Influence Of Multple Factors On The Self-recovery And Re-degradation Phenomena Of Lead Zirconate Titanate Piezoelectric Ceramics

PZT(Lead Zirconate Titanate) as a kind of piezoelectric ceramics, because of its outstanding piezoelectric properties and low costs, it has been widely used in electronic mechanical devices, such as: piezoelectric motors, actuators etc. However, there is a phenomenon of electrical degradation will occur during the applications of piezoelectric materials under d.c. electrical field, which greatly influences the performance and serve life of the piezoelectric materials. The electrical degradation will causes the resistance and performance decrease of piezo ceramic and finally leads to failure of the piezo ceramic. The rate of degradation will significantly increase while enhancing the electric field intensity across the piezoelectric elements or inceasing the condition temperature and humidity. Therefore, the useful life of product will be shortened greatly under harsh operating environment.A kind of piezoelectric ceramics samples with good electrical performance and higher rate of degradation has been prepared in this project and the microstructure of the samples has been characterized. It concluded: the time of the piezoelectric ceramic self-recovery is longer, the re-degradation time is longer, and the time of re-degradation is of 0.4477 times of the self-recovery time; It is nothing to do with the self-recovery and the degree of degradation; The self-recovery volt is higher the time of re-degradation is shorter; There is a critical field( Ec) on the piezoelectric ceramic, just below this field, self-recovery and re-degradation will occur. There works provide a theoretical basis for further improving the service life-time and the reliability of piezoelectric ceramics in industrial applications.