Stress and strain determination during piezoelectric resonance using digital image correlation

Accurate experimental determination of deformation, stress, and strain values, as well as their distributions across the sample during high-frequency vibration, is of utmost importance for resonance piezoelectric applications. Here, we present a novel approach using Digital Image Correlation (DIC) to measure the displacement and determine strain and stress distributions in piezoceramic materials under resonance conditions. Conventional methods for piezoelectric resonance characterization rely on electrical or point-based displacement measurements, which fail to provide comprehensive full-field data and frequently require contact of the sensor for displacement or strain measurement. In this study, a stroboscopic DIC setup enabled non-contact, full-field displacement mapping at frequencies reaching up to 265 kHz with a sensitivity better than 50 nm. The findings demonstrate heterogeneous strain and stress profiles for transverse (31) and longitudinal (33) vibration modes of Pb(Zr,Ti)O₃ ceramics, consistent with analytical predictions and finite element modeling. This approach establishes DIC as an effective tool for the experimental characterization of piezoelectric materials, allowing visualization and quantification of strain and stress during resonance operation.