Abstract :
The dielectric properties of Ba(Zr0.25Ti0.75)O3+xY 2O3 ceramics are investigated. We believe that, integrating with the lattice parameters, there is an alternation of substitution preference of yttrium ions for the host cations in perovskite lattice that is responsible for the Curie point. The T c rises with the increase of Y 3+ doping when the doping content is less than 0.05 at%, owing to the replacement of Y 3+ ions for Ba2+ ions at the A-site; when the Y 3+ content is more than 0.05 at%, Y 3+ ions tend to occupy the B-site in perovskite lattice, causing a drop of T c . Owing to the modifications of Y 3+ doping, the loss tangent of BZT ceramics is depressed remarkably, making it a superior candidate to replace widely used lead-contained ceramics.
