Multilayer piezoelectric actuator with AgPd internal electrode

Using 70Ag/30Pd paste as an internal electrode which can be sintered at low temperature and have cost down effect in mass productions, multilayer piezoelectric actuators (MPAs) were fabricated with 75 layers, 30 μm thickness layer, by conventional multilayer capacitor(MLC) techniques. The multilayer piezoelectric actuators had no defects such as diffusions of the internal electrode to ceramic body and shortage of internal electrodes. The MPA did not show the cracks in the ceramics parts and the gapping phenomena in the external electrodes when Ag paste was used as external electrodes. The MPA devices showed a maximum displacement of 4 μm at 100 V dc voltage and kept the maximum displacement constant for 300 s. The MPA showed good matching properties between ceramic bodies and AgPd internal electrodes. We confirmed the possibility of large scale production of the multilayer piezoelectric actuators with superior electrical properties and a cost down effect using 70Ag/30Pd paste as an internal electrode.