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Piezoelectric 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.

This work focuses on the development of piezoelectric sensors for the fractional flow reserve (FFR) technique, a procedure based on the measurement of blood pressure within a vessel to evaluate the severity of coronary stenosis. Considering the medical application, biocompatibility is a mandatory requirement that justifies the selection of fillers and matrix. Two composites made of lead‐free barium titanate nanoparticles (BaTiO3) incorporated in polydimethylsiloxane (PDMS) elastomer are developed: the first composite with particles randomly dispersed and the second one with particles aligned along one direction, via an innovative technique known as dielectrophoresis. The experimental characterization indicates that the electroactive and dielectric properties are coherent with the models’ prediction, confirming that the alignment of the filler gives rise to considerably enhanced dielectric and piezoelectric proprieties relative to the random dispersion. Thermal stability together with X‐ray diffraction is conducted, demonstrating superior piezoelectric response of the structured sample under high‐temperature conditions. FFR application is then simulated by applying an arterial pulse‐shape stimulus on the developed sensor, which is finally integrated into a catheter and directly inserted in a simulation arm.