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Showing 1 to 20 of 85 for “"Piezoelectric Materials"”.
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High Performance Lead--free Piezoelectric Materials
Piezoelectric materials find applications in number of devices requiring inter-conversion of mechanical and electrical energy. These devices include different types of sensors, actuators and energy harvesting devices. A number of lead-based perovskite compositions (PZT, PMN-PT, PZN-PT etc.) have …
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An electromechanical system for characterization of piezoelectric materials
Piezoelectric materials have been used in medical applications for a long time due to their unique characteristics, which is to respond to mechanical stimulation by producing an electrical current and vice versa. They perform a pivotal role in medical applications both for diagnostic and …
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Structure determination of piezoelectric materials at extreme conditions
Diese Arbeit präsentiert Ergebnisse an piezoelektrischen Materialien aus der Langasitfamilie, die unter extremen Bedingungen untersucht wurden. Die Einkristalle aus dieser Familie, vor allem La3Nb0.5Ga5.5O14 (LNG) und La3Ta0.5Ga5.5O14 (LTG), sind vielversprechende Materialien für Oberflächenwellen …
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Simultaneous Energy Harvesting and Vibration Control via Piezoelectric Materials
… integrates a flexible solar cell array, flexible piezoelectric wafers, a thin film battery and an electronic module into a composite sandwich structure. The basic design factors are discussed for a beam-like multifunctional wing spar with load-bearing energy harvesting, strain sensing and …
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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. …
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Analytical Models to Predict Power Harvesting with Piezoelectric Materials
With piezoceramic materials, it is possible to harvest power from vibrating structures. It has been proven that micro- to milliwatts of power can be generated from vibrating systems. We develop definitive, analytical models to predict the power generated from a cantilever beam and cantilever plate. …
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Theory of piezoelectric materials and their applications in civil engineering
… mechanical energy into electrical energy using piezoelectric materials is studied. Applications of piezoelectric materials as actuators are also explored, with particular interest in the question: what is the maximum moment that an actuator, whose energy comes from piezoelectricity, can develop …
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The utilization of piezoelectric materials and optical fiber sensors for electric field detection
… sensor, and the actuation produced by a piezoelectric material when placed in an electric field. Classical electromagnetic theory is used to mathematically model the performance of the sensor within a given electric field. Experimental and theoretical results are presented which …
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Modeling a piezoelectric flag as a membrane for energy harvesting
The goal of this research is to model a piezoelectric flag as a membrane for the sake of energy harvesting. Typically, a flag is modeled as a beam, but it is modeled as a membrane in this study with the hopes of more accurately describing the dynamics of the system. Following this is an overview of …
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Active sensing in silicon-based MEMS resonators
… traditional mechanisms such as capacitive or piezoelectric sensing. This thesis explores FET-sensing in Si-based MEMS resonators with dielectric and piezoelectric materials for design of fully unreleased CMOS-integrated resonators for multi-GHz frequency applications. Monolithic integration of …
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Design, fabrication and characterisation of free-standing thick-film piezoelectric cantilevers for energy harvesting
… vibration to electrical energy is the use of piezoelectric materials, typically operating as a cantilever in a bending mode, which generate a voltage across the electrodes when they are stressed. Traditionally, the piezoelectric materials are deposited on a non-electro-active substrate and are …
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STRUCTURE AND PROPERTIES OF PIEZOELECTRIC NANOFIBERS FOR ELECTROMECHANICAL COUPLING APPLICATIONS
Many emerging applications demand flexible materials for efficient electromechanical conversions. With potential to improve flexibility and electromechanical coupling performance, due to the finite size effect and high specific surface areas, one-dimensional (1D) nanostructured piezoelectric …
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Tunable Piezoelectric Transducers via Custom 3D Printing: Conceptualization, Creation, and Customer Discovery of Acoustic Applications
… vice versa), so it can be interpreted as data. Piezoelectric materials are often used for transducer manufacturing, and recent advancements in additive manufacturing have enabled this material to take on complex geometric forms with micro-scale features. This work advances the additive …
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Performance Modeling and Efficiency Analysis for a Piezohydraulic Pump with Active Valves
Piezoelectric actuation is an expanding field that makes use of piezoelectric materials that have high power density as actuators. These actuation systems have the potential higher power density than the traditional servo motor technology. However, due to tiny strain of the piezoelectric materials, …
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Effects of temperature on the electrical impedance of piezoelectric elements
… Material Systems and Structures, employs piezoelectric (PZT) materials for tracking the structural impedance to qualitatively identify damage. The mechanical impedance of a structure is a function of the structure's mass, stiffness, damping, and structural boundary conditions. Changes in …
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Thermoplastic active fiber composites for structural actuation
The integration of piezoelectric actuators into a structure can lead to an active structural surface that can adapt by bending or straining to different operational conditions. This can be used to tune desired properties of the active system to their optimal levels. Due to their fast response time, …
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Material characterization and modeling for piezoelectric actuation and power generation under high electromechanical driving levels
High electromechanical loads parallel to piezoelectric polarization might result in depolarization of the material, depending on the material property itself and the external excitations such as electrical field, electrical driving frequency, stress and stress duration. In this work, material …
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Finite Element Simulation Of Repair Of Delaminated Composite Structures Using Piezoelectric Layers
… repair methods with the advancement in fields of materials, sensing and actuating. This can make the repair more effective and efficient than conventional repair methodology. Current research proposes the use of piezoelectric materials in repair of delaminated composite structures. A detailed …
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