Integration of PZT Thick Films on Additively Manufactured Substrates for Vibrational Energy Harvesting Applications

Abstract

The presented research is aimed at the integration of screen-printed thick films (50-100μm) of PbZrTiO3 (PZT) on additively manufactured stainless steel substrates for vibration energy harvesting. The manufacturing technologies advanced by this research opens new horizons for energy harvesting applications as it standardizes the development and manufacturing processes, thereby making vibration energy harvesters more feasible. Since the parts are built layer-by-layer, the thickness of the different layers of the substrate can be controlled. The substrates under study were manufactured using Powder Bed Infusion additive manufacturing technology from Stainless Steel 17-4 PH powder. Simple cantilever harvesters are chosen as an initial target to focus on the optimization of the screen-printing process. The sample is 15.6 mm long, 4.1 mm wide and 0.35 mm thick cantilever beam with a 50μm thick PZT screen-printed layer sandwiched between two gold electrodes. A dielectric layer printed on the stainless steel substrate was introduced to promote adhesion. With 6.1mm of the beam length clamped and no tip mass the experimental resonant frequency was 2kHz. The maximum output power was 39 nW under a resonant base acceleration with an amplitude of 0.3g at a load resistance of 100 kΩ. A good fit was found with a Finite Element Model with a difference of 5%. These initial results open routes for optimized designs of printed piezoelectric energy harvesters.