Ferroelectric relaxor Ba(Ti,Ce)O₃

Abstract

The dielectric behaviour of Ba(Ti1−yCey)O3 solid solutions (y = 0–0.3) has been studied. A small amount of Ce doping (y = 0.02) has weak influence on the dielectric behaviour of Ba(Ti1−yCey)O3. With increasing Ce concentration, three phase transitions of pure BaTiO3 are pinched into one rounded dielectric peak with frequency dispersion, and the relaxation time follows the Vogel–Fulcher relation. The evolution from a normal ferroelectric to a ferroelectric relaxor is emphasized. High strains (S = ∼ 0.1–0.19%) with a small hysteresis under ac fields are obtained in ferroelectric relaxors Ba(Ti1−yCey)O3. The physical mechanism of the relaxation process, the pinching effect of the phase transitions and their influence on the ferroelectric and electrostrictive behaviour are discussed.