Abstract
A dynamic durability test system was constructed and checked which can change the preload, temperature and driving voltage for piezoelectric pellets of lead zirconate titanate (PZT) ceramics. Durability tests on samples with various initial properties revealed that decrease in electromechanical coupling factor was less for samples which have lagre coercive fields. In addition, the same tendency was observed for the samples which have higher Curie temperatures, indicating that the improvement of coercive field and Curie temperature prevents property degradation.