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Solid axially polarized piezoelectric ceramic cylinders are often used and available in many sizes from several manufacturers. The electrodes are applied on the flat surfaces. They are known as disks and rods when the ratio of the diameter to the length is much greater than one and much lesser than one, respectively. The ANSI/IEEE Standard methods can be used to determine some of the elastic, dielectric, and piezoelectric coefficients of cylinders with ratio much greater or much lesser than one. In the Standard method, the input electrical admittance is measured and the coefficients are determined by equating the analytical values of a few functions such as the low frequency capacitance and the frequency at which the input electrical admittance is maximum to the corresponding measured values and solving the resulting equations. The method works well when the ratio satisfies the assumptions used to derive the analytical model. Cylinders with a ratio that is neither much greater nor much lesser than one are often used in devices. A method to determine their coefficients is of interest for two reasons. One, the cylinder is only a part of the device and it is necessary to accurately know its coefficients to build a model of the cylinder and the device. Two, the coefficients of several cylinders are not the same even when they are all made using the same procedure and it is of interest to know the spread in their values as this affects the spread in the characteristics of the device. In this paper, an analytical model of a solid axially polarized piezoelectric ceramic cylinder with arbitrary dimensions and boundary conditions [D. D. Ebenezer et al. J. Acoust. Soc. America 117 (6), 3645-3656 (2005)] is used to develop a method to determine its coefficients. Experiments are most easily done using cylinders with stress-free boundary conditions as other boundary conditions are difficult to achieve; and it is easier to measure the input electrical admittance than other functions such as displacement or stress. Therefore, the method is based on the use of the input electrical admittance of a stress-free cylinder. Ten coefficients are necessary to completely describe piezoelectric ceramics but only nine occur in the linearized axisymmetric governing equations. The tenth coefficient occurs in the expression for normal radial stress. The coefficients are determined by iteratively refining them until the computed values of certain functions are in good agreement with the measured values. The accuracy of the method is determined by using functions computed using a finite-element model in place of measured values.
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