Journal of the American Ceramic Society, Vol.102, No.10, 6147-6155, 2019
(Na1/2Bi1/2)TiO3-based lead-free co-fired multilayer actuators with large strain and high fatigue resistance
Large-strain multilayer actuators (MLAs) were fabricated by tape-casting 0.91(Na-1/2 Bi-1/2)TiO3-0.06BaTiO(3)-0.03AgNbO(3 )(NBT-BT-3AN) lead-free incipient piezoceramics co-fired with Pt inner electrodes. Microstructures, dielectric properties, unipolar and bipolar strain, as well as fatigue properties of the MLAs were investigated. It was found that the actuator consisting of 15 ceramic layers with individual thicknesses of 114 mu m could output a large unipolar strain of 0.3% and a dynamic displacement of 5 mu m at 6 kV/mm at room temperature. It exhibited excellent cycling stability and provided a high strain of 0.23% after 10(7) cycles at 6 kV/mm. Moreover, these MLAs still can deliver a strain of 0.20% at 125 degrees C.
Keywords:cycling stability;large strain;lead-free piezoceramics;multilayer actuators;temperature stability