 Hz.

One-Port Electronic Detection Strategies for Improving Sensitivity in Piezoelectric Resonant Sensor Measurements

Science.gov (United States)

Hu, Zhongxu; Hedley, John; Keegan, Neil; Spoors, Julia; Gallacher, Barry; McNeil, Calum

2016-01-01

This paper describes a one-port mechanical resonance detection scheme utilized on a piezoelectric thin film driven silicon circular diaphragm resonator and discusses the limitations to such an approach in degenerate mode mass detection sensors. The sensor utilizes degenerated vibration modes of a radial symmetrical microstructure thereby providing both a sense and reference mode allowing for minimization of environmental effects on performance. The circular diaphragm resonator was fabricated with thickness of 4.5 µm and diameter of 140 µm. A PZT thin film of 0.75 µm was patterned on the top surface for the purposes of excitation and vibration sensing. The device showed a resonant frequency of 5.8 MHz for the (1, 1) mode. An electronic interface circuit was designed to cancel out the large static and parasitic capacitance allowing for electrical detection of the mechanical vibration thereby enabling the frequency split between the sense and reference mode to be measured accurately. The extracted motional current, proportional to the vibration velocity, was fed back to the drive to effectively increase the Q factor, and therefore device sensitivity, by more than a factor of 8. A software phase-locked loop was implemented to automatically track the resonant frequencies to allow for faster and accurate resonance detection. Results showed that by utilizing the absolute mode frequencies as an indication of sensor temperature, the variation in sensor temperature due to the heating from the drive electronics was accounted for and led to an ultimate measurement sensitivity of 2.3 Hz. PMID:27792154

Note: Resonance magnetoelectric interactions in laminate of FeCuNbSiB and multilayer piezoelectric stack for magnetic sensor

Science.gov (United States)

Li, Jianqiang; Lu, Caijiang; Xu, Changbao; Zhong, Ming

2015-09-01

This paper develops a simple miniature magnetoelectric (ME) laminate FeCuNbSiB/PZT-stack made up of magnetostrictive Fe73.5Cu1Nb3Si13.5B9 (FeCuNbSiB) foils and piezoelectric Pb(Zr, Ti)O3 (PZT) multilayer stack vibrator. Resonant ME interactions of FeCuNbSiB/PZT-stack with different layers of FeCuNbSiB foil (L) are investigated in detail. The experimental results show that the ME voltage coefficient reaches maximum value of 141.5 (V/cm Oe) for FeCuNbSiB/PZT-stack with L = 6. The AC-magnetic sensitivities can reach 524.29 mV/Oe and 1.8 mV/Oe under resonance 91.6 kHz and off-resonance 1 kHz, respectively. The FeCuNbSiB/PZT-stack can distinguish small dc-magnetic field of ˜9 nT. The results indicate that the proposed ME composites are very promising for the cheap room-temperature magnetic field sensing technology.

Structural and electrical properties of Sm{sup 3+} substituted PZT ceramics

Energy Technology Data Exchange (ETDEWEB)

Pandey, S.K. [Solid State Physics Laboratory, Timarpur, Delhi 110 054 (India)], E-mail: 628@ssplnet.org; Thakur, O.P.; Bhattacharya, D.K. [Solid State Physics Laboratory, Timarpur, Delhi 110 054 (India); Prakash, Chandra [DRDO Bhawan, DHQ, New Delhi 110 011 (India); Chatterjee, Ratnamala [Department of Physics, Indian Institute of Technology, New Delhi 110 016 (India)

2009-01-22

Samarium modified lead zirconate titanate (PSZT: Pb{sub 1-x}Sm{sub x}(Zr{sub 0.65}Ti{sub 0.35})O{sub 3}: x = 0, 0.02, 0.04, 0.06) ceramics were synthesized by solid state ceramic route. XRD shows single-phase formation with rhombohedral structure up to x = 0.04. With Sm-substitution, the grain size first increases up to x = 0.02 and then decreases. A metal/ferroelectric/metal (MFM) structure was made by depositing gold electrode on the flat surfaces for electrical measurements. All samples show normal ferroelectric behaviour, however, a squareness of P-E loop (polarization vs. electric field) was observed to increase with Sm content. Higher electromechanical coupling coefficients (K{sub p} and K{sub t}) have been achieved for the PZT with 6 mol% Sm substitution and having fine grain size.

Characterization And Operation Of PZT Ceramic Filters On Gamma-Radiation Environment

International Nuclear Information System (INIS)

Fawzy, Y.H.A.; Soliman, F.A.S.; Swidan, A.; Abdelmagid, A.

2008-01-01

The present paper deals with the gamma-ray effects on the electrical characteristics of ferroelectric materials used as an electronic frequency filters. After the recall of main observations, mechanisms are analyzed and proposed to take into account the effects in Lead- Zirconate-Titanate (PZT) based materials. In this concern, a wide frequency range samples, extends from 400 k Hz up to 6.5 MHz, were chosen for studying their frequency response and related terminologies, dynamic characteristics, and equivalent circuits. In general, for all samples, a shift on the frequency values was recorded, where the values of the center frequency, resonance frequency and anti-resonance frequency were shown to be shifted. The observed shift is mainly due to the noticed changes on the equivalent circuit elements of the devices, where a pronounced shift on the values of L,,,CP and R,, were recorded

Photoluminescence of sol–gel synthesized PZT powders

Energy Technology Data Exchange (ETDEWEB)

Rodríguez-Aranda, M.C. [Coordinación para la Innovación y Aplicación de la Ciencia y la Tecnología-Universidad Autónoma de San Luis Potosí, Av. Sierra Leona No.550,Col. Lomas 2a. sección, C.P. 78210 San Luis Potosí, SLP, México (Mexico); Calderón-Piñar, F. [Centro de Investigación y de Estudios Avanzados del I.P.N. Unidad Querétaro, Libramiento Norponiente No. 2000, Fracc. Real de Juriquilla, C.P. 7623 Querétaro, Qro, México (Mexico); Facultad de Física/IMRE, San Lázaro y L, Universidad de la Habana, C.P. 10400 Habana (Cuba); Hernández-Landaverde, M.A. [Centro de Investigación y de Estudios Avanzados del I.P.N. Unidad Querétaro, Libramiento Norponiente No. 2000, Fracc. Real de Juriquilla, C.P. 7623 Querétaro, Qro, México (Mexico); and others

2016-11-15

A wide band of photoluminescence (PL) emission in structurally disordered lead zirconate titanate (PZT) powders, prepared by sol–gel route, was observed at room temperature excited with a laser line (488 nm). Powders with PbZr{sub 0.53}Ti{sub 0.47}O{sub 3} nominal composition annealed at different temperatures were studied by X-ray diffraction, Raman spectroscopy, Luminescence, Diffuse Reflectance and Electronic Paramagnetic Resonance Spectroscopy (EPR). Our results indicate that the PL response can be associated to order–disorder degree in the perovskite structure, with the exception of samples annealed at low temperature, where a mixture of oxides precursorsГ—Ві phases was observed. Furthermore, in quasi-crystalline ordered samples (95% of crystallinity) a small generation of PL remains. In these experiments, the band gap increases with the formation of crystalline structure. EPR experiments were conducted in order to follow the evolution of paramagnetic species with thermal treatment from the mixture of oxides precursors to the perovskite phase and paramagnetic point defects were identified (Pb{sup +3} and Ti{sup +3}). EPR data suggest the presence of order–disorder within the lattice network. Paramagnetic species are similar in samples treated at 700 and 800 °C, nevertheless the emission intensity decreases by a factor of 6, indicating that the defects associated with PL are not paramagnetic at both temperatures.

Development of a real-time closed-loop micro-/nano-positioning system embedded with a capacitive sensor

International Nuclear Information System (INIS)

Shiou, Fang-Jung; Chiang, Chia-Jui; Liou, Ke-Jhen; Liao, Shu-Chung; Chen, Chao-Jung; Liou, Huay-Chung

2010-01-01

The hysteresis and nonlinearity of the PZT is an actual problem in the piezo-driven micro-/nano-positioning stage, especially for the open-loop positioning stage. The study presents the development of an NI cRIO9074-based real-time closed-loop micro-/nano-positioning system, to overcome the problem of the hysteresis and nonlinearity of a PZT and to increase the positioning speed of the positioning stage. The developed system mainly consists of a piezoelectric actuator, a bridge-type hinge mechanism for displacement magnification, a micro-/nano-positioning stage body, a capacitive sensor system, an NI cRIO9074 real-time control unit with FPGA chip and a PC. After executing the optimization analysis of the displacement, stress and the frequency, using the ANSYS software, the dimensions of the stage body have been designed and determined. A set of software written with the LabView programming language was developed to construct the real-time PID closed-loop control of the developed positioning system. Based on the test results, the designed closed-loop micro-/nano-positioning system was capable of precision positioning within the travel of 119.08 µm with maximum stage tilting angle at 25 µrad. The steady-state positioning deviation of the stage is about ±2 nm in the step-positioning test. In the transient slope-tracing test at a tracing speed of 5 µm s −1 , an error of about ±100 nm is observed

Fabrication of nano piezoelectric based vibration accelerometer for mechanical sensing

Science.gov (United States)

Murugan, S.; Prasad, M. V. N.; Jayakumar, K.

2016-05-01

An electromechanical sensor unit has been fabricated using nano PZT embedded in PVDF polymer. Such a polymer nano composite has been used as vibration sensor element and sensitivity, detection of mechanical vibration, and linearity measurements have been investigated. It is found from its performance, that this nano composite sensor is suitable for mechanical sensing applications.

Texture of poled tetragonal PZT detected by synchrotron X-ray diffraction and micromechanics analysis

International Nuclear Information System (INIS)

Hall, D.A.; Steuwer, A.; Cherdhirunkorn, B.; Withers, P.J.; Mori, T.

2005-01-01

The texture and lattice elastic strain due to electrical poling of tetragonal PZT (lead zirconate titanate) ceramics have been measured using high energy synchrotron X-ray diffraction. It is shown that XRD peak intensity ratios associated with crystal planes of the form {002}, {112} and {202} exhibit a linear dependence on cos-bar 2 Ψ, where Ψ represents the orientation angle between the plane normal and the macroscopic poling axis. The observed dependence of texture and lattice strain on the grain orientation can be understood on the basis that the macroscopic strain due to poling is the average of the poling strains of all the individual grains

Influence of irradiation on the switching behavior in PZT thin films

International Nuclear Information System (INIS)

Baturin, I.; Menou, N.; Shur, V.; Muller, C.; Kuznetsov, D.; Hodeau, J.-L.; Sternberg, A.

2005-01-01

Spatially nonuniform imprint behavior induced by X-ray synchrotron, electron and neutron irradiation has been investigated in sol-gel Pb(Zr,Ti)O 3 thin films. The analysis of the switching current data reveals the strong influence of irradiation on the switching current shape. The obtained effects have been explained as a result of acceleration of the bulk screening process induced by irradiation. It was shown that the spatial distribution of the internal bias field is determined by the domain structure existing during irradiation. The changes in the structural characteristics during fatigue cycling have been reveled by high resolution synchrotron X-ray diffraction experiments on (1 1 1)-oriented PZT-based capacitors with a composition in the morphotropic region. From both ex situ and in situ measurements, microstructural changes with cyclic switching during fatigue have been evidenced and correlated with the evolution of the switching characteristics

Wafer-scale growth of highly textured piezoelectric thin films by pulsed laser deposition for micro-scale sensors and actuators

Science.gov (United States)

Nguyen, M. D.; Tiggelaar, R.; Aukes, T.; Rijnders, G.; Roelof, G.

2017-11-01

Piezoelectric lead-zirconate-titanate (PZT) thin films were deposited on 4-inch (111)Pt/Ti/SiO2/Si(001) wafers using large-area pulsed laser deposition (PLD). This study was focused on the homogeneity in film thickness, microstructure, ferroelectric and piezoelectric properties of PZT thin films. The results indicated that the highly textured (001)-oriented PZT thin films with wafer-scale thickness homogeneity (990 nm ± 0.8%) were obtained. The films were fabricated into piezoelectric cantilevers through a MEMS microfabrication process. The measured longitudinal piezoelectric coefficient (d 33f = 210 pm/V ± 1.6%) and piezoelectric transverse coefficient (e 31f = -18.8 C/m2 ± 2.8%) were high and homogeneity across wafers. The high piezoelectric properties on Si wafers will extend industrial application of PZT thin films and further development of piezoMEMS.

Estimation of strain from piezoelectric effect and domain switching in morphotropic PZT by combined analysis of macroscopic strain measurements and synchrotron X-ray data

International Nuclear Information System (INIS)

Kungl, Hans; Theissmann, Ralf; Knapp, Michael; Baehtz, Carsten; Fuess, Hartmut; Wagner, Susanne; Fett, Theo; Hoffmann, Michael J.

2007-01-01

Morphotropic PZT ceramics are State of the art materials for ferroelectric actuators. Essential performance parameters for these materials are strain and hysteresis. On a microscopic scale the strain provided by an electric field is due to two different mechanisms. The piezoelectric effect causes an elongation of the unit cells, whereas domain switching changes their crystallographic orientation by aligning the polarization axis towards the field direction. A method is outlined to estimate the contribution of the two mechanisms to total strain by combining macroscopic strain measurements and X-ray diffraction (XRD) data. Results from macroscopic measurements of remanent and unipolar strain with the corresponding data on texture, derived from in situ synchrotron radiation XRD patterns, are analyzed and evaluated by a semi-empirical approach. The method was applied to six morphotropic, LaSr doped PZT materials of different Zr/Ti ratios. Results are discussed with respect to the differences between the materials

Fabrication of In(0.75)Zn(1.5)Sn(1.0) (IZTO) Thin-Film Transistors Using Solution-Processable Materials and PZT Inkjet-Printing.

Science.gov (United States)

Lee, Tai-Kuang; Liuand, Chao-Te; Lee, Wen-Hsi

2017-01-01

Recently, Thin Film Transistors (TFTs) have been studied widely because of potential applications in low cost, low-temperature process and flexible displays. They can be fabricated by easy processes based on solution methods. But the mobility of organic TFTs is lower and the threshold voltage is higher than amorphous Si TFTs. In order to enhance the channel mobility and satisfy with the requirement of low-cost fabrication, we prepare a low-cost, mask-free, reduced material wastage, deposited technology using transparent, directly printable, air-stable semiconductor slurries and dielectric solutions. In our investigations, we attempt to obtain a high performance and low-cost TFT via preparing materials, designing device structure, and using PZT inkjet-printing technology. A stable and non-precipitated metal oxide ink with appropriate doping was prepared for the fabrication of an InxZn1.5Sn1.0 (IZTO) by PZT inkjet-printing. The soluble direct-printing process is a powerful tool for material research and implies that the printable materials and the printing technology enable the use of all-printed low-cost flexible displays and other transparent electronic applications. Transparent materials including dielectric PVP, conductive carbon nanotube (CNT) and active IZTO were employed into the fabrication of our PZT inkjet-printing process. After annealed at 180 °C, The experimental all-printed TFT exhibit the carrier mobility of 0.194 cm2/Vs, sub-threshold slope of 20 V/decade, and the threshold voltage of 5 V, initially. All-inkjet-printed films have great transparency, potentially in transparent electronics and the transmittance pattern in visible part of the spectrum (400–700 nm) is over 80%.

Feasibility of using PZT actuators to study the dynamic behavior of a rotating disk due to rotor-stator interaction.

Science.gov (United States)

Presas, Alexandre; Egusquiza, Eduard; Valero, Carme; Valentin, David; Seidel, Ulrich

2014-07-07

In this paper, PZT actuators are used to study the dynamic behavior of a rotating disk structure due to rotor-stator interaction excitation. The disk is studied with two different surrounding fluids-air and water. The study has been performed analytically and validated experimentally. For the theoretical analysis, the natural frequencies and the associated mode shapes of the rotating disk in air and water are obtained with the Kirchhoff-Love thin plate theory coupled with the interaction with the surrounding fluid. A model for the Rotor Stator Interaction that occurs in many rotating disk-like parts of turbomachinery such as compressors, hydraulic runners or alternators is presented. The dynamic behavior of the rotating disk due to this excitation is deduced. For the experimental analysis a test rig has been developed. It consists of a stainless steel disk (r = 198 mm and h = 8 mm) connected to a variable speed motor. Excitation and response are measured from the rotating system. For the rotating excitation four piezoelectric patches have been used. Calibrating the piezoelectric patches in amplitude and phase, different rotating excitation patterns are applied on the rotating disk in air and in water. Results show the feasibility of using PZT to control the response of the disk due to a rotor-stator interaction.

Feasibility of Using PZT Actuators to Study the Dynamic Behavior of a Rotating Disk due to Rotor-Stator Interaction

Directory of Open Access Journals (Sweden)

Alexandre Presas

2014-07-01

Full Text Available In this paper, PZT actuators are used to study the dynamic behavior of a rotating disk structure due to rotor-stator interaction excitation. The disk is studied with two different surrounding fluids—air and water. The study has been performed analytically and validated experimentally. For the theoretical analysis, the natural frequencies and the associated mode shapes of the rotating disk in air and water are obtained with the Kirchhoff-Love thin plate theory coupled with the interaction with the surrounding fluid. A model for the Rotor Stator Interaction that occurs in many rotating disk-like parts of turbomachinery such as compressors, hydraulic runners or alternators is presented. The dynamic behavior of the rotating disk due to this excitation is deduced. For the experimental analysis a test rig has been developed. It consists of a stainless steel disk (r = 198 mm and h = 8 mm connected to a variable speed motor. Excitation and response are measured from the rotating system. For the rotating excitation four piezoelectric patches have been used. Calibrating the piezoelectric patches in amplitude and phase, different rotating excitation patterns are applied on the rotating disk in air and in water. Results show the feasibility of using PZT to control the response of the disk due to a rotor-stator interaction.

Novel ferroelectric capacitor for non-volatile memory storage and biomedical tactile sensor applications

International Nuclear Information System (INIS)

Liu, Shi Yang; Chua, Lynn; Tan, Kian Chuan; Valavan, S.E.

2010-01-01

We report on novel ferroelectric thin film compositions for use in non-volatile memory storage and biomedical tactile sensor applications. The lead zirconate titanate (PZT) composition was modified by lanthanum (La 3+ ) (PLZT) and vanadium (V 5+ ) (PZTV, PLZTV) doping. Hybrid films with PZTV and PLZTV as top layers are also made using seed layers of differing compositions using sol-gel and spin coating methods. La 3+ doping decreased the coercive field, polarization and leakage current, while increasing the relative permittivity. V 5+ doping, while having similar effects, results in an enhanced polarization, with comparable dielectric loss characteristics. Complex doping of both La 3+ and V 5+ in PLZTV, while reducing the polarization relative to PZTV, significantly decreases the coercive field. Hybrid films have a greater uniformity of grain formation than non-hybrid films, thus decreasing the coercive field, leakage current and polarization fatigue while increasing the relative permittivity. Analysis using X-ray diffraction (XRD) verified the retention of the PZT perovskite structure in the novel films. PLZT/PZTV has been identified as an optimal ferroelectric film composition due to its desirable ferroelectric, fatigue and dielectric properties, including the highest observed remnant polarization (P r ) of ∼ 25 μC/cm 2 , saturation polarization (P sat ) of ∼ 58 μC/cm 2 and low coercive field (E c ) of ∼ 60 kV/cm at an applied field of ∼ 1000 kV/cm, as well as a low leakage current density of ∼ 10 -5 A/cm 2 at 500 kV/cm and fatigue resistance of up to ∼ 10 10 switching cycles.

Micro-particle manipulation by single beam acoustic tweezers based on hydrothermal PZT thick film.

Science.gov (United States)

Zhu, Benpeng; Xu, Jiong; Li, Ying; Wang, Tian; Xiong, Ke; Lee, Changyang; Yang, Xiaofei; Shiiba, Michihisa; Takeuchi, Shinichi; Zhou, Qifa; Shung, K Kirk

2016-03-01

Single-beam acoustic tweezers (SBAT), used in laboratory-on-a-chip (LOC) device has promising implications for an individual micro-particle contactless manipulation. In this study, a freestanding hydrothermal PZT thick film with excellent piezoelectric property (d 33 = 270pC/N and k t = 0.51) was employed for SBAT applications and a press-focusing technology was introduced. The obtained SBAT, acting at an operational frequency of 50MHz, a low f-number (∼0.9), demonstrated the capability to trap and manipulate a micro-particle sized 10μm in the distilled water. These results suggest that such a device has great potential as a manipulator for a wide range of biomedical and chemical science applications.

Electrical excitation and optical detection of ultrasounds in PZT based piezoelectric transducers

Energy Technology Data Exchange (ETDEWEB)

Babilotte, P; Diallo, O; Hue, L-P Tran Hu; Feuillard, G [University Francois Rabelais de Tours, Laboratory Imaging and Brain, Team Ultrasonic Characterisation and Piezoelectricity, ENIVL, Rue de la Chocolaterie, 41034 BLOIS CEDEX (France); Kosec, M; Kuscer, D, E-mail: philippe.babilotte@univ-tours.fr [Josef Stefan Institute, Jamova cesta 39, 1000 LJUBLJANA (Slovenia)

2011-01-01

The displacement response of piezoelectric PZT thick films fabricated by means of electrophoretic deposition and laid down an alumina substrate is investigated using coherent optical detection. According to thickness properties determined by electrical impedance measurements, the film presents a resonance around 40 MHz. Other resonance peaks are observed that correspond to eigen modes of the film substrate couple structure. Uniformity of the response of the integrated structure is studied across the surface of the sample when excited by either a continuous or impulse electrical voltage. Results on the amplitude of the detected signal versus the frequency and the input excitation voltage are reported. The optical detection used in these experiments is complementary to conventional techniques of characterization of piezoelectric devices such as electrical impedance measurements and allows getting information on the displacement response of the device.

Very early age concrete hydration characterization monitoring using piezoceramic based smart aggregates

International Nuclear Information System (INIS)

Kong, Qingzhao; Song, Gangbing; Hou, Shuang; Ji, Qing; Mo, Y L

2013-01-01

Very early age (0–20 h) concrete hydration is a complicated chemical reaction. During the very early age period, the concrete condition dramatically changes from liquid state to solid state. This paper presents the authors’ recent research on monitoring very early age concrete hydration characterization by using piezoceramic based smart aggregates. The smart aggregate (SA) transducer is designed as a sandwich structure using two marble blocks and a pre-soldered lead zirconate titanate (PZT) patch. Based on the electromechanical property of piezo materials, the PZT patches function as both actuators and sensors. In addition, the marble blocks provide reliable protection to the fragile PZT patch and develop the SA into a robust embedded actuator or sensor in the structure. The active-sensing approach, which involved a pair of smart aggregates with one as an actuator and the other one as a sensor, was applied in this paper’s experimental investigation of concrete hydration characterization monitoring. In order to completely understand the hydration condition of the inhomogeneous, over-cluttering, high-scattering characteristics of concrete (specifically of very early concrete), a swept sine wave and several constant frequency sine waves were chosen and produced by a function generator to excite the embedded actuating smart aggregate. The PZT vibration induced ultrasonic wave propagated through the concrete and was sent to the other smart aggregate sensor. The electrical signal transferred from the smart aggregate sensor was recorded during the test. As the concrete hydration reaction was occurring, the characteristic of the electrical signal continuously changed. This paper describes the successful investigation of the three states (the fluid state, the transition state, and the hardened state) of very early age concrete hydration based on classification of the received electrical signal. Specifically, the amplitude and frequency response of the electrical

Filmes finos de LaNiO3 e PZT preparados pelo métodos das soluções precursoras poliméricas e depositados em substratos de silício

OpenAIRE

Souza, Éder Carlos Ferreira de [UNESP

2006-01-01

Nesta tese estudou-se a preparação de filmes finos de PZT não dopados e dopados com Nióbio, depositados sobre substratos de Pt/Ti/SiO2/Si para aplicações em memórias não voláteis de acesso randômico (NVRAM) e memórias ferroelétricas de acesso randômico (FeRAM). A dopagem dos filmes de PZT com Nióbio foi realizada visando obter valores ótimos nas propriedades ferroelétricas para a aplicação destes filmes como memórias ferroelétricas. Todavia, problemas como imprint, corrente de fuga e fadiga n...

Analyzing the defect structure of CuO-doped PZT and KNN piezoelectrics from electron paramagnetic resonance.

Science.gov (United States)

Jakes, Peter; Kungl, Hans; Schierholz, Roland; Eichel, Rüdiger-A

2014-09-01

The defect structure for copper-doped sodium potassium niobate (KNN) ferroelectrics has been analyzed with respect to its defect structure. In particular, the interplay between the mutually compensating dimeric (Cu(Nb)'''-V(O)··) and trimeric (V(O)··-Cu(Nb)'''-V(O)··)· defect complexes with 180° and non-180° domain walls has been analyzed and compared to the effects from (Cu'' - V(O)··)(x)× dipoles in CuO-doped lead zirconate titanate (PZT). Attempts are made to relate the rearrangement of defect complexes to macroscopic electromechanical properties.

Determination of temperature dependence of full matrix material constants of PZT-8 piezoceramics using only one sample.

Science.gov (United States)

Zhang, Yang; Tang, Liguo; Tian, Hua; Wang, Jiyang; Cao, Wenwu; Zhang, Zhongwu

2017-08-15

Resonant ultrasound spectroscopy (RUS) was used to determine the temperature dependence of full matrix material constants of PZT-8 piezoceramics from room temperature to 100 °C. Property variations from sample to samples can be eliminated by using only one sample, so that data self-consistency can be guaranteed. The RUS measurement system error was estimated to be lower than 2.35%. The obtained full matrix material constants at different temperatures all have excellent self-consistency, which can help accurately predict device performance at high temperatures using finite element simulations.

Quantitative Diagnostics of Multilayered Composite Structures with Ultrasonic Guided Waves

Science.gov (United States)

2014-09-01

sensors. These IDT sensors were fabricated from thin wafer of piezoelectric lead zirconate titanate ( PZT ) substrates by using a pulse laser micro...pavement structures," J. Acoust. Soc. Am., vol. 116, no. 5, pp. 2902-2913, 2004. [9] E. Kostson and P. Fromme, " Fatigue crack growth monitoring in multi

Residual stress and Young's modulus of pulsed laser deposited PZT thin films: Effect of thin film composition and crystal direction of Si cantilevers

NARCIS (Netherlands)

Nazeer, H.; Nguyen, Duc Minh; Rijnders, Augustinus J.H.M.; Abelmann, Leon; Sardan Sukas, Ö.

2016-01-01

We investigated the residual stress and Young's modulus of Pb(ZrxTi1 - x)O3 (PZT) thin films with a (110) preferred orientation and a composition x ranging from 0.2 to 0.8. The films are grown by pulsed laser deposition on silicon cantilevers aligned along the <110> and <100> silicon crystal

A Sensor Data Fusion System Based on k-Nearest Neighbor Pattern Classification for Structural Health Monitoring Applications

Directory of Open Access Journals (Sweden)

Jaime Vitola

2017-02-01

Full Text Available Civil and military structures are susceptible and vulnerable to damage due to the environmental and operational conditions. Therefore, the implementation of technology to provide robust solutions in damage identification (by using signals acquired directly from the structure is a requirement to reduce operational and maintenance costs. In this sense, the use of sensors permanently attached to the structures has demonstrated a great versatility and benefit since the inspection system can be automated. This automation is carried out with signal processing tasks with the aim of a pattern recognition analysis. This work presents the detailed description of a structural health monitoring (SHM system based on the use of a piezoelectric (PZT active system. The SHM system includes: (i the use of a piezoelectric sensor network to excite the structure and collect the measured dynamic response, in several actuation phases; (ii data organization; (iii advanced signal processing techniques to define the feature vectors; and finally; (iv the nearest neighbor algorithm as a machine learning approach to classify different kinds of damage. A description of the experimental setup, the experimental validation and a discussion of the results from two different structures are included and analyzed.

Micro-particle manipulation by single beam acoustic tweezers based on hydrothermal PZT thick film

Directory of Open Access Journals (Sweden)

Benpeng Zhu

2016-03-01

Full Text Available Single-beam acoustic tweezers (SBAT, used in laboratory-on-a-chip (LOC device has promising implications for an individual micro-particle contactless manipulation. In this study, a freestanding hydrothermal PZT thick film with excellent piezoelectric property (d33 = 270pC/N and kt = 0.51 was employed for SBAT applications and a press-focusing technology was introduced. The obtained SBAT, acting at an operational frequency of 50MHz, a low f-number (∼0.9, demonstrated the capability to trap and manipulate a micro-particle sized 10μm in the distilled water. These results suggest that such a device has great potential as a manipulator for a wide range of biomedical and chemical science applications.

Micro-particle manipulation by single beam acoustic tweezers based on hydrothermal PZT thick film

Energy Technology Data Exchange (ETDEWEB)

Zhu, Benpeng, E-mail: benpengzhu@hust.edu.cn [School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074 (China); State Key Laboratory of Transducer Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Xu, Jiong; Yang, Xiaofei [School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074 (China); Li, Ying; Lee, Changyang; Zhou, Qifa; Shung, K. Kirk [Department of Biomedical Engineering and NIH Transducer Resource Center, University of Southern California, Los Angeles, California 90089-1111 (United States); Wang, Tian; Xiong, Ke [Department of Physics and Key Laboratory of Acoustic and Photonic Materials and Devices of Ministry of Education, Wuhan University, Wuhan 430072 (China); Shiiba, Michihisa; Takeuchi, Shinichi [Medical Engineering Course, Graduate School of Engineering, Toin University of Yokohama, Yokohama 225-8501 (Japan)

2016-03-15

Single-beam acoustic tweezers (SBAT), used in laboratory-on-a-chip (LOC) device has promising implications for an individual micro-particle contactless manipulation. In this study, a freestanding hydrothermal PZT thick film with excellent piezoelectric property (d{sub 33} = 270 pC/N and k{sub t} = 0.51) was employed for SBAT applications and a press-focusing technology was introduced. The obtained SBAT, acting at an operational frequency of 50 MHz, a low f-number (∼0.9), demonstrated the capability to trap and manipulate a micro-particle sized 10μm in the distilled water. These results suggest that such a device has great potential as a manipulator for a wide range of biomedical and chemical science applications.

Using the methods of radiospectroscopy (EPR, NMR) to study the nature of the defect structure of solid solutions based on lead zirconate titanate (PZT)

Czech Academy of Sciences Publication Activity Database

Bykov, I. P.; Zagorodniy, A.Y.; Yurchenko, L.P.; Korduban, A.M.; Nejezchleb, K.; Trachevsky, V.V.; Dimza, V.; Jastrabík, Lubomír; Dejneka, Alexandr

2014-01-01

Roč. 61, č. 8 (2014), 1379-1385 ISSN 0885-3010 R&D Projects: GA TA ČR TA01010517; GA ČR GAP108/12/1941 Institutional support: RVO:68378271 Keywords : lead zirconate titanate ( PZT ) * EPR * NMR * XPS spectroscopy Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.512, year: 2014

Elastic and anelastic relaxation behaviour of perovskite multiferroics II: PbZr0.53Ti0.47O3 (PZT)-PbFe0.5Ta0.5O3 (PFT).

Science.gov (United States)

Schiemer, J A; Lascu, I; Harrison, R J; Kumar, A; Katiyar, R S; Sanchez, D A; Ortega, N; Mejia, C Salazar; Schnelle, W; Shinohara, H; Heap, A J F; Nagaratnam, R; Dutton, S E; Scott, J F; Nair, B; Mathur, N D; Carpenter, M A

2017-01-01

Elastic and anelastic properties of ceramic samples of multiferroic perovskites with nominal compositions across the binary join PbZr 0.53 Ti 0.47 O 3 -PbFe 0.5 Ta 0.5 O 3 (PZT-PFT) have been assembled to create a binary phase diagram and to address the role of strain relaxation associated with their phase transitions. Structural relationships are similar to those observed previously for PbZr 0.53 Ti 0.47 O 3 -PbFe 0.5 Nb 0.5 O 3 (PZT-PFN), but the magnitude of the tetragonal shear strain associated with the ferroelectric order parameter appears to be much smaller. This leads to relaxor character for the development of ferroelectric properties in the end member PbFe 0.5 Ta 0.5 O 3 . As for PZT-PFN, there appear to be two discrete instabilities rather than simply a reorientation of the electric dipole in the transition sequence cubic-tetragonal-monoclinic, and the second transition has characteristics typical of an improper ferroelastic. At intermediate compositions, the ferroelastic microstructure has strain heterogeneities on a mesoscopic length scale and, probably, also on a microscopic scale. This results in a wide anelastic freezing interval for strain-related defects rather than the freezing of discrete twin walls that would occur in a conventional ferroelastic material. In PFT, however, the acoustic loss behaviour more nearly resembles that due to freezing of conventional ferroelastic twin walls. Precursor softening of the shear modulus in both PFT and PFN does not fit with a Vogel-Fulcher description, but in PFT there is a temperature interval where the softening conforms to a power law suggestive of the role of fluctuations of the order parameter with dispersion along one branch of the Brillouin zone. Magnetic ordering appears to be coupled only weakly with a volume strain and not with shear strain but, as with multiferroic PZT-PFN perovskites, takes place within crystals which have significant strain heterogeneities on different length scales.

Direct Intracochlear Acoustic Stimulation Using a PZT Microactuator.

Science.gov (United States)

Luo, Chuan; Omelchenko, Irina; Manson, Robert; Robbins, Carol; Oesterle, Elizabeth C; Cao, Guo Zhong; Shen, I Y; Hume, Clifford R

2015-12-01

Combined electric and acoustic stimulation has proven to be an effective strategy to improve hearing in some cochlear implant users. We describe an acoustic microactuator to directly deliver stimuli to the perilymph in the scala tympani. The 800 µm by 800 µm actuator has a silicon diaphragm driven by a piezoelectric thin film (e.g., lead-zirconium-titanium oxide or PZT). This device could also be used as a component of a bimodal acoustic-electric electrode array. In the current study, we established a guinea pig model to test the actuator for its ability to deliver auditory signals to the cochlea in vivo. The actuator was placed through the round window of the cochlea. Auditory brainstem response (ABR) thresholds, peak latencies, and amplitude growth were calculated for an ear canal speaker versus the intracochlear actuator for tone burst stimuli at 4, 8, 16, and 24 kHz. An ABR was obtained after removal of the probe to assess loss of hearing related to the procedure. In some animals, the temporal bone was harvested for histologic analysis of cochlear damage. We show that the device is capable of stimulating ABRs in vivo with latencies and growth functions comparable to stimulation in the ear canal. Further experiments will be necessary to evaluate the efficiency and safety of this modality in long-term auditory stimulation and its ability to be integrated with conventional cochlear implant arrays. © The Author(s) 2015.

Direct Intracochlear Acoustic Stimulation Using a PZT Microactuator

Directory of Open Access Journals (Sweden)

Chuan Luo

2015-11-01

Full Text Available Combined electric and acoustic stimulation has proven to be an effective strategy to improve hearing in some cochlear implant users. We describe an acoustic microactuator to directly deliver stimuli to the perilymph in the scala tympani. The 800 µm by 800 µm actuator has a silicon diaphragm driven by a piezoelectric thin film (e.g., lead-zirconium-titanium oxide or PZT. This device could also be used as a component of a bimodal acoustic-electric electrode array. In the current study, we established a guinea pig model to test the actuator for its ability to deliver auditory signals to the cochlea in vivo. The actuator was placed through the round window of the cochlea. Auditory brainstem response (ABR thresholds, peak latencies, and amplitude growth were calculated for an ear canal speaker versus the intracochlear actuator for tone burst stimuli at 4, 8, 16, and 24 kHz. An ABR was obtained after removal of the probe to assess loss of hearing related to the procedure. In some animals, the temporal bone was harvested for histologic analysis of cochlear damage. We show that the device is capable of stimulating ABRs in vivo with latencies and growth functions comparable to stimulation in the ear canal. Further experiments will be necessary to evaluate the efficiency and safety of this modality in long-term auditory stimulation and its ability to be integrated with conventional cochlear implant arrays.

Effects of atmosphere in sintering pure or doped PZT with barium and strontium ions; Efeito da atmosfera na sinterizacao do PZT puro ou dopado com ions bario e estroncio

Energy Technology Data Exchange (ETDEWEB)

Simoes, A.Z.; D`Alkimin, R.; Zaghete, M.A.; Perazolli, L.; Varela, J.A.; Gimenes, E.R. [UNESP, Araraquara, SP (Brazil). Inst. de Quimica

1996-05-01

Lead zirconate titanate powder with Zr/Ti ratio of 50/50 was prepared by Pechini method and doped with 1,0; 3,0 and 5,0 mol% of Ba or Sr ions. The powder was calcined at 700 deg C by 3 hours and milled by 6 hours in isopropyl alcohol. Surface area was measured by BET method and the purity of the powder characterized by IV. DRX was used to characterize the crystal structure. The powder was isostatically pressed at 230 MPa and sintered in a dilatometer furnace with constant heating rate of 10 deg C/min up to 1100 deg C. Argon, synthetic air oxygen and oxygen with water vapor were used at atmosphere. The presence of Ba or Sr ions reduce the temperature of maximum sintering rate for all considered atmospheres. The effects of each sintering atmosphere of doped PZT is discussed. (author) 6 refs., 3 figs., 2 tabs.

Damage detection in concrete structures with smart piezoceramic transducers

Science.gov (United States)

Naidu, Akshay S. K.; Bhalla, Suresh

2003-10-01

Detection of damages and progressive deterioration in structures is a critical issue. Visual inspections are tedious and unreliable. Incipient damages are often not discernible by low frequency dynamic response and other NDE techniques. Smart piezoelectric ceramic (PZT) transducers are emerging as an effective alternative in health monitoring of structures. The electro-mechanical impedance method employs the self-actuating and sensing characteristics of the PZT, without having to use actuators and sensors separately. When excited by an ac source, the PZT transducers bonded to the host structure activates the higher modes of vibration locally. Changes in the admittance response of the transducer serves as an indicator of damage around the transducer. In this paper, the effectiveness of PZT transducers for characterizing damages in concrete, in terms of the damage extent and location, is experimentally examined. The root mean square deviation (RMSD) index, adopted to quantify the changes in the admittance signatures, correlates with the damage extent. The damages on the surface that is not mounted by the PZT are also discernible. An array of transducers proves effective in detecting the damaged zone. The progressive incipient crack can be detected much before it actually becomes visible to the naked eye.

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

Science.gov (United States)

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, θ x , θ y ) 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 μ m 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 μ m 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 μ m, which approaches the desired imaging resolution, 5 μ m, 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.

5 V Compatible Two-Axis PZT Driven MEMS Scanning Mirror with Mechanical Leverage Structure for Miniature LiDAR Application.

Science.gov (United States)

Ye, Liangchen; Zhang, Gaofei; You, Zheng

2017-03-05

The MEMS (Micro-Electronical Mechanical System) scanning mirror is an optical MEMS device that can scan laser beams across one or two dimensions. MEMS scanning mirrors can be applied in a variety of applications, such as laser display, bio-medical imaging and Light Detection and Ranging (LiDAR). These commercial applications have recently created a great demand for low-driving-voltage and low-power MEMS mirrors. However, no reported two-axis MEMS scanning mirror is available for usage in a universal supplying voltage such as 5 V. In this paper, we present an ultra-low voltage driven two-axis MEMS scanning mirror which is 5 V compatible. In order to realize low voltage and low power, a two-axis MEMS scanning mirror with mechanical leverage driven by PZT (Lead zirconate titanate) ceramic is designed, modeled, fabricated and characterized. To further decrease the power of the MEMS scanning mirror, a new method of impedance matching for PZT ceramic driven by a two-frequency mixed signal is established. As experimental results show, this MEMS scanning mirror reaches a two-axis scanning angle of 41.9° × 40.3° at a total driving voltage of 4.2 Vpp and total power of 16 mW. The effective diameter of reflection of the mirror is 2 mm and the operating frequencies of two-axis scanning are 947.51 Hz and 1464.66 Hz, respectively.

Design and implementation of a versatile and variable-frequency piezoelectric coefficient measurement system.

Science.gov (United States)

Wu, J S; Huang, Y K; Wu, F L; Lin, D Y

2012-08-01

We present a simple but versatile piezoelectric coefficient measurement system, which can measure the longitudinal and transverse piezoelectric coefficients in the pressing and bending modes, respectively, at different applied forces and a wide range of frequencies. The functionality of this measurement system has been demonstrated on three samples, including a PbZr(0.52)Ti(0.48)O(3) (PZT) piezoelectric ceramic bulk, a ZnO thin film, and a laminated piezoelectric film sensor. The static longitudinal piezoelectric coefficients of the PZT bulk and the ZnO film are estimated to be around 210 and 8.1 pC/N, respectively. The static transverse piezoelectric coefficients of the ZnO film and the piezoelectric film sensor are determined to be, respectively, -0.284 and -0.031 C/m(2).

Effect of the Crystal Structure on the Electrical Properties of Thin-Film PZT Structures

Science.gov (United States)

Delimova, L. A.; Gushchina, E. V.; Zaitseva, N. V.; Seregin, D. S.; Vorotilov, K. A.; Sigov, A. S.

2018-03-01

A new method of two-stage crystallization of lead zirconate-titanate (PZT) films using a seed sublayer with a low excess lead content has been proposed and realized. A seed layer with a strong texture of perovskite Pe(111) grains is formed from a solution with a lead excess of 0-5 wt %; the fast growth of the grains is provided by the deposition of the main film from a solution with high lead content. As a result, a strong Pe(111) texture with complete suppression of the Pe(100) orientation forms. An analysis of current-voltage dependences of the transient currents and the distributions of the local conductivity measured by the contact AFM method reveals two various mechanisms of current percolation that are determined by traps in the bulk and at the perovskite grain interfaces.

Vibration energy harvesting in railway tunnels with a wireless sensor node application

Energy Technology Data Exchange (ETDEWEB)

Wischke, Martin

2012-07-01

Vibration harvesting is a promising concept to prolong the lifetime of batterypowered stand-alone systems, or even to enable their energy-autonomy. This thesis focuses on ambient vibrations converted by electromechanical transducers into electricity. The final goal is energy scavenging from train-induced vibrations in railway tunnels. This is achieved via the development of a suitable harvester for this environment and the practical demonstration of a vibrationpowered wireless sensor node (WSN). At the beginning of this thesis, extensive vibration measurements were performed in several traffic tunnels. The obtained unique data set formed the basis for the design and test of several harvesters. The railway sleeper was chosen as usable harvester location. A shock-resistant double-side suspended piezoelectric cantilever was developed. Several cantilevers with different eigenfrequencies are combined in an array, creating a robust harvester with a broad bandwidth. A field test of 7 days in the Loetschbergbasis-tunnel verified that, on average the sufficient energy for powering a virtual wireless sensor node was scavenged. For application in a real WSN, the harvester array was scaled up to 10 cantilevers. The power management for the sensor node was developed concurrently. The central component is a power switch that monitors the energy level in the system's storage capacitor and only triggers the wireless interface when sufficient energy is available. Combined with a train detection circuit, the presented energy-autonomous WSN reliably reports every passing vehicle. In addition to the development of an energy-autonomous fully integrated WSN, this work investigates nonlinear properties of PZT ceramics. Consideration of the elastostriction and the electrostriction enables a more precises prediction of the tip displacement of a piezoelectric cantilever actuator. Further, the elastostriction is exploited to modify the resonance frequency of a bimorph cantilever. Basing

Microfabrication and integration of a sol-gel PZT folded spring energy harvester.

Science.gov (United States)

Lueke, Jonathan; Badr, Ahmed; Lou, Edmond; Moussa, Walied A

2015-05-26

This paper presents the methodology and challenges experienced in the microfabrication, packaging, and integration of a fixed-fixed folded spring piezoelectric energy harvester. A variety of challenges were overcome in the fabrication of the energy harvesters, such as the diagnosis and rectification of sol-gel PZT film quality and adhesion issues. A packaging and integration methodology was developed to allow for the characterizing the harvesters under a base vibration. The conditioning circuitry developed allowed for a complete energy harvesting system, consisting a harvester, a voltage doubler, a voltage regulator and a NiMH battery. A feasibility study was undertaken with the designed conditioning circuitry to determine the effect of the input parameters on the overall performance of the circuit. It was found that the maximum efficiency does not correlate to the maximum charging current supplied to the battery. The efficiency and charging current must be balanced to achieve a high output and a reasonable output current. The development of the complete energy harvesting system allows for the direct integration of the energy harvesting technology into existing power management schemes for wireless sensing.

Distributed Piezoelectric Sensor System for Damage Identification in Structures Subjected to Temperature Changes

Directory of Open Access Journals (Sweden)

Jaime Vitola

2017-05-01

Full Text Available Structural health monitoring (SHM is a very important area in a wide spectrum of fields and engineering applications. With an SHM system, it is possible to reduce the number of non-necessary inspection tasks, the associated risk and the maintenance cost in a wide range of structures during their lifetime. One of the problems in the detection and classification of damage are the constant changes in the operational and environmental conditions. Small changes of these conditions can be considered by the SHM system as damage even though the structure is healthy. Several applications for monitoring of structures have been developed and reported in the literature, and some of them include temperature compensation techniques. In real applications, however, digital processing technologies have proven their value by: (i offering a very interesting way to acquire information from the structures under test; (ii applying methodologies to provide a robust analysis; and (iii performing a damage identification with a practical useful accuracy. This work shows the implementation of an SHM system based on the use of piezoelectric (PZT sensors for inspecting a structure subjected to temperature changes. The methodology includes the use of multivariate analysis, sensor data fusion and machine learning approaches. The methodology is tested and evaluated with aluminum and composite structures that are subjected to temperature variations. Results show that damage can be detected and classified in all of the cases in spite of the temperature changes.

Distributed Piezoelectric Sensor System for Damage Identification in Structures Subjected to Temperature Changes.

Science.gov (United States)

Vitola, Jaime; Pozo, Francesc; Tibaduiza, Diego A; Anaya, Maribel

2017-05-31

Structural health monitoring (SHM) is a very important area in a wide spectrum of fields and engineering applications. With an SHM system, it is possible to reduce the number of non-necessary inspection tasks, the associated risk and the maintenance cost in a wide range of structures during their lifetime. One of the problems in the detection and classification of damage are the constant changes in the operational and environmental conditions. Small changes of these conditions can be considered by the SHM system as damage even though the structure is healthy. Several applications for monitoring of structures have been developed and reported in the literature, and some of them include temperature compensation techniques. In real applications, however, digital processing technologies have proven their value by: (i) offering a very interesting way to acquire information from the structures under test; (ii) applying methodologies to provide a robust analysis; and (iii) performing a damage identification with a practical useful accuracy. This work shows the implementation of an SHM system based on the use of piezoelectric (PZT) sensors for inspecting a structure subjected to temperature changes. The methodology includes the use of multivariate analysis, sensor data fusion and machine learning approaches. The methodology is tested and evaluated with aluminum and composite structures that are subjected to temperature variations. Results show that damage can be detected and classified in all of the cases in spite of the temperature changes.

Size effects on structural and dielectric properties of PZT thin films at compositions around the morpho tropic phase boundary

International Nuclear Information System (INIS)

Lima, Elton Carvalho; Araujo, Eudes Borges; Souza Filho, Antonio Gomes de; Bdikin, Igor

2011-01-01

Full text: The demand for portability in consumer electronics has motivated the understanding of size effects on ferroelectric thin films. The actual comprehension of these effects in ferroelectrics is unsatisfactory, since the polarization interacts more strongly than other order parameters such as strain and charge. As a result, extrinsic effects are produced if these variables are uncontrolled and problems such as ferroelectric paraelectric phase transition at nanometers scale remains an unsolved issue. In the present work, the effects of thickness and compositional fractions on the structural and dielectric properties of PbZr 1-x Ti x O 3 (PZT) thin films were studied at a composition around the morphotropic phase boundary (x = 0.50). For this purpose, thin films with different thicknesses and different PbO excess were deposited on Si(100) and Pt=T iO 2 =SiO 2 =Si substrates by a chemical method and crystallized in electric furnace at 700 deg C for 1 hour. The effects of substrate, pyrolysis temperature and excess lead addition in the films are reported. For films with 10 mol% PbO in excess, the pyrolysis in the regime of 300 deg C for 30 minutes was observed to yield PZT pyrochlore free thin films deposited on Pt=T iO 2 =SiO 2 =Si substrate. Out this condition, the transformation from amorphous to the pyrochlore metastable phase is kinetically more favorable that a transformation to the perovskite phase, which is thermodynamically stable. Rietveld refinements based on X-ray diffraction results showed that films present a purely tetragonal phase and that this phase does not change when the film thickness decreases. The dielectric permittivity measurements showed a monoclinic → tetragonal phase transition at 198K. Results showed that the dielectric permittivity (ε) increases continuously from 257 to 463, while the thickness of the PZT films increases from 200 to 710 nm. These results suggests that interface pinning centers can be the responsible mechanism by

Pb(Zr,Ti)O3-Pb(Mn1/3Nb2/3)O3 piezoelectric thick films by aerosol deposition

International Nuclear Information System (INIS)

Ryu, Jungho; Choi, Jong-Jin; Hahn, Byung-Dong; Yoon, Woon-Ha; Lee, Byoung-Kuk; Choi, Joon Hwan; Park, Dong-Soo

2010-01-01

Piezoelectric thick films of Pb(Zr,Ti)O 3 -Pb(Mn 1/3 Nb 2/3 )O 3 (PZT-PMnN) with Zr:Ti ratios ranging from 0.45:0.55 to 0.60:0.40 were fabricated on a platinized silicon wafer by aerosol deposition (AD). All the films were deposited with a thickness of 10 μm with high density. By adding PMnN to 57:43 PZT, a dielectric constant as low as ∼660 was achieved while the effective piezoelectric constant was over 140 pC/N. PZT-PMnN with a Zr:Ti ratio of 57:43 thus showed a maximum piezoelectric voltage constant (g 33 ) of 23.8 x 10 -3 Vm/N and is a good candidate for high quality thick films for application to high-energy density or high sensitivity, piezoelectric energy harvesters and sensors.

The performance of integrated active fiber composites in carbon fiber laminates

International Nuclear Information System (INIS)

Melnykowycz, M; Brunner, A J

2011-01-01

Piezoelectric elements integrated into fiber-reinforced polymer-matrix laminates can provide various functions in the resulting adaptive or smart composite. Active fiber composites (AFC) composed of lead zirconate titanate (PZT) fibers can be used as a component in a smart material system, and can be easily integrated into woven composites. However, the impact of integration on the device and its functionality has not been fully investigated. The current work focuses on the integration and performance of AFC integrated into carbon-fiber-reinforced plastic (CFRP) laminates, focusing on the strain sensor performance of the AFC–CFRP laminate under tensile loading conditions. AFC were integrated into cross-ply CFRP laminates using simple insertion and interlacing of the CFRP plies, with the AFC always placed in the 90° ply cutout area. Test specimens were strained to different strain levels and then cycled with a 0.01% strain amplitude, and the resulting signal from the AFC was monitored. Acoustic emission monitoring was performed during tensile testing to provide insight to the failure characteristics of the PZT fibers. The results were compared to those from past studies on AFC integration; the strain signal of AFC integrated into CFRP was much lower than that for AFC integrated into woven glass fiber laminates. However, the profiles of the degradations of the AFC signal resulting from the strain were nearly identical, showing that the PZT fibers fragmented in a similar manner for a given global strain. The sensor performance recovered upon unloading, which is attributed to the closure of cracks between PZT fiber fragments

Impedance Based Characterization of a High-Coupled Screen Printed PZT Thick Film Unimorph Energy Harvester

DEFF Research Database (Denmark)

Lei, Anders; Xu, R.; Borregaard, L. M.

2014-01-01

The single degree of freedom mass-spring-damper system is the most common approach for deriving a full electromechanical model for the piezoelectric vibration energy harvester. In this paper, we revisit this standard electromechanical model by focusing on the impedance of the piezoelectric device...... parameters which, by means of the piezoelectric impedance expression, all can be determined accurately by electrical measurements. It is shown how four of five lumped parameters can be determined from a single impedance measurement scan, considerably reducing the characterization effort. The remaining...... parameter is determined from shaker measurements, and a highly accurate agreement is found between model and measurements on a unimorph MEMS-based screen printed PZT harvester. With a high coupling term K-2 Q similar or equal to 7, the harvester exhibits two optimum load points. The peak power performance...

Active Vibration Suppression of a 3-DOF Flexible Parallel Manipulator Using Efficient Modal Control

Directory of Open Access Journals (Sweden)

Quan Zhang

2014-01-01

Full Text Available This paper addresses the dynamic modeling and efficient modal control of a planar parallel manipulator (PPM with three flexible linkages actuated by linear ultrasonic motors (LUSM. To achieve active vibration control, multiple lead zirconate titanate (PZT transducers are mounted on the flexible links as vibration sensors and actuators. Based on Lagrange’s equations, the dynamic model of the flexible links is derived with the dynamics of PZT actuators incorporated. Using the assumed mode method (AMM, the elastic motion of the flexible links are discretized under the assumptions of pinned-free boundary conditions, and the assumed mode shapes are validated through experimental modal test. Efficient modal control (EMC, in which the feedback forces in different modes are determined according to the vibration amplitude or energy of their own, is employed to control the PZT actuators to realize active vibration suppression. Modal filters are developed to extract the modal displacements and velocities from the vibration sensors. Numerical simulation and vibration control experiments are conducted to verify the proposed dynamic model and controller. The results show that the EMC method has the capability of suppressing multimode vibration simultaneously, and both the structural and residual vibrations of the flexible links are effectively suppressed using EMC approach.

Edge geometry effects on resonance response of electroplated cylindrical Ni/PZT/Ni magnetoelectric composites

Science.gov (United States)

Yakubov, Vladislav; Xu, Lirong; Volinsky, Alex A.; Qiao, Lijie; Pan, De'an

2017-08-01

Trilayer Ni/PZT/Ni cylindrical magnetoelectric (ME) composites were prepared by electrodeposition, a process, which creates sub-millimeter raised edges due to current concentration near sharp points. The ME response in both axial and vertical modes was measured with the edges, with only outer edges removed, and with both outer and inner edges removed. The ME voltage coefficient improved at resonance by 40% and 147% without the edges in the vertical and axial modes, respectively. The observed improvements in three different samples were only present at the ME resonance and no changes were detected outside of the ME resonance. Mechanical quality factor at resonance also improved with no effect on the resonant frequency. Experimentally demonstrated minor geometry changes resulted in substantial ME improvement at resonant frequency. This study demonstrates device performance optimization. The observed effects have been attributed to improved vibrations in terms of decreased damping coefficient and enhanced vibration amplitude at resonance.

Edge geometry effects on resonance response of electroplated cylindrical Ni/PZT/Ni magnetoelectric composites

Directory of Open Access Journals (Sweden)

Vladislav Yakubov

2017-08-01

Full Text Available Trilayer Ni/PZT/Ni cylindrical magnetoelectric (ME composites were prepared by electrodeposition, a process, which creates sub-millimeter raised edges due to current concentration near sharp points. The ME response in both axial and vertical modes was measured with the edges, with only outer edges removed, and with both outer and inner edges removed. The ME voltage coefficient improved at resonance by 40% and 147% without the edges in the vertical and axial modes, respectively. The observed improvements in three different samples were only present at the ME resonance and no changes were detected outside of the ME resonance. Mechanical quality factor at resonance also improved with no effect on the resonant frequency. Experimentally demonstrated minor geometry changes resulted in substantial ME improvement at resonant frequency. This study demonstrates device performance optimization. The observed effects have been attributed to improved vibrations in terms of decreased damping coefficient and enhanced vibration amplitude at resonance.

Piezoelectric Lead Zirconate Titanate (PZT) Ring Shaped Contour-Mode MEMS Resonators

Science.gov (United States)

Kasambe, P. V.; Asgaonkar, V. V.; Bangera, A. D.; Lokre, A. S.; Rathod, S. S.; Bhoir, D. V.

2018-02-01

Flexibility in setting fundamental frequency of resonator independent of its motional resistance is one of the desired criteria in micro-electromechanical (MEMS) resonator design. It is observed that ring-shaped piezoelectric contour-mode MEMS resonators satisfy this design criterion than in case of rectangular plate MEMS resonators. Also ring-shaped contour-mode piezoelectric MEMS resonator has an advantage that its fundamental frequency is defined by in-plane dimensions, but they show variation of fundamental frequency with different Platinum (Pt) thickness referred as change in ratio of fNEW /fO . This paper presents the effects of variation in geometrical parameters and change in piezoelectric material on the resonant frequencies of Platinum piezoelectric-Aluminium ring-shaped contour-mode MEMS resonators and its electrical parameters. The proposed structure with Lead Zirconate Titanate (PZT) as the piezoelectric material was observed to be a piezoelectric material with minimal change in fundamental resonant frequency due to Platinum thickness variation. This structure was also found to exhibit extremely low motional resistance of 0.03 Ω as compared to the 31-35 Ω range obtained when using AlN as the piezoelectric material. CoventorWare 10 is used for the design, simulation and corresponding analysis of resonators which is Finite Element Method (FEM) analysis and design tool for MEMS devices.

Analysis of Piezoelectric Structural Sensors with Emergent Computing Techniques

Science.gov (United States)

Ramers, Douglas L.

2005-01-01

The purpose of this project was to try to interpret the results of some tests that were performed earlier this year and to demonstrate a possible use of emergence in computing to solve IVHM problems. The test data used was collected with piezoelectric sensors to detect mechanical changes in structures. This project team was included of Dr. Doug Ramers and Dr. Abdul Jallob of the Summer Faculty Fellowship Program, Arnaldo Colon-Lopez - a student intern from the University of Puerto Rico of Turabo, and John Lassister and Bob Engberg of the Structural and Dynamics Test Group. The tests were performed by Bob Engberg to compare the performance two types of piezoelectric (piezo) sensors, Pb(Zr(sub 1-1)Ti(sub x))O3, which we will label PZT, and Pb(Zn(sub 1/3)Nb(sub 2/3))O3-PbTiO, which we will label SCP. The tests were conducted under varying temperature and pressure conditions. One set of tests was done by varying water pressure inside an aluminum liner covered with carbon-fiber composite layers (a cylindrical "bottle" with domed ends) and the other by varying temperatures down to cryogenic levels on some specially prepared composite panels. This report discusses the data from the pressure study. The study of the temperature results was not completed in time for this report. The particular sensing done with these piezo sensors is accomplished by the sensor generating an controlled vibration that is transmitted into the structure to which the sensor is attached, and the same sensor then responding to the induced vibration of the structure. There is a relationship between the mechanical impedance of the structure and the resulting electrical impedance produced in the in the piezo sensor. The impedance is also a function of the excitation frequency. Changes in the real part of impendance signature relative to an original reference signature indicate a change in the coupled structure that could be the results of damage or strain. The water pressure tests were conducted by

Microfabrication and Integration of a Sol-Gel PZT Folded Spring Energy Harvester