High Temperature Electrostrictive Ceramics

TRS Technologies proposes to develop high temperature electrostrictors from bismuth-based ferroelectrics. These materials will exhibit high strain and low loss in the 400 to 500?C temperature range, enabling the development of robotic components such as high power ultrasonic transducers and high force actuators for NASA?s planned missions to Venus. Such devices are currently made from piezoelectric Pb(Zr,Ti)O3 ceramic (PZT), which does not operate above 350?C. Existing high temperature piezoelectrics (such lead titanate and quartz) are only useful for sensor applications. They do not have high enough properties or low enough electromechanical loss for actuators and transducers. Electrostrictive materials have been successively used for high precision positioning actuators and high power sonar projectors. They have inherently low losses regardless of operating temperature. The materials developed on Phase I will be specifically designed to operate at 460?C, the Venus surface temperature. Other types of actuators such as pneumatic, hydraulic, electro-active polymer, and shape memory alloy will be difficult if not impossible to implement at such high temperature. In the Phase I program TRS will fabricate 460?C electrostrictors and demonstrate their feasibility for transducers and actuators with strain vs. field measurements. Actuators and ultrasonic devices will be developed in Phase II.