Low voltage piezocomposite actuators based on PZT tubes and plates

Abstract
Adaptive solutions based on piezoceramic actuators and sensors for noise reduction, vibration and shape control, micro positioning as well as health monitoring and health control gain in importance not only in automotive but also in mechanical engineering, machining and equipment industries. Commercially available multilayer actuators show high stiffness, high blocking force and short response time. But they are very fragile against non-axial loads, which is one reason of the limited use in mechanical engineering. Recently, the Fraunhofer IKTS developed a new generation of piezoceramic transducers, the so-called custom shape piezocomposites, which are based on PZT tubes and plates. The new actuators work in the d₃₁-mode (contraction) and are especially failure tolerant against non-axial loads. They can easily be formed according to custom needs, which makes them suitable for integration in various structural components. Because the electric field is applied across the wall thickness of the PZT tubes or plates, the piezocomposite actuators can be driven at low operating voltages.