Charged Interfaces, Linear and Point Defects in Ionic Ceramics—Equilibrium and Kinetic Effects

The properties of ionic solids enable the development of a wide variety of applications that range from sensors and actuators to structural materials, and from energy capture and conversion to storage technologies. For all these applications, a wide variety of processing routes exist to consolidate an initial granular powder that will be later used as a starting point for the fabrication of carefully thought out layers and multifunctional architectures. Sintering of ceramics, in particular, is a processing methodology that is a result of the underlying contributions from individual point (vacancies and interstitials) line defects (dislocations), and surfaces and interfaces, as they interact in a local microstructural, mechanical, chemical, and electrical field induced through local or external stimuli. In this presentation, by starting from fundamental thermodynamic concepts, a phase field theory is presented to describe the chemical and electric field-induced mechanisms that control their microstructural evolution and resultant transport and structural properties. The impact of these mechanisms at the particle and grain level are assessed and compared against experimental observations