Strain and Current Responses During Electron Flux Excitation of Piezoelectric Ceramics

Abstract

The electric field induced strain in piezoelectric materials subjected to an electron flux is examined in this paper. An analysis using quantum mechanics indicates that stable and controllable strains with very low current draw should be achievable over a range of positive and negative control potentials. The model also predicts instability in the internal electric field at larger negative potentials.The model was evaluated by observing the strain output of PZT5h plates subjected to an electron flux on one face and voltage inputs from a single electrode on the opposite face. The strain response and current flow were measured as a function of electrode potential and electron energy. All of the significant predictions of the model were verified by the experimental results. Further experiments were performed to examine the time response of the strain induced in the plate. It was found that the location and potential of the electron collector dramatically influences the dynamic response of the system.

Hierarchical Morphing Control of an Ultra-Lightweight Electro-Actuated Polymer Telescope with Thin-Film Actuators

“…The initial stages of this research were undertaken at the University of Kentucky, involving extensive experimental investigations into the strain response of piezoelectric materials under electron flux. These investigations encompassed both polymers [26] and ceramics [27,28]. The method capitalizes on secondary electron emission by regulating the electron flux intensity on one side of the film while simultaneously controlling the potential difference, in conjunction with a back pressure voltage, on the opposite side.…”

“…It is noteworthy that, in this scenario, the metal coating for electrode purposes is applied solely to the side with the back pressure voltage. From a theoretical modeling perspective, many approaches have been conducted qualitatively, relying on techniques, such as the diagrammatic approach [27] and theoretical deductions utilizing principles from quantum mechanics [28].…”

“…In this case, controlling the potential difference becomes straightforward, as it involves independently tuning U B . This approach is similar to the application described in [27,28]. The computation of the generated quasi-static strain follows Equation (2), with an electric field input of E = (U B − U P )/t F at the excited node within this one-dimensional model.…”