Lead titanate based composition for multilayer actuators

Samarium and lanthanum modified lead titanate ceramic multilayer actuators, consisting of 20 active layer of thickness of 68/spl mu/ were processed by standard tape casting technology. Due to the low relative dielectric permittivity (210 at 1 kHz), high coercive field at room temperature (45 kV/cm) and high transition temperature (/spl sim/400/spl deg/C) of this ferroelectric material, the obtained multilayer structure presents low capacitance and a wide range of voltage and temperature for a quasi-linear strain response at low frequency. Although, due to the relatively low piezoelectric constants, the strain achievable is rather low, that characteristics made this material an alternative to the high capacitance and non-linear response at high voltage commercially available PZT piezoelectric actuator for special applications.