Micro‐Structuration of Piezoelectric Composites Using Dielectrophoresis: Toward Application in Condition Monitoring of Bearings
Résumé
ezoelectric soft material based on inorganic/organic composites suitable for aerospace and aeronautical monitoring sensors is fabricated. The designed material is a piezoelectric composite made of lead zirconate titanate (PZT) filler embedded in a poly(dimethyl siloxane) (PDMS) matrix. To improve the piezoelectric properties of the film, the connectivity of the ceramic filler is increased via electric field‐assisted structuration, which leads to columnar arrangement of the filler across the thickness. This structure (1–3) shows higher piezoelectricity than one with randomly dispersed filler (0–3). Piezoelectric and dielectric activities of PZT/PDMS in 0–3 and 1–3 configurations at different volume fractions are compared. The results confirm that the 1–3 connectivity leads to superior piezoelectric behavior. Thermal stability of electroactive properties and high temperature X‐ray diffraction (XRD) analyses are performed: the composites maintain a good piezoelectric response, even at 200 °C. Following a process optimization, the piezoelectric behavior of this new class of composites approaches the fluorinated ferroelectric polymers one, with the advantages of piezoelectric properties stability preserved at a higher temperature and a lower poling electric field. In conclusion, there is potential for the integration of the designed sensor in aircraft ball bearings for condition monitoring.