An aqueous tape casting of Li1.075Nb0.625Ti0.45O3 (LNT) ceramics was developed using PCA-NH4 as dispersant, PVA as binder and EG as plasticizer. Flexible, defect-free and smooth tapes of LNT were successfully produced. The study focused on obtaining the optimum slurry formulations and on the effects of the processing parameters such as the stability, the rheology on the properties on the tape characteristics. Surface properties of LNT powders in the aqueous suspensions are distinctly influenced by PCA-NH4. The zeta potential measurement showed that the isoelectric point (IEP) of LNT powders in the absence of dispersant corresponds to a pH value of 3.7. The zeta potential values (absolute values) increased with the amount of dispersant and up to its maximum near pH 9-10. The rheology measurements of all the slurries investigated showed the desired shear thinning behavior, indicating that the LNT slurry was homogenous and well stabilized. An optimum formulation for the tape was investigated and it was shown that a high solid loading (50 wt%) would lead to a high relative green density (46.7%). Homogenous, smooth, and defect-free green tapes were successfully obtained by an appropriate slurry formula.

Keywords: Aqueous tape casting, Li1.075Nb0.625Ti0.45O3, Zeta potential, Rheology.