Porous Multilayer PZT Materials Made by Aqueous Tape Casting
Porous piezoelectric ceramics are of interest for hydrophones and medical imaging because of their enhanced coupling with water or biological tissue due to acoustic impedance matching. Multilayer lead zirconate titanate (PZT) substrates with dense and porous interlayers were produced by tape casting of aqueous PZT slips with high solids contents. The use of latex binders with low viscosity enabled addition of starch as a fugitive additive to create air/ceramic composites with ´3-3´connectivity. Microstructures, piezoelectric and mechanical properties of sintered, poled laminates were evaluated. The relative permittivity, ε33, decreased by 40% for laminates with porous interlayers compared to dense ones, whereas the relative decrease in piezoelectric longitudinal coefficient, d33, was 35%. Laminates with porous interlayers maintained 72% of their bending strength compared to dense ones.
Marc Anglada et al.
L. Palmqvist et al., "Porous Multilayer PZT Materials Made by Aqueous Tape Casting", Key Engineering Materials, Vol. 333, pp. 215-218, 2007