Methodology to evaluate variations in piezoelectric constants after aging process

ABSTRACT

Piezoelectric ceramic properties change with time. Detected aging effects for PZT ceramics are; the difference in the value of the dielectric constants diminishes, whereas dielectric losses and elastic stiffness increases. In this work, an optimisation technique based on adjusting a finite element model to reproduce the complex impedance curves of a resonant piezoceramic disk is analysed aiming to detect changes due to aging. This technique allows estimating all material parameters, both their real and imaginary parts. The optimisation uses the constitutive equations of the piezoelectric effect in the linear regime. The evolution of elastic, piezoelectric and dielectric constants is evaluated after 5 years of aging. To compute the ten complex parameters, the piezoelectric model is adjusted to minimise the difference between finite element simulations and the experimental data. Results presented here, show that the proposed technique is sensitive enough to detect changes in the individual parameters due to aging process.

KEYWORDS:

• Ceramics
• aging
• piezoelectric parameters
• electromechanical resonances
• complex impedance
• FEM optimisation

Acknowledgements

The authors thank ‘JECS Trust grant for attendance to the Winter School on Advanced Characterization of Piezoceramics, Cercedilla, Madrid (Spain). 19–22 February 2017’.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Mariana del Castillo http://orcid.org/0000-0001-7729-3209

Additional information

Funding

The authors thank the Consejo Superior de Investigaciones Científicas, CSIC (grant n. COOPB20160; Fundación General CSIC), the Fundação de Amparo à Pesquisa do Estado de São Paulo, FAPESP (grant n. 2012/20731-7) and the Uruguayan funding agencies CSIC and Agencia Nacional de Investigación e Innovación, ANII.