Grain-scale strain heterogeneity as a function of crystallographic texture in phase-change electro-mechanical ceramics

Abstract

A reduction in the orientation distribution of grains, via crystallographic texturing, is known to significantly enhance the electro-mechanical response in polycrystalline piezoelectrics. Through calculations of the electric-field-induced strain in phase-changing ceramics, the local strain heterogeneity was also found to increase with crystallographic texture. The increase in grain-scale strain heterogeneity potentially indicates greater stress concentrations within the polycrystal and may degrade the expected lifetime and fatigue behavior in these ceramics. In crystallographic symmetries with higher numbers of polarization directions, it was found that the magnitude of heterogeneity in the response was lower.

Control of polarization in bulk ferroelectrics by mechanical dislocation imprint

“…In mechanically deformed samples, dislocations are concentrated in some parts of the sample and depinned domain walls can therefore move for longer distances. In bulk ceramics, templated grain growth (28,29) affords outstanding properties, as demonstrated for energy storage materials with supreme reliability (30).…”