The rheological characteristics of a zirconium dioxide based suspension were investigated, and an optimization of the composition for implementation of the gel casting technology (gel-casting) was proposed. Commercial zirconia powder, partially stabilized with 3 mol % yttria and doped with 0.25 wt % alumina, was used in the experiments. Acrylamide and N,N-methylenebisacrylamide monomers were used to obtain the polyacrylamide gel. Compositions with varying contents of the dispersant Dolapix CE 64 and zirconia powder were prepared. By electroacoustic spectroscopy, the average particle size of the prepared ceramic suspension was determined to be 0.056 μm (56 nm). It was established that at this particle size the system is sufficiently stable for casting. The influence of pH, dispersant content, and ZrO2 powder concentration on the suspension’s zeta potential and viscosity was studied. Optimum ranges of pH and Dolapix CE 64 content were determined. During the experiments, the ZrO2 powder loading was increased to 38 vol % while maintaining satisfactory casting properties of the suspension: low viscosity, resistance to flocculation, and low particle sedimentation rate.
Shokodko et al. (Wed,) studied this question.