Download or read book Systematic Characterization of PZT 5A Fibers with Parallel and Interdigitated Electrodes written by Nicholas Wyckoff and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Lead zirconate titanate (PZT) fibers are mainly used in active fiber composites (AFC) where they are embedded in a polymer matrix. The PZT fibers provide the electromechanical actuation and sensing capabilities derived from the inherent piezoelectricity of PZT. The role of the epoxy matrix is to transfer the external loads amongst the fibers while also serving as protection to enable more flexibility in the AFC device as a whole. Interdigitated electrodes (IDE) placed on the planar surfaces of the AFC are along the direction of the fibers, hereby exploiting the d33 coefficient of PZT, which is twice that of the d31 coefficient. Despite this clever strategy, the AFC electromechanical response is lower than that of bulk PZT. Although the polymer matrix has been widely studied, the PZT fibers have not. By directly characterizing the behavior of PZT fibers, recommendations to redesign of the AFC with the goal of improving its performance can be proposed. Therefore, it is important to characterize the electrical and electromechanical behavior of these fibers ex-situ using the IDE configuration to assess the impact of fiber configuration and non-uniform electric field on the piezoelectric response. For this reason, the broad goal of this thesis is to characterize 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. As mentioned above, limited research has been conducted on characterizing the behavior of PZT fibers, and no electrical characterization of individual PZT fibers has been done to the best of our knowledge. Therefore, to accomplish the broad goal of this study, the following research tasks are planned: 1.) To characterize PZT fibers with parallel electrodes; the parallel electrode testing will determine baseline properties that will be compared to the IDE results and will also allow for quantification of the fiber geometry's impact on the bulk PZT properties. 2.) To characterize PZT fibers using IDE configuration; the characterization of PZT fibers ex-situ with the IDE configuration will convey the PZT fiber behavior in the AFC to assist in improving the AFC design. 3.) To experimentally determine Young's modulus, coercive field, remnant polarization, dielectric permittivity and both d33 and e33 piezoelectric coefficients of PZT fibers. To the best of our knowledge, these results will be the first dielectric permittivity, d33 and e33 values determined with direct measurement of PZT fibers using both parallel electrode and IDE configurations. These results will allow for direct comparison of bulk PZT and PZT fiber properties as well as the impact of the nonuniform electric filed generated by the IDE. The PZT fiber mechanical properties and dielectric permittivity measured with parallel electrodes were found to be approximately 65% of the bulk PZT fibers. The fiber's Young's modulus was determined to be 33 GPa and the dielectric permittivity determined to be 1115. The PZT fiber IDE remnant polarization, dielectric permittivity, and e33 results were found to be within the range of 50%-75% of the results found for parallel electrode configuration. The combined reduction found in the PZT fiber properties compared to bulk PZT leads to the conclusion that implementing the fiber properties into AFC models will result in a substantially different response.