Piezoelectric actuators with Cu inner electrode

The piezoelectric material composition is PZT-SKN with a Li2CO3 flux. This system has been developed successfully for air-fired actuators in PSU with Ag-Pd alloyed inner electrodes. We tried to control the lead activity by adding higher excess PbO in the formulation. Samples were all sintered at 900°C for 6 hours in PO2 = 5.38×10¿12 atm. With 3.0, 4.0wt% PbO excess addition, we note that density, micro-structure and permittivity are similar and there is a high electro-mechanical performance for example, the high field piezoelectric d33 was ~480pm/V. However, there is some decrease in d33 after the sintering in low PO2 and Rayleigh coefficients shows PO2 to slightly suppressing both the intrinsic and extrinsic contribution to piezoelectric properties. Multilayer actuators with copper inner electrode were successfully fabricated with the PZT-SKN after processing with techniques and materials that have low residual carbon.