A semi-analytical scale bridging approach towards polycrystalline ferroelectrics with mutual nonlinear caloric-electromechanical couplings

https://doi.org/10.1016/j.ijsolstr.2020.05.016Get rights and content
Under an Elsevier user license
open archive

Abstract

Various caloric aspects of polycrystalline ferroelecrics are investigated, based on an efficient modelling approach. In this context, both linear reversible effects, leading to heating or cooling of the material, and nonlinear dissipation heating, being associated with ferroelectric domain switching, are considered. The semi-analytical approach focusses on the constitutive behavior of a polycrystalline representative volume element (RVE) under the impact of combined electromechanical loadings, incorporating mutual interactions of caloric and electromechanical fields within a framework of non-equilibrium thermodynamics. Temperature dependence of material coefficients is further taken into account. The so-called condensed method (CM) is employed to bridge the scales of domain wall motion within grains and grain interaction in the RVE. Results are compared to those of finite element simulations and experiments taken from literature, illustrating hysteresis loops and dissipation heating due to cyclic electrical loading. Additional findings illuminate the role of mechanical compression during electric cycling, behaviors of single vs. polycrystals, and separate the impacts of linear and nonlinear caloric effects.

Keywords

Dissipation heating
Pyroelectric effect
Piezoelectrics
Domain switching
Condensed method

Cited by (0)