Type PZT Research Articles

Structural model and scheme of a piezoengine for aeronautics and aerospace

In the work the structural model and the structural scheme of a piezoengine are calculated for aeronautics and aerospace. The matrix equation of a piezoactuator is determined. The mechanical characteristic and the parameters of the PZT piezoactuator are obtained in control systems for aeronautics and aerospace. A piezoengine is used for nanoalignment and nanopositioning, compensation of temperature and gravitational deformations in aeronautics and aerospace, nanoresearh for tunel microscopy, adaptive optics, astronomy for compound telescope and satellite telescope. The linear change in the size of a piezoengine occurs by the electric field changes. A piezoengine is a piezomechanical device for converting electrical energy into mechanical energy and for actuating mechanisms, systems or its controlling by using inverse piezoeeffect. Piezoceramics include barium titanate or ferroelectric ceramics, based on lead zirconate titanate type PZT, are widely used for the production of piezoengines. The PZT piezoengine is characterized by high accuracy, small overall dimensions, simple design and control, reliability and cost effectiveness. The structural general model, the scheme and the functions a piezoengine are obtained for aeronautics and aerospace. Method of applied mathematical physics is applied for determinations the characteristics of a piezoengine with using the piezoelasticity equation and the differential equation. The static and dynamic characteristics of the PZT piezoengine are determined.

Lead zirconate titanate aerogel composite coatings with lightweight structure, excellent mechanical and integrated electrical properties for underwater acoustic transducers

Lead zirconate titanate (PZT) aerogels are ideal piezoelectric materials for underwater acoustic transducers (UATs) due to their light structure, but their difficult preparation, poor mechanical properties and poor integrated electrical properties greatly limit their practical applications. In order to overcome these difficulties, we innovatively adopted a solvothermally combined sol-gel method to successfully achieve simple, rapid, and low-cost preparation of PZT aerogels, designed a 0–3 type PZT aerogel/PVDF composite coating to overcome the weak mechanical properties of PZT aerogels, and used SiO2 aerogels and PZT ceramic powders to improve the ferroelectric and piezoelectric properties of the PZT aerogel/PVDF composite coating, respectively. After verifying that the PZT aerogel/PVDF composite coating modified by 4 wt% SiO2 aerogels and 30 wt% PZT ceramic powders has the best integrated electrical properties, we prepared its 50-layer combination to further improve the comprehensive properties. The 50-layer composite coating has a moderate piezoelectric constant d33 of 132.7 pC/N and a high piezoelectric constant d31 of −33.6 pC/N, a low relative permittivity of 593.7 and a low dielectric loss of 0.85% at 40 Hz, a high Young's modulus of 616.2 MPa, and a density of 1.163 g/cm3 similar to water, indicating that it has surpassed various high-performance Pb-containing piezoelectric ceramics in integrated electrical properties, mechanical properties and acoustic impedance matching with water, which is more in line with the needs of use in UATs. This research offers a new pathway to design a piezoelectric material for UATs with light structure and excellent comprehensive properties.

Microstructure and Piezoelectric Properties of Lead Zirconate Titanate Nanocomposites Reinforced with In-Situ Formed ZrO2 Nanoparticles.

Lead zirconate titanate (PZT)-based ceramics are used in numerous advanced applications, including sensors, displays, actuators, resonators, chips; however, the poor mechanical characteristics of these materials severely limits their utility in composite materials. To address this issue, we herein fabricate transgranular type PZT ceramic nanocomposites by a novel method. Thermodynamically metastable single perovskite-type Pb0.99(Zr0.52+xTi0.48)0.98Nb0.02O3+1.96x powders are prepared from a citrate precursor before both monoclinic and tetragonal ZrO2 nanoparticles ranging from 20 to 80 nm are precipitated in situ at a sintering temperature of 1260 °C. The effects of ZrO2 content on the microstructure, dielectric, and piezoelectric properties are investigated and the mechanism, by which ZrO2 toughened PZT is analyzed in detail. The ZrO2 nanoparticles underwent a tetragonal to monoclinic phase transition upon cooling. The fracture mode changed from intergranular to transgranular with increasing ZrO2 content. The incorporation of ZrO2 nanoparticles improved the mechanical and piezoelectric properties. The optimized piezoelectric properties (εT33/ε0 = 1398, tan δ = 0.024 d33 = 354 pC N−1, kp = 0.66 Qm = 78) are obtained when x = 0.02. Tc initially increased and subsequently decreased with increasing ZrO2 content. The highest Tc = (387 °C) and lowest εT33/ε0 was obtained at x = 0.01.

2P5-3 Vibration characteristic analysis according to thickness of support layer of diaphragm type PZT resonator

2P5-3 Vibration characteristic analysis according to thickness of support layer of diaphragm type PZT resonator

Detection of Debonding Between Fiber Reinforced Polymer Bar and Concrete Structure Using Piezoceramic Transducers and Wavelet Packet Analysis

Fiber reinforced polymer (FRP), a composite material with high corrosion resistance and high strength-to-weight ratio, has been increasingly used in reinforced concrete structures. The effectiveness of the structures depends on the bonding behavior between FRP composites and concrete structures. Therefore, detection of the debonding between the FRP materials and the hosting concrete structure is of great importance to ensure the structural safety. This paper proposes a stress wave-based active sensing approach to monitor the debonding process of FRP bar with the hosting concrete structure. One shear-type lead zirconate titanate (PZT) patch bonded on the outer surface of the FRP bar was used as an actuator to generate stress wave. Two smart aggregates (SAs), which were fabricated by sandwiching a shear type PZT patch between two protection marble pieces, were embedded in the hosting concrete structure to detect the wave response. The occurrence of debonding between the FRP bar and the hosting concrete structure attenuates the wave propagation. An FRP bar reinforced concrete specimen was designed and fabricated in laboratory. A pullout test was conducted to simulate different degrees of debonding damage. The attenuation of the stress wave due to debonding was clearly observed from the signal received by SAs in both time and frequency domain. Furthermore, a damage index based on wavelet packet analysis was developed to evaluate the debonding status. Experimental results demonstrate that the proposed method has potentials to detect different degrees of debonding damage of FRP bar reinforced concrete composite structures.

Effects of slurry composition on the properties of 3-1 type porous PZT ceramics prepared by ionotropic gelation

In this study, 3-1 type lead zirconate titanate (PZT) ceramics with one-dimensional pore channels were produced by ionotropic gelation process of alginate/PZT suspensions. By increasing the sodium alginate concentration from 1.0wt% to 3.0wt%, the alginate/PZT suspensions turned from Newtonian to non-Newtonian behavior with substantial increase in apparent viscosity. Accordingly, 3-1 type PZT ceramics with porosity decreasing from 56.78% to 41.44% were obtained, while the pore size distribution became non-uniform gradually. Based on the structural features, the 3-1 type PZT ceramics possessed much higher relative permittivity (εr) than that of 3-0 or 3-3 type PZT ceramics with similar porosities. Increase in the porosity led to a moderate decline in the longitudinal piezoelectric strain coefficient (d33), a reduction in the dielectric loss factor (tan δ), and a high value of hydrostatic strain coefficient (dh). As a result, the 3-1 type PZT ceramics possessed a maximal hydrostatic figure of merit (HFOM) value of 5597×10–15Pa−1 when the porosity was 56.78%, which may be of help for low frequency hydrophones applications.

Elaboration and dielectric characterization of a doped ferroelectric material type PZT

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 ABO 3 . We are interested to study the Quaternary system (doping in site A and site B) of general formula: Pb 0.96 Ba 0.02 Ca 0.02 [(Zr 0.52 Ti 0.48 ) 0.94 (Zn 1/3 Ta 2/3 ) 0.03 (In 1/3 Sb 2/3 ) 0.03 ]O 3 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 er = 18018, low dielectric loss: tgδ = 7.62%, for the composition sintered to 1180 ° C included in the phase morphotropique zone (FMP). Keywords: Ceramics PZT, Dielectric properties, Dielectric constant / loss constant.

Preparation and properties of 3–1 type PZT ceramics by a self-organization method

In this work, 3–1 type PZT ceramics with unidirectionally aligned channels have been fabricated by ionotropic gelation process of alginate/PZT suspensions. The 3-1 type PZT ceramics with porosity ranging from 36.9% to 60.6% were fabricated by adjusting the initial solid loading (5–25 wt%) of slurries. By incorporating CaO into PZT matrix during the process, the relative permittivity of porous ceramics was reduced, which was beneficial for enhancing the value of hydrostatic figure of merit (HFOM). With regard to the piezoelectric and mechanical properties, due to the combination of highly ordered capillary structure and doping of CaO, 3–1 type PZT ceramics demonstrated excellent performances. As a result, the prepared samples possessed a maximal HFOM value of 7.6×10−12Pa−1 and compressive strength of 125MPa. The acoustic impedance (Z) of specimens decreased linearly with increasing porosity, making them promising candidates for application to underwater sonar or medical imaging.

Model of piezoelectric self powered supply for wearable devices

With the development in a few latter years, of micros electromechanical technology (MEMS), the demand in wearable electronics and in cordless detectors is more and more important. These wearable devices have needed more of autonomy and independence in energy. Materials piezoelectric (often called intelligent materials) can be employed like mechanisms to convert the mechanical energy, due to vibration usually ambient, in energy electric. This one can be stored and used in place of conventional battery which presents certain disadvantages such as lasted limited life as well as congestion.In this article, one presents a power analytical model generated by a smart structure of type PZT that can be used as supply energy for electronic device. This model allows the determination of suitable sizes and vibration levels of piezoelectric material for to generate an optimal energy supply for a mobile phone. Two types of vibration mode have been compared as a function of characteristics and piezoelectric ceramic sizes.

Contribution to the study of the coexistence of phases tetragonal-rhombohedral in ceramic type PZT and general form: Pb [ZrxTi0,95-x(Mo1/3In2/3)0.05]O3

Pb[ZrxTi0,95-x(Mo1/3In2/3)0.05]O3 piezoelectric ceramics with varying Zr/Ti ratio were prepared by the conventional method of thermal synthesis of mixed-oxides.the samples structures was determined by X-ray diffractometry to demonstrate the co-existence of the tetragonal and rhombohedral phases. In the present system the MPB, in which the tetragonal and rhombohedral phases coexist, is in a composition range of 0.47≤x≤0.50. The lattice constants of the a and c axes for the samples caculeted from the XRD patterns. Microstructure of the sintered ceramics was observed by scanning electron microscopy (SEM) using free surfaces of the specimens.

Horn Geometry Effects on Atomization Characteristics of a Micro Nozzle Array Type Ultrasonic Fuel Injector

Effects of horn geometry on the atomization characteristics of an ultrasonic fuel injector using a micro nozzle array were investigated experimentally. Micro nozzles whose exit diameter d=3μm are mounted on a thin metal film. The number of the micro nozzles is from 2.0×104 to 1.2×105. Using an ultrasonic oscillator, gasoline is periodically pushed out from the micro nozzles at a frequency from 62 to 65 kHz. A disk type PZT is used as an ultrasonic oscillator, and the oscillation is amplified using a step-type horn. The input voltage to the PZT is varied from 0 to 200 V. To increase the fuel flow rate, the horn small end diameter Ds is increased from 10.5 to 25 mm, while the large end diameter is fixed at 30 mm. To prevent forming a liquid film on the micro nozzle array, gutters are machined on the small end of the horn. It is shown that the SMD (Sauter mean diameter) of the spray is almost uniform around 10 to 14μm, regardless of the horn small end diameter. The fuel flow rate increases, at the maximum, 2.8 times larger when compared to the original horn geometry.

PRESSURE CONTROL CHARACTERISTICS OF ELECTRO-PNEUMATIC REGULATOR WITH TWO MULTILAYERED PZT VALUES

This paper presents pressure control method using the electro-pneumatic regulator with two multilayered PZT valves. An electro-pneumatic regulator is a type of pressure control valve that is a combination of a poppet valve for main pressure control, two multilayered PZT valves for pilot pressure control, a microprocessor with a feedback controller and a pressure sensor. The benefits of bender type PZT actuator are faster response times, low energy consumption, and the ability to be used in hazardous environments and field bus systems. Solenoid actuator for electro-pneumatic regulator is widely used but this actuator has a high power consumption characteristics. So PZT actuator is required for the energy saving. In this study, a multilayered bender type PZT actuator of 27.0 mm(L)×9.0 mm(W)×0.8 (mm) with a constant of 220e-12 m/V and 20 sheets of PZT thin film was fabricated and experimented. The experiments for On-Off control and PID-PWM control of the electro-pneumatic regulator were operated under the input condition of 0.5 MPa. From the experiments, the performance characteristics of the fabricated electro-pneumatic regulator were evaluated. A new control method for precise proportional pressure control using the electro-pneumatic regulator with two PZT valves was suggested. Using this suggested model, all possible operating conditions were analyzed.

Uniplexing and Multiplexing of PZT Transducers for Structural Health Monitoring

Piezoceramic (PZT) transducers are extensively used in structural health monitoring (SHM) and noise and vibration control (NVC) of various aero, civil, and mechanical (ACM) structures. They are surface bonded on the host structure and are excited to produce structural responses. These responses form the basis of PZT—structure interaction based SHM or NVC methods. The last couple of decades have seen many `single input single output' (SISO) type PZT—structure interaction models. However, researchers are compelled to study `multiple input multiple output' (MIMO) or `multiple input single output' (MISO) type PZT—structure interaction models in addition to the SISO models to deal with ACM structures. Multiplexing is a process of active excitation and extraction of output responses from multiple PZT transducers, whereas uniplexing is active excitation and extraction of output response from a single PZT in the presence of other passive distributed transducers. Thus, this article focuses on the experimental study of such MISO/MIMO based multiplexing of PZT transducers, together with SISO based uniplexing on a prototype plate structure. This study also highlights the problems of interference due to transducers during uniplexing/ multiplexing and their influence on output responses.

Long Range Inspection of Wall Reduction of Tank Utilizing Zero-th Order Symmetric Mode Lamb Wave —Performance Demonstration of the Method Proposed—

We developed a new long range inspection method of corrosion-induced wall reduction of storage tanks. The method utilizes the zero-th order symmetric mode (So-mode) Lamb waves excited and monitored by a specially designed rectangular compression type PZT transducer mounted on the edge of the annular plate and side wall. The system can measure both the location and damage depth from the arrival time and amplitude of the So-mode reflected by the defects, respectively. We first measured attenuation of the So-mode wave and then the depth of dishshaped wall reduction on single carbon steel plate. Amplitude of the So-mode wave reflected by the defects was found to increase proportionally with the defect depth less than 15% of the plate thickness (10 mm). Amplitude of the reflected So-mode Lamb wave from the shallow dishshaped defects with depth of 0.6 mm or 7.5% to the plate thickness was detected. We also detected the So-mode waves from corrosion-induced dish-shaped wall reduction with 1.45 mm depth in 10 mm plate. Artificial groove of 1 mm depth on the step-weld 8 mm plates could be detected by the proposed method. [doi:10.2320/matertrans.I-MRA2007843]

Dynamical Nonlinearities in Piezoelectric Materials

AbstractDynamical nonlinearities in piezoelectric materials have been investigated over different time and frequency scales using four different methods; measurements of displacement and electric polarization of bulk material, measurements of nanometer scale surface structure of the material by an atomic force microscope (AFM), and numerical modelling of ferroelectric materials with quenched randomness. Laser vibrometer measurements of the deformations of piezoelectric materials, d31 type PZT and PMN-PT sheets, have been done under sinusoidal voltage loading with different frequencies. This yields information about the dynamical hysteresis behavior, such as the area of the hysteresis loops as a function of the applied frequency f and voltage amplitude. Similarly the hysteresis loops have been measured for the electric polarization of the same samples. Relaxation behaviors of the same materials have been measured by an AFM. Topography of the piezo sheets was measured after applied DC voltage, indicating slow collective changes in the polarization close and at the sample surface. To investigate the time-dependent hysteresis, we have studied numerically a Ginzburg-Landau-Devonshire (GLD) model for ferroelectric materials including dilution type quenched randomness. Quantities studied include the area of the hysteresis loop, of the polarization in the material, and the coercive electric field Ec as a function of the frequency f, both as a function of the disorder strength.

DEVELOPMENT OF A NEW UTM (UNIVERSAL TESTING MACHINE) SYSTEM FOR THE NANO/MICRO IN-PROCESS MEASUREMENT

Micro UTM (Universal Testing Machines) are becoming increasingly popular for testing the mechanical properties of MEMS materials, metal thin films, and micro-molecule materials1-2. And, new miniature testing machines that can perform in-process measurement in SEM, TEM, and SPM are also needed. In this paper, a new micro UTM with a precision positioning system that can be fine positioning stage. Coarse positioning is implemented by step motor. The size, load output and used in SEM, TEM, and SPM have been proposed. Bimorph type PZT precision actuator is used in displacement output of bimorph type UTM are 109×64×22( mm ), about 35g, and 0.4 mm, respectively. And the displacement output is controlled in the block digital form. The results of the analysis and basic properties of positioning system and the UTM system are presented. In addition, the experiment results of in-process measurement during tensile load in SEM and AFM are showed.

Resonance Modes in the Standard Characterization of Ferro-Piezoceramic Samples: A Discussion Based on Modelling by Finite Element Analysis

Among the methods for the complex characterization of piezoceramics from complex impedance measurements at resonance, Alemany et al. developed an automatic iterative method, applied to the four modes of resonance needed for the purpose of the determination of the full set of complex elastic, dielectric and piezoelectric coefficients in the linear range of poled piezoceramics, 6 mm symmetry materials. This complex characterization allows the Finite Element Analysis of the standard sample geometries used. The comparison of the experimental resonance spectra and the results obtained for elastically, dielectrically and piezoelectrically homogeneous item of a Navy II type PZT based commercial piezoceramic is here presented and discussed.

Health monitoring and rehabilitation of a concrete structure using intelligentmaterials

This paper presents the concept of an intelligent reinforced concrete structure (IRCS) andits application in structural health monitoring and rehabilitation. The IRCS hasmultiple functions which include self-rehabilitation, self-vibration damping, andself-structural health monitoring. These functions are enabled by two types ofintelligent (smart) materials: shape memory alloys (SMAs) and piezoceramics. In thisresearch, Nitinol type SMA and PZT (lead zirconate titanate) type piezoceramics areused. The proposed concrete structure is reinforced by martensite Nitinol cablesusing the method of post-tensioning. The martensite SMA significantly increasesthe concrete’s damping property and its ability to handle large impact. In thepresence of cracks due to explosions or earthquakes, by electrically heating the SMAcables, the SMA cables contract and close up the cracks. In this research, PZTpatches are embedded in the concrete structure to detect possible cracks insidethe concrete structure. The wavelet packet analysis method is then applied as asignal-processing tool to analyze the sensor signals. A damage index is defined todescribe the damage severity for health monitoring purposes. In addition, bymonitoring the electric resistance change of the SMA cables, the crack widthcan be estimated. To demonstrate this concept, a concrete beam specimen withreinforced SMA cables and with embedded PZT patches is fabricated. Experimentsdemonstrate that the IRC has the ability of self-sensing and self-rehabilitation.Three-point bending tests were conducted. During the loading process, a crack opensup to 0.47 inches. Upon removal of the load and heating the SMA cables, thecrack closes up. The damage index formed by wavelet packet analysis of the PZTsensor data predicts and confirms the onset and severity of the crack during theloading. Also during the loading, the electrical resistance value of the SMA cablechanges by up to 27% and this phenomenon is used to monitor the crack width.

P3-65 Vibration and Welding Characteristics of a 27 kHz Complex Vibration Source Using Longitudinal vibration disk and Six Bolt-clamped Langevin Type PZT Transducers(Poster session 3)

P3-65 Vibration and Welding Characteristics of a 27 kHz Complex Vibration Source Using Longitudinal vibration disk and Six Bolt-clamped Langevin Type PZT Transducers(Poster session 3)

P3-63 Vibration and Welding Characteristics of a 27 kHz Complex Vibration Source Using a (2,1) Transverse Vibration Disk and Six Bolt-clamped Langevin Type PZT transducers(Poster session 3)

P3-63 Vibration and Welding Characteristics of a 27 kHz Complex Vibration Source Using a (2,1) Transverse Vibration Disk and Six Bolt-clamped Langevin Type PZT transducers(Poster session 3)