New slurry characterization technique for optimizing wet-shaping process (part 2) - Dependency of centrifugal effect on slurry consolidation process

In order to design optimal particulate slurries to be applied in wet-shaping process, concentrated alumina slurries have been subjected to a centrifugal consolidation method, in which the mechanical properties of slurry are measured methodically by controlling the centrifugal effect. The slurry with high solid content is readily forced to form a particle network structure at the percolation threshold, the formation mechanism of which originates in a slight dehydration of slurry, The critical initial solid content for the network structure has been found to be as low as several vol%, It is demonstrated that it exists a relation between the centrifugal consolidation stress and the packing fraction, and that this relation can be interpreted to characterize the mechanical strength of the formed network structure, on which the solids content and the degree of flocculation exert a significant influence, Compared with the network structures formed from well-dispersed slurries, those from weakly-flocculated slurries have lower mechanical strength, accordingly leading to higher final equilibrium packing fraction of green bodies.