| abstract |
A method of forming substantially spherical ceramic beads that includes conveying an aqueous ceramic slurry to a nozzle tip that is immersed in an inert water-immiscible fluid layer. The nozzle tip is spaced a predetermined distance away from a rotating disk that is also immersed in the immiscible fluid layer. The rotating disk creates a shear force that at the nozzle tip that dislodges droplets of the aqueous ceramic slurry from the nozzle tip into the immiscible fluid layer. Once dislodged, the droplets assume a substantially spherical shape and a substantially mono-modal size distribution. The droplets are permitted to pass from the immiscible fluid layer into an aqueous gelling solution wherein the droplets are converted into rigid beads. In a preferred embodiment of the invention, the rigid beads are recovered from the gelling solution, washed, and then sintered to obtain a density of greater than about 98% of theoretical density and a sphericity of greater than about 0.95. The method can be used to fabricate substantially spherical zirconia-containing beads having a diameter within the range of from about 0.1 mm to about 2.0 mm that are useful, for example, as grinding media. |