Enhanced piezoelectric performance of ceramic-polymer composite cantilevers with thin metal substrates
In this work the electromechanical properties of lead zirconate titanate-poly(vinylidenefluoride-trifluoroethylene) ceramic-polymer composite on thin brass and steel substrates were investigated. Samples were stencil printed on metal foils and cured at 120 °C. The effective transverse piezoelectric coefficient (d31eff) was calculated by utilizing the converse piezoelectric effect and measuring the displacement of a cantilever sample’s tip in an electric field. Interestingly the results showed improved piezoelectric properties with the stiffer steel substrate samples. The highest d31eff achieved was about -22 pm/V which was 29 % higher than in samples printed on brass foil (-17 pm/V). Both are substantially higher compared to the coefficients reported with similar ceramic-polymer composites on polymer substrates. The improvement is suggested to originate from the prevention of buckling effects and more effective bending deformation while the structure remained flexible. Due to the high effective values of d₃₁ and g₃₁ the developed material and cantilever structures are feasible for both sensor and energy harvesting applications.