Finite Element Modelling of Impedance Spectroscopy Data in Composite Electroceramics

TL;DR

This paper presents a finite element modeling approach for impedance spectroscopy in composite electroceramics, accounting for complex 3D granular structures and grain boundary effects, revealing the influence of grain shape on impedance data.

Contribution

It introduces a novel finite element modeling method that accurately simulates impedance spectra considering realistic grain and boundary geometries in electroceramics.

Findings

Grain shape significantly affects impedance spectra.

High bulk to grain boundary ratios are achievable with mixed element types.

Simulation results align with experimental observations.

Abstract

A time domain finite element numerical study of impedance spectroscopy in composite electroceramics is presented. The simulations take into account the complexity of the realistic three dimensional granular structure including grains and grain boundaries. Two types of finite elements are used to represent the bulk (tetrahedrons) and the grain boundary (prisms) phases, which allow using extremely high bulk to grain boundary ratios. Simulations at various frequencies reveal a strong influence of the grain shape on the impedance data of the sample, both at low and at high frequencies.