Latest Developments of Multilayer Piezo Actuators with Copper Internal Electrodes

M. Galler, F. Rinner, M. Ottlinger, A. Glazunov, P. Windisch, A. Pecina, H. Kastl
EPCOS OHG, Deutschlandsberg, Austria

Abstract:
TDK presents its newest generation of EPCOS multilayer piezo actuators for high power applications. This includes a new ceramic material with highest coupling factor, pure copper internal electrodes, a device design with maximum active stack volume, and an innovative material for mounting the outer contacts. Compared to conventional piezo actuators, the new EPCOS piezo actuators feature a significantly higher active volume ratio and, as a result, 20% more efficiency in terms of elongation and force. Furthermore, they have no polarization cracks, and the outer electrical contacts are robust even under long time high temperature exposure. The new
EPCOS piezo actuators feature the same performance with a volume that is 20% lower. In addition, they can achieve a strongly increased number of cycles even at extreme elongation and temperatures up to 190 degC, and they exhibit excellent resistance against humidity.