Orientation and Temperature Dependence of Piezoelectric Properties for Sillenite-Type Bi12TiO20 and Bi12SiO20 Single Crystals

Abstract

Abstract:The full matrix of electro-elastic constants of sillenite-type crystals Bi 12 TiO 20 (BTO) and Bi 12 SiO 20 (BSO) were determined by the resonance method, with d 14 and k 14 being on the order of 40-48 pC/N and 31%-36%, respectively. In addition, double-rotated orientation dependence of d 33 was investigated, with the maximum values of 25-28 pC/N being achieved in ZXtl45°/54°-cut samples. The electrical resistivity of BSO was found to be two orders higher than that of BTO, being on the order of 7 × 10 5 Ω cm at 500 °C. The temperature dependence of dielectric and piezoelectric properties were investigated. BSO exhibited a high thermal stability in the temperature range of 25-500 °C, while BTO showed a variation of ~3% in the range of 25-350 °C. The high values of d 14 and k 14 , together with the good thermal stability, make BTO and BSO crystals potential candidates for electromechanical applications in medium temperature range.

Elastic properties of single crystal Bi12SiO20 as a function of pressure and temperature and acoustic attenuation effects in Bi12MO20 (M = Si, Ge and Ti)

“…The results by Yu and Min (2004) (Brillouin interferometry) as well as Schweppe and Quadflieg (1974) are comparable with our results (table 2). The single-crystal elastic stiffness coefficients c 11 and c 12 by Shen et al (2014) deviate considerably from the results of this paper (table 2).…”

“…The evaluation was carried out by a non-linear least-squares procedure in which the observed resonance frequencies were compared to those calculated from sample dimensions, experimental density, dielectric permittivity and a trial set of elastic coefficients and piezoelectric stress coefficient. Initial values of c ij were taken from literature (Schweppe and Quadflieg 1974, Gospodinov et al 1988, Yu and Min 2004, Shen et al 2014. The calculated resonance frequencies were obtained by solving a general eigenvalue problem, the rank of which was equivalent to the number of basis functions used for the development of the components of the displacement vector.…”

“…ò 0 denotes the permittivity of vacuum. The change of the relative dielectric permittivity at constant stress within the temperature range between 300 K and 700 K was neglected due to a minor variation in s   11 0 of about ±1% (Shen et al 2014).…”

“…Full sets of elastic stiffness coefficients have been reported for BSO in the temperature range of 250 K-300 K (Gospodinov et al 1988(Gospodinov et al , 1992 and at pressures up to 0.16 GPa (Gospodinov et al 1988). Shen et al (2014) investigated full sets of electromechanical parameters of BSO and BTO between 300 K and 773 K. The stability of BSO up to 770 K was confirmed by Raman-spectroscopic measurements (Salke and Rao 2012).…”

“…Sillenites exhibit large piezoelectric effects, i.e. d 123 of BSO is about 20 pC N −1 , which is about 8 times larger than d 111 of α-Quartz, and they are potential piezoelectric materials for electromechanical applications (Shen et al 2014).…”