Piezoelectric and ferroelectric properties of (Bi,Na)TiO3-(Bi,Li)TiO3-(Bi,K)TiO3 ceramics for accelerometer application

The piezoelectric and ferroelectric properties of 0.76(Bi0.5Na0.5)TiO3-0.04(Bi0.5Li0.5)TiO3-0.2(Bi0.5K0.5)TiO3 (abbreviated as 0.76BNT-0.04BLT-0.2BKT) ceramics were investigated to clarify the optimal sintering temperature, and the vibration characteristics were examined for a compression-mode accelerometer assembly in which 0.76BNT-0.04BLT-0.2BKT ceramics sintered at the optimized temperature served as the piezoelectric elements. The increase in the grain size of the 0.76BNT-0.04BLT-0.2BKT ceramics with the sintering temperature provides a beneficial contribution to the piezoelectric coefficient; however, it detrimentally contributes to the depolarization temperature. The charge sensitivity of the prototype accelerometers was evaluated with changes in the seismic mass and the layer number of the piezoceramics. The deviation between the theoretical and measured values of charge sensitivity was less than 10%.