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Effect of interparticle forces, bimodal particle size distribution, and slurry viscosity on particle packing in alumina bodies consolidated by pressure filtration is presented. The requirements for packing colloidal particles to their highest density are strong repulsive interparticle forces and optimum particle size distribution. Even though these conditions are met, the high packing density in consolidated bodies may be adversely affected by particle segregation resulting from sedimentation. Therefore, the slurry during consolidation must have a sufficiently high viscosity to prevent sedimentation. [

Dispersed ceramic slurries with high concentrations of indifferent electrolyte have been shown to effectively eliminate mass segregation effects in composite materials. Furthermore, high packing efficiencies have been achieved with these systems. It has been suggested that the addition of high concentrations of indifferent electrolytes to an otherwise dispersed ceramic slurry modifies the interaction potential so that the short-range adhesive attraction is diminished by additional repulsive forces. This lower attractive force is still high enough to cause coagulation which raises the viscosity, but small enough to allow easy particle rearrangement during filtration or centrifugation. This rearrangement leads to high packing densities. The effectiveness of this behavior on the improvement of ceramic powder processing of composites is demonstrated with Al2O3 and ZrOz.[