Dielectric breakdown of PZT ferroelectric ceramics

The dielectric breakdown of the ferroelectric ceramics PZT 55/44 and PZT-8 were studied at room temperature. Two kinds of breakdown phenomena were observed. In one the sample cracks into several pieces after breakdown, and in the other one or more gaseous channels through the sample appear. The dielectric loss and conductivity of the samples as well as the relationship between the amplitude and duration of field imposed on the sample were measured. The dependence of these parameters on the breakdown mechanism was also studied.<>