Domain switching in polycrystalline ferroelectric ceramics.
Ferroelectric ceramics are widely used as sensors and actuators for their electro-mechanical properties, and in electronic applications for their dielectric properties. Domain switching--the phenomenon wherein the ferroelectric material changes from one spontaneously polarized state to another under electrical or mechanical loads--is an important attribute of these materials. However, this is a complex collective process in commercially used polycrystalline ceramics that are agglomerations of a very large number of variously oriented grains. As the domains in one grain attempt to switch, they are constrained by the differently oriented neighbouring grains. Here we use a combined theoretical and experimental approach to establish a relation between crystallographic symmetry and the ability of a ferroelectric polycrystalline ceramic to switch. In particular, we show that equiaxed polycrystals of materials that are either tetragonal or rhombohedral cannot switch; yet polycrystals of materials where these two symmetries co-exist can in fact switch.
Li
J Y
JY
Department of Engineering Mechanics, University of Nebraska, Lincoln, Nebraska 68588-0526, USA.
Rogan
R C
RC
Ustündag
E
E
Bhattacharya
K
K
D002516:Ceramics / Q000737:chemistry*; D019245:Compressive Strength; D003198:Computer Simulation; D003460:Crystallization / Q000379:methods*; D004548:Elasticity; D004563:Electrochemistry / Q000379:methods*; D007501:Iron / Q000737:chemistry*; D008422:Materials Testing; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D013314:Stress, Mechanical
D007501:Iron