Effect of substrate to piezoceramic layer thickness ratio on the performance of a C-shape piezoelectric actuator

This paper is focused on the influence of the thickness ratio between substrate and piezoceramic layers on the displacement and force output of a C-shape actuator. The ratio of substrate/PZT layers thickness is one of the parameters that can be used for the optimization of performance of a C-shape actuator. Experimental and Finite Element software (MSC Marc) was used for validation of the theoretical results. The results show that with a fixed piezoceramic layer thickness, the thickness, hence the stiffness of the substrate layer can be varied to obtain a range of values of displacement and force. With increasing thickness of substrate, the free displacement reaches a maximum value after which it decreases. The possible causes for this behaviour are discussed. This information is a useful guide to designers enabling the selection of appropriate material and geometry for a C-shape actuator, depending on whether the primary requirement is large force or large displacement. The information is also useful when deciding on the required number of individual C-shape actuators in series or parallel.