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

Abstract

Multilayer piezoelectric ceramic actuator (MLCA) has been widely employed in actuators due to the large cumulative displacement under the low driving voltage. In this work, the MLCA devices consisting of a leadfree MnCO3 and CuO doped 0.96(K0.48Na0.52)(Nb0.96Ta0.04)O3-0.04CaZrO3 (KNN) piezoelectric ceramic and a base Ni metal inner electrode were well co-fired by the two-step sintering process in a reducing atmosphere. The ceramic layer/electrode interface is well-integrated and clearly continuous without distinct interdiffusion and chemical reaction, which is beneficial to the electrical reliability of the MLCA. As a result, the MLCA laminated with nine active ceramic layers obtains an ultrahigh piezoelectric coefficient d33 of 3157 pC/N, about nine times than bulk ceramics. The 0.5 mm-thick MLCA composed of a series of ~50 μm-thick ceramic layers and ~3 μm-thick Ni electrodes reaches a high 1.8 μm displacement under the low applied voltage of 200 V (the same displacement requires J u s t A c c e p t e dJournal of Advanced Ceramics https://mc03.manuscriptcentral.com/jacer 2 voltage as high as 3700 V for ~1 mm-thick bulk ceramic). The excellent electrical performance and low-cost base electrode reveal that the KNN-based MLCAs are promising lead-free candidate for actuator application.

Enhanced piezoelectric performance of Cr/Ta non-equivalent co-doped Bi 4Ti 3O 12-based high-temperature piezoceramics

“…Because of their excellent piezoelectric properties, lead zirconate titanate (Pb(Zr,Ti)O 3 , PZT) ceramics have been widely used [1]. However, the Curie temperature (T C ) of the PZT ceramics is below 380 ℃ [2], which cannot meet the needs of hightemperature piezoelectric applications. Moreover, due to the toxicity of lead elements to both health and the environment, researchers have been pursuing lead-free alternatives [3,4].…”