Effects of impurity doping in lead zirconate-titanate ceramics

Abstract Impurity doping effects on the properties of lead zirconate-titanate ceramics have been investigated from the internal bias field viewpoint. The internal bias field is strengthened by doping with single or multiple acceptors, but is weakened by single or multiple donors. Equimolar mixed acceptor and donor dopants have no influence on the internal bias field. These facts suggest that the internal bias field is caused by complexes of acceptor atoms and oxygen vacancies. The internal bias field gives rise to effects on the domain wall motions. It prohibits the poling process, increases the mechanical quality factor and accelerates the aging change in the frequency constant. The mechanical quality factor and the aging change are proportional to the internal bias field. However, when the internal bias field reorients itself parallel to the spontaneous polarization in a short time after poling, the aging change becomes small, even for a specimen having a strong internal bias field.