Internal friction related to the mobility of domain walls in sol-gel derived PZT ceramics

Internal friction Q–1 and Young‘s modulus E were measured as functions of temperature for undoped Pb(Zr0.65Ti0.35)O3 ceramics obtained by the sol-gel technique. Experiments were performed with a RAK-3 resonant mechanical spectrometer. The E(T) curves show two anomalies associated with two peaks, PR and PF, in the Q–1(T) dependence. Moreover, Q–1(T) curves recorded for two different frequencies show that the PR peak has a relaxation character. It was found that its activation energy and relaxation time should be attributed to the interaction of domains with point defects. Key words: sol-gel method; ferroelectric ceramics; PZT; internal friction; domain structure 1