Fast 3D Digital Light Process Printing of PVDF‐HFP Composite with Electric In Situ Poling System for Piezoelectric Applications
Hoseong Song, Hai Li, Sooman Lim
Abstract
Abstract 3D printing systems are being used more and more due to the combination of energy materials, such as combinations of polyvinylidene fluoride‐co‐hexafluoropropylene (PVDF‐HFP) composites, that has become possible recently. However, to obtain strong piezoelectric properties, the poling step where a high voltage is applied to a part for a long period of time is indispensable due to the nature of the material. This inconvenience is the largest obstacle to widespread acceptance of this technology so, from an industrial perspective, tackling this issue is vital. In this paper, the authors build an in situ poling system suitable for PVDF‐HFP composites into a digital light processing (DLP) printing system that is able to greatly shorten poling times while improving the piezoelectric properties of the resulting materials. This approach achieves a ten times reduction in the total process time needed to produce piezoelectric films with a piezoelectric coefficient of 42 pC N −1 when compared to the typical time needed to complete a post‐poling process that gives similar piezoelectric properties. In addition, a piezoelectric device printed using the authors' approach reveals its great potential for producing large‐area flexible sensors with high sensitivity ( R 2 = 0.99) and excellent mechanical durability (10 000 cycles).