Multilayer telescopic piezoactuator fabricated by a prototyping process based on milling

Abstract A miniature piezoceramic actuator with telescoping multilayer d33 tubes is presented. The monolithic structure was realized using a rapid prototyping process, which is evaluated and discussed. The process based on wet building, green machining and lamination has proven to be flexible, fast and suitable for small-scale prototyping of multilayer piezoceramic actuators. Green machining in a milling machine is not only used to shape the actual device, but also to pattern the internal electrodes in the multilayer structure. Patterning of internal electrodes using milling demonstrated as good pattern definition as an ordinary screen-printing process would give, but with a superior flexibility due to the lack of mask changes. A comparison of the fabricated actuator has been made with state of the art piezoelectric actuators utilizing magnifying mechanisms. The d33-actuated multilayer telescopic actuator has proved to be a promising component with a displacement amplification of about 5 and an energy density comparable to other levered actuator designs. Several routes to improve the performance of the first design are identified.