Anhysteretic strains in ferroelectric ceramics under electromechanical loading

Abstract

This study investigates anhysteretic strains in PZT ceramics. The anhysteretic curves are associated with a stable balanced state of polarisation in the domain structure, excluding dissipative effects associated with mechanisms such as domain wall pinning. Anhysteretic measurements are representative of a -ideal- scenario in which the material would undergo no energy loss due to dissipative processes, focusing on the stable and reversible aspects of the domain configuration. The different methodologies employed to measure deformations under electromechanical loading are presented, leading to the introduction of digital image correlation (DIC) as the chosen technique, recognised for its ability to capture detailed information on transverse and longitudinal strain. The article then describes a comprehensive procedure developed to obtain anhysteretic curves. The subsequent presentation of the results of the transverse and longitudinal strain analyses provides valuable insights into the reversible and irreversible behaviour of the material. They can be used as a basis for the thermodynamical modelling approaches grounded on the separation of reversible and irreversible contributions.