Temperature dependent characteristics of Cerambow actuators

A new type of piezoelectric actuator has been developed called the Cerambow. Cerambow technology is based on a thermal contraction mismatch between two bonded layers which results in a stress-biased structure. For this investigation, brass substrates were solder-bonded to PLZT 1/53/47 and 5.5/56/44 disks at an elevated temperature. During cooling, stresses are imparted to the ceramic by the metal and a domed structure results. The displacements of Cerambows were recorded as a function of temperature under both loaded and non-loaded conditions. The results showed a fairly constant displacement up to approximately 100/spl deg/C, followed by a rapid decrease to the maximum temperature of 160/spl deg/C. After thermal cycling, the displacements were found to be close to the initial displacement values. Prior to and after thermal cycling, the mechanical quality factor and the effective coupling coefficient of the dome mode for each sample were calculated.