High-performance (K,Na)NbO ₃-based multilayer piezoelectric ceramic actuators with nickel inner electrodes

Multilayer piezoelectric ceramic actuator (MLCA) has been widely employed in actuators due to the large cumulative displacement under low driving voltage. In this work, MLCA devices consisting of a lead-free MnCO3 and CuO doped 0.96(K0.48Na0.52)(Nb0.96Ta0.04)O3–0.04CaZrO3 (KNN) base Ni metal inner electrode were well co-fired by two-step sintering process reducing atmosphere. The layer/electrode interface is well-integrated clearly continuous without distinct interdiffusion chemical reaction, which beneficial electrical reliability MLCA. As result, laminated with nine active layers obtains an ultrahigh coefficient d33 3157 pC/N, about times than bulk ceramics. 0.5 mm–thick composed series ~50 μm–thick ~3 electrodes reaches high 1.8 μm applied voltage 200 V (the same requires as 3700 for ~1 ceramic). excellent performance low-cost reveal that KNN-based MLCAs are promising candidate application.