Choosing the best geometries for the linear characterization of lossy piezoceramics: Study of the thickness-poled shear plate

Abstract

Resonance modes of a thickness-poled piezoceramic shear plate are studied. When determining material properties from impedance measurements, it is required to obtain an uncoupled shear resonance. The shear resonance, which is electrically excited, results to a series of plate resonances, which is mechanically excited by this, when frequencies match. Thus, the condition of a high aspect ratio of the plate is not valid to eliminate coupling. Instead, the thickness ͑t͒ and lateral dimensions ͑L , w͒ of the plate must be tailored for each material. This approach was tested for a commercial piezoceramic and plates amenable for characterization obtained for aspect ratios below L : t =15:1 ͑L = w͒.

Ferroelectric, Dielectric and Electromechanical Performance of Ba0.92Ca0.08Ti0.95Zr0.05O3 Ceramics with an Enhanced Curie Temperature

“…It is mandatory for the calculation of piezoelectric, elastic, and dielectric coefficients from monomodal resonance. This means that the main resonance for analysis should not be coupled with other natural resonances of the vibrator [ 28 ]. The radial resonance is the lowest possible resonance of the think disk, and it is naturally unaffected by overtones of lower frequency resonances.…”

“…An automatic iterative method was used for the analysis of the radial and thickness modes of thin ceramic disks [ 26 , 27 ]. Furthermore, parameters obtained from the shear resonance mode of a rectangular plate (thickness poled) [ 28 , 29 ] were calculated using the same method. For this purpose, alternative plots to the conventional representation of the complex impedance as modulus and phase angle were used.…”

“…Piezoelectric losses are less commonly reported and there is no convention about them. From well-known relations with the directly calculated parameters at resonance [ 26 , 27 , 28 , 29 ], the other parameters and also the electromechanical coupling factors (k x , with x = planar(p), thickness(t), 31 and 15) were determined: …”

A systematic analysis of the radial resonance frequency spectra of the PZT-based (Zr/Ti = 52/48) piezoceramic thin disks

“…After knowing the difference between f s and f p , the values of k p and k eff can be calculated to be 60% and 53% from Eqs. (13) and (14), respectively. In fact, the most complicated relationship is between the effective coupling factor k eff and the planar coupling factor k p due to both transcendental equations for the resonance and antiresonance.…”

“…The introduction of new piezoelectric ceramics with improved electrical properties usually requires alternatives to the method of determining the material constants associated with radial mode resonance. In the past few decades, numerous authors developed many efficient methods for characterizing the material constants of piezoceramics in the radial model [10][11][12][13][14]. Moreover, some non-analytical methods are also used for identification of the elastic, dielectric, and piezoelectric constants of piezoceramic disk resonators [15,16].…”