Inhomogeneous electric field-induced structural changes in soft lead zirconate titanate ferroelectric ceramics. (March 2022)

• Record Type: Journal Article
• Authors: Zhao, Jianwei; Funni, Stephen D.; Molina, Emily R.; Dickey, Elizabeth C.; Jones, Jacob L.
• Is Part Of: Acta materialia. Volume 226(2022)
• Publication Date: 2022-03
• Subjects: Lead zirconate titanate -- X-ray diffraction -- Ferroelectric -- Domain switching -- Phase transition; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Mechanical properties -- Periodicals; Metallurgy -- Periodicals; Chemistry, Inorganic -- Periodicals; 620.112
• DOI: 10.1016/j.actamat.2022.117682
• Languages: English
• ISSNs: 1359-6454

Abstract

Abstract: Under the application of an external voltage, high electric field concentrations can develop around the interdigitated electrode edges inside multilayer ceramic actuators (MLCAs). The spatial distribution of the local electrical field can create local inhomogeneity in the electromechanical response. To investigate the complex field inhomogeneity in MLCAs, partially electroded Nb-doped PbZrx Ti1-x O3 samples were investigated via synchrotron-based high-energy X-ray diffraction (XRD) as a function of applied electric field. These in situ experiments allowed us to probe the structural changes as a function of position relative to the electrode edge and calculate the local degree of domain alignment, from which the local electric field directions were inferred. The domain switching behavior, both in amplitude and orientation, was found to be spatially dependent across the inactive regions in partially electroded samples. Specifically, the degree of domain alignment and field-induced phase transitions are amplified near the electrode edge. The orientation-dependent phase transitions are also amplified for the tetragonal composition near the morphotropic phase boundary (MPB), i.e., the Nb-doped PbZr0.53 Ti0.47 O3 composition. Finite element analysis (FEA) shows spatially-dependent, inhomogeneous electric field distributions in the partial-electrode samples, which closely match the experimentally inferred local electric field directions from XRD. The correlation of FEA and experimental data from XRD corroborates that the ferroelectric domain orientation distributions are being directed, primarily, in the direction of the electric field. Graphical abstract: Image, graphical abstract