An alternative method for the measurement of the clamped capacitance of disk shaped piezoelectric ceramics

Abstract

Several measurement methods for the dielectric permittivity at constant strain ε₃₃ ^S of a piezoelectric ceramic have been proposed¹⁻². In this paper a comparison of these methods is made and an alternative and complementary method is proposed. This method requires a clear and well shaped thickness resonance and is based on the measurement of the electrical input impedance at the frequencies f_s and f_p of the fundamental resonance of the thickness extensional mode of vibration. Other parameters - k_t and Q_m - can also be obtained from these measurements¹⁻³.

Several samples of different piezoelectric ceramics have been measured and the results using the proposed and the above mentioned methods are compared.