PZT-based suspensions for tape casting

A PZT powder of composition Pb-0.988(Zr0.52Ti0.48)(0.976) Nb0.024O3 was prepared by conventional mechanical mixing of the raw materials in water, freeze-drying and calcination. Sedimentation tests of four deflocculants in an azeotropic mixture of methyl ethyl ketone/ethanol were carried out to check the dispersing effect. Attention was focused on a phosphate ester based deflocculant. Electrical conductivity and electrophoretic mobility were investigated. Slurries for tape casting were prepared with commercial binder and plasticizer and different volumes of solid. The rheological behaviour was recorded as yield stress values and flow curves. The slurries were tape-cast and technological results compared with previous characterization results. (C) 1996 Elsevier Science Limited.