LAUSR

ABSTRACT The material properties and damage characteristics of lead zirconate titanate(PZT) ceramics were investigated at various temperatures. A positive voltage was obtained when the sample was cooled from 20°C to −190°C, while a negative voltage was obtained when the sample was heated from −190°C to 180°C. The difference between the positive and negative values depended on the thermal stress. Compressive stress generated a more positive voltage in the cooling process, while tensile stress led to a more negative voltage in the heating process. The voltage values also depended on the cooling (or heating) rate of the sample, e.g. the greater the cooling (or heating) rate, the greater the voltage. When cyclic loading was conducted mechanically at −190°C, the voltage reduced, but it was recovered after heating to 20°C. Damage of the PZT ceramic (90° domain switching) was detected when the sample was cooled to −190°C due to the high thermal stress.