Mechanical flexibility, faster processing, lower fabrication cost and biocompatibility enable poly(vinylidene fluoride) (PVdF) to have a wide range of applications. This work investigated the use of a piezoelectric polymeric material, PVdF, in combination with 3D printing, to explore new strategies for the fabrication of smart materials with embedded functions, such as sensing or actuation. The motivation behind this research was to design and fabricate PVdF thin films that will be used as pressure sensors and will have applications in active intelligent structures. In this work, 3D printed PVdF thin films with thickness values in the range of 250 to 350 μm were poled under high electrical fields which was varied from 0 to 10 MV/m. Copper electrodes were applied, forming a standard capacitor layered structure, to facilitate poling and to collect piezoelectric output voltage. The poling process enabled the piezoelectric crystalline phase transition of printed PVdF films to transfer from the α-phase to the piezoelectric active β-phase and rearranged the dipole alignment of the β-phase. The efficiency of poling was evaluated through the measurement of the charge generated by poled PVdF films in response to mechanical effort. The experimental results demonstrated higher voltage outputs under stress. Samples were tested at stepped poling high voltages, and results from pressure testing demonstrated higher electrical output with increased poling voltages. The results also indicated the ratio of phase transitions increases with the increased electric field. It is believed that this demonstrates a path towards fully functional 3D printed smart materials with embedded functions, such as sensing, for instance piezoelectric sensing, and actuation.


The Effects of Additive Manufacturing and Electric Poling Techniques on PVDF Thin Films: Towards 3D Printed Functional Materials

Division / Sponsors: 
Aerospace Division

Paper Proceedings: https://asmedigitalcollection.asme.org/SMASIS/SMASIS2020/volume/84027

SMASIS2020 - Virtual Conference

Supporting the need among researchers worldwide for additional online and multimedia content, ASME now offers the ASME Conference Video Collection. This platform will collect and provide long-term access to conference presentation videos, encompassing all technology areas within ASME's technical conference and events program. About 30,000-40,000 engineers across all mechanical engineering and related disciplines participate in ASME conferences each year. This includes authors of approximately 6,000 to 8,000 technical papers published by ASME, the majority of whom also submit video presentations for our virtual conferences. The video collection will be available as an add-on to existing product packages or as a separate subscription.