ACOUSTIC-EMISSION AND DOMAIN SWITCHING IN TETRAGONAL LEAD-ZIRCONATE-TITANATE CERAMICS

The electric field-induced acoustic emission (AE) in a poled tetragonal lead zirconate titanate (PZT) ceramic was measured at room temperature and related to the polarization switching, held-induced strain, dielectric constant, and piezoelectric constant in the high-voltage electric field. The AE signals became most remarkable when the polarization approached the saturation, while they became minimal when the polarization reversal occurred. The AE count, expressed as a function of electric field, exhibited a hysteresis loop similar to the strain loop. These data suggest that the AE signals were generated by the strain due to 90 degrees domain switching rather than the piezoelectric strain.