Phase-field modeling for ferroelectrics in a multi-scale approach [Elektronische Ressource] / von Benjamin Völker

Phase-field modeling for ferroelectricsin a multi-scale approachZur Erlangung des akademischen GradesDoktorderIngenieurwissenschaftender Fakultät für Maschinenbau desKarlsruher Instituts für Technologie (KIT)genehmigteDissertationvonDipl.-Ing. Benjamin Völkergeboren am 20.05.1982in Bad KissingenTag der mündlichen Prüfung: 21.12.2010Hauptreferent: Prof. Dr. M. KamlahKorreferent: Prof. Dr. O. KraftK Prof. Dr. C. ElsässerAbstractToday’s development and improvement of ferroelectric materials is mainly based on experimen-tal approaches. In order to significantly reduce development time and costs in the future, thereis a demand for a virtual material development. The primary objective of this thesis is applyingphase-field modeling in a knowledge based multi-scale simulation approach for the ferroelec-tric polycrystalline ceramics lead titanate (PTO) and lead zirconate titanate (PZT). Within thisapproach, phase-field modeling bridges the gap between predictive atomistic methods on oneside and micromechanical modeling methods on the other side. Therefore, two interfaces in thismulti-scale simulation chain have been developed and established in this work.In order to link the atomic level to the meso-scale, results from first-principles calculations andatomistic shell-model simulations are employed as input parameters for the phase-field model.