Microstructural, piezoelectric properties and temperature stability in Li0.02(Na0.55K0.45)0.98[(Nb0.77Ta0.18Sb0.05)1 − 2x/5Cux]O3 ceramics for piezoelectric actuator

In this study, Li0.02(Na0.55K0.45)0.98[(Nb0.77Ta0.18Sb0.05)1 − 2x/5Cux]O3 (LNKNTS-x Cu) piezoelectric ceramics with x = 0–0.015 were fabricated by conventional solid-state reaction method. The temperature stability of kp was investigated. At the sintering temperature of 1120 °C and 0.6 mol% Cu content, the optimum values of density = 4.808 g/cm3, kp = 0.446, Qm = 109, εr = 1359 and d33 = 254 pC/N, were obtained, respectively. Taking into consideration above physical properties, it is considered that this composition is applicable to lead-free haptic piezoelectric actuators with good temperature stability in the temperature range of − 20 to 80 °C.

► (Na,K)(Nb,Ta,Sb)O3 system ceramics substituted with Cu were fabricated.
► The temperature stability of 0.6 mol% Cu specimen was suitable for piezoelectric actuator.
► The optimum values of kp = 0.446 and d33 = 254 pC/N were obtained, respectively, at 0.6 mol% Cu content.