Effects of circumferential stress on tangentially polarized piezoelectric cylinders.

This paper investigates the dependence of the electromechanical properties of the tangential polarized (stripe-electroded) cylindrical piezoelements made of the hard (PZT-4 like) and soft (PZT-5A like) ceramics on the compressive circumferential stress produced by hydrostatic pressure. Results are presented for the relative change of the effective dielectric constants, elastic constants, coupling coefficients, and piezoelectric moduli. The sensitivity of dielectric constant and piezoelectric modulus to the compressive stress is shown to be less than radially polarized ceramic.

Increasing piezoelectric effect in radially polarized soft piezoelectric cylinders by pressure treating and its practical applications.

Subjecting soft piezoelectric ceramics such as lead zirconate titanate (PZT)-5 to uniaxial stress in a direction perpendicular to the principal polarization axis is known to increase its transverse piezoelectric modulus [Krueger, J. Acoust. Soc.

Piezoelectric cylindrical discs and solid rods: Dependence of the resonance frequencies and effective coupling coefficients on aspect ratio.

Dependencies of the resonance frequencies and effective coupling coefficients for solid circular cylindrical piezoelements (discs) of finite size are considered as a function of their height-to-diameter aspect ratios, h/2a. At aspect ratios in the range of approximately 0.5 < h/2a < 1.

Nonuniform piezoelectric circular plate flexural transducers with underwater applications.

An analytical treatment is presented for circular flexural plate transducers that have nonuniform electromechanically active-passive mechanical systems with particular interest in underwater applications. The analysis is made using the energy method that was previously applied to calculating parameters of uniform fully active (bimorph) circular plate transducers [B. S.

Piezoelectric circular ring flexural transducers.

An analytical treatment of the piezoelectric ceramic complete ring transducer undergoing flexural vibrations is presented. Conditions for the electromechanical excitation of the flexural vibrations are discussed and it is shown that the fundamental mode of the flexural vibration of a complete ring can be considered as sufficiently dominant over a broad frequency range. Hence, the one-dimensional equivalent electromechanical circuit representation of the transducer is applicable and all the parameters of the equivalent circuit are determined.

Piezoelectric slotted ring transducer.

Analytical treatment of a slotted piezoelectric ceramic ring transducer vibrating in flexure is presented. The mode shape of the slotted ring vibration is determined, and parameters of the equivalent electromechanical circuit of the transducer are calculated. Possibilities to optimize the effective electromechanical coupling coefficient of the transducer by combining active and passive materials are considered.

On the dynamic measurement of constants of piezoelectric single-crystal materials.

An error in the estimation of piezoelectric material properties can arise when applying the common measurement procedures in the IEEE Standard to determining constants of piezoelectric materials with exceptionally high coupling coefficients, in particular, single-crystal materials. The probable sources of inaccuracy in the resonance-antiresonance method, when applied to bar samples made of single crystals are considered. An additional method of dynamic measurements that helps to avoid the shortcomings of the resonance- antiresonance method is proposed, and its application is illustrated with examples of measurement of single-crystal piezoelements of different compositions.

Analytical modeling of piezoelectric ceramic transducers based on coupled vibration analysis with application to rectangular thickness poled plates.

The energy method for analyzing piezoelectric ceramic transducers [B. S. Aronov, J.