Piezoelectric properties of Sr2Bi4Ti5O18-Ca2Bi4Ti5O18 solid solution ceramics

Piezoelectric properties of Sr2Bi4Ti5O18 (SBT)-Ca-2 Bi-4 Ti5O18 (CBT) solid solution, that is, Sr2(1- x) Ca2xBi4Ti5O18 [SCBT- x ] (0 <= x <= 1) with m = 5, were investigated. Effects of grain orientation in SCBT system on their piezoelectric properties are also studied using the hot-forging (HF) method. On the ordinarily fired (OF) samples without orientation, electromechanical coupling factor, k(33), and piezoelectric constant, d(33), of the MnCO3 (0.4 wt%) doped SCBT-0 were 0.15 and 26 pC/N, respectively. On the other hand, the HF-SCBT-0 showed relatively high k(33) and d(33) values of 0.29 and 51 pC/N, respectively. Temperature coefficient of the resonance frequency, TC-f r , in the (33) mode of SCBT-0 (OF) and HF- SCBT-0 were -89.2 ppm/degrees C and -63.0 ppm/degrees C, respectively.