Silicon nitride-Nd2O3/Al2O3 powders prepared by precipitation of the oxide additives

Silicon nitride-Nd2O3/Al2O3 powder mixtures were prepared by in-situ precipitation of the sintering additives as hydroxides from an aqueous nitrate solution. It is shown that the surface charge characteristics of these powders are determined by the oxide additive layer. TEM studies verify the precipitation of nanosized oxide particles on Si3N4. The influence of organic additives on the surface charge properties of the suspended powder is discussed with respect to the preparation and the processing of aqueous slurries.