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Showing 1 to 17 of 17 for “"Piezoelectric Ceramics"”.
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Domain Switching and Microcracking in Ferroelectric Single Crystals and Polycrystalline Ceramics
In polycrystalline piezoelectric ceramics, electric field-induced cracking occurred by intergranular fracture. The macroscopic path of the crack growth depended strongly upon the applied field and the poling direction. Analysis showed that cracks extended along the place of maximum normal strain. …
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Micromechanics of piezocomposites
… two decades, materials engineers have developed piezoelectric-polymer composite materials that enable effective electromechanical properties to be tailored for a specific application. These materials are made by combining conventional piezoelectric ceramics with piezoelectrically passive polymers …
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Investigating Ferroelastic and Piezoelectric Vibration Damping Behavior in Nickel-Barium Titanate and Nickel-PZT Composites
Ferroelectric and piezoelectric ceramic reinforced metal matrix composites are new materials being explored for vibration damping purposes. The high damping ability of ferroelectric and piezoelectric ceramics such as barium titanate (BaTiO3) and lead zirconate titanate (PZT) is due to the anelastic …
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Multi Array, Conformable Ultrasound Patch for Soft Tissue Imaging
… transducer is dictated by the properties of the piezoelectric material being used. One current drawback to ultrasound is that it is heavily operator dependent. This has motivated research into developing ultrasound systems that are conformable to the body and capable of obtaining relevant …
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Low-Power System Design for Impedance-Based Structural Health Monitoring
… results. Impedance-based SHM utilizes a piezoelectric ceramic as a collocated actuator and sensor, which measures the electrical impedance of the piezoelectric ceramic over a certain frequency range. The impedance profile of a structure under monitoring is compared against a reference …
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Feasibility study in using intelligent-materials to create actuators with muscle capabilities that can enhance prosthetics
… shape memory alloys, electro active polymers, piezoelectric ceramics and carbon nanotubes. A product design specification that described the material's fulfillment of specified design requirements was used to select one of the materials for further development. Actuators that can obtain similar …
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Design and characterization of acoustic pulse shape memory alloy actuators
… and material energy density comparable to piezoelectric ceramics make Ni- Mn-Ga an interesting active material. However, their usefulness is limited by the bulky electromagnet required to produce a magnetic field. In this thesis, a novel actuation method is developed for shape memory alloys …
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An experimental investigation into active damage control systems using positive position feedback for AVC
… used strain gages as the sensing element and piezoelectric ceramics as the actuator. Initial investigations into sampled-data systems using PPF are presented. The issues addressed are: stability of the sampled system, the effects of the sampling rate on the system, and degradation from …
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Modeling and Synthesis of a Piezoelectric Ceramic-Reinforced Metal Matrix Composite
… capability in the form of Joule heat for any piezoelectric ceramic-reinforced metal matrix composite system. Specifically, barium titanate (BaTiO₃), lead titanate (PbTiO₃), and zinc oxide (ZnO) piezoelectric ceramics have been modeled as dispersed particles shaped as spheres, prolate …
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Variational Modeling of Ionic Polymer-Based Structures
… electromechanical coupling similar to that of piezoelectric bimorphs. Ionomeric polymers are much more compliant than piezoelectric ceramics or polymers and have been shown to produce actuation strain on the order of 2\% at operating voltages between 1 V and 3 V \citep{Akle2}. Their high …
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Induced Damping And Its Relationship To Beneficial Energy Harvesting In Dielectric Elastomers With Application To Walking
… of electromechanical smart materials such as piezoelectric ceramics, which are often brittle, have low elastic modulus and can exhibit large strains without substantial stress generations. One type of EAP, the dielectric elastomer (DE), which utilizes electrostatic forces built up across the …
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Design and Analysis of Piezoelectric Transformer Converters
Piezoelectric ceramics are characterized as smart materials and have been widely used in the area of actuators and sensors. The principle operation of a piezoelectric transformer (PT) is a combined function of actuators and sensors so that energy can be transformed from electrical form to …
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Magnetoelectric Oxide Nanocomposite Heterostructures
… for candidates thin film materials with a high piezoelectric coefficient, which is a critical factor for ME composite films, I utilized the simple compositional BaSn0.11Ti0.89O3 bulk ceramic material as a target to grow films with the large piezoelectric properties. The grown high qualify …
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Development of MRI-compatible Transducer Array for Focused Ultrasound Surgery: : The Use of Relaxor-based Piezocrystals
… FUS, from the point of view of the potential piezoelectric material of choice. Two materials are of particular interests in this work: Binary (x)Pb(Mg1/3Nb2/3) O3 - (1-x)PbTiO3 (PMN-PT) piezocrystal, and newly specialized FUS material, PZ54 ceramic. A characterization methodology was developed …
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Techniques for Controlling Structural Vibrations
… the quadratic absorber. Using a DC motor, piezoelectric ceramics, and Terfenol-D struts as actuators and potentiometers, strain gages, and accelerometers as sensors, we demonstrate successful single- and multi-mode vibration control. In order to realize a more versatile implementation of …
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Nonlinear Control of Plate Vibrations
… shaker. Strain gages are used as sensors, while piezoelectric ceramic patches are used as actuators. The control technique is implemented using a dSPACE digital signal processing board and a modeling software (SIMULINK). Both numerical and experimental results show that the control strategy is …
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Synthesis-Structure-Property Relationships in Lead-Free Piezoelectric Materials
Piezoelectric materials find applications in multitude of devices such as sensors, actuators and energy harvesters. However, most of these piezoelectric materials utilize lead-based systems which are becoming serious problem owing to the restrictions imposed by regulatory agencies across the globe. …