Low-temperature sintered K0.5Na0.5NbO3-based ceramics for vibratory gyro-sensor applications

Abstract

0.91K0.47Na0.47Li0.06NbO3-0.09NaSbO3 lead-free piezoelectric ceramics were prepared at 1000°C using a sintering aid comprising of Cu and Ba in a molar ratio of 71.5/28.5. A dense structure with a high density of 4.43 g/cm3 was obtained for the ceramic added with 2.5 wt% of the sintering aid. Probably due to the smaller grains and doping of Cu2+, the piezoelectric coefficient and dielectric loss were reduced to 120 pC/N and 1.0%, respectively. The ceramics were then fabricated into vibratory gyro sensors of dimensions 0.6 mm × 0.6 mm × 4 mm; and good sensitivity (~0.7 mV/dps) was obtained in the range of -360 to 360 dps.