Effects of solids loading and dispersion schedule on the state of aqueous alumina/zirconia dispersions

Journal Article · Sat Oct 01 04:00:00 EDT 1994 · Journal of the American Ceramic Society; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1994.tb04663.x· OSTI ID:6862361

Wernet, J; Feke, D L ^[1]

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1. Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Chemical Engineering

The effects of solids loading and dispersion order on the state of aqueous slips of either zirconia or alumina, and binary slips of these two powders, have been examined. Since these powders can acquire surface charge when they are dispersed in aqueous media, changes in the ionic composition of the slip can occur as a result of the addition of solids. At higher solids loading, a substantial fraction of the ionic activity within the slip may be attributed to the solid itself. As the solids loading within unary powder suspensions is increased, it is possible to drive the suspension pH toward the point of zero-charge for the powder, resulting in diminished electrostatic stabilization and possible powder agglomeration. An analytical model was constructed to account for the observed results. This embodies a simple surface site complexation model which was augmented to include material and charge balance constraints on ionized surface sites as well as solvated ions. For binary powder dispersions of lumina and zirconia, it was found that the order of dispersing the two components could have a pronounced effect on the overall suspension behavior. The variability in results is attributed to the solubility of the alumina in the basic processing media.

• OSTI ID: 6862361
• Journal Information: Journal of the American Ceramic Society; (United States), Journal Name: Journal of the American Ceramic Society; (United States) Vol. 77:10; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
AQUEOUS SOLUTIONS
CASTING
CHALCOGENIDES
DATA
DISPERSIONS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
EXPERIMENTAL DATA
FABRICATION
INFORMATION
IONIC CONDUCTIVITY
MATHEMATICAL MODELS
MIXTURES
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PH VALUE
PHYSICAL PROPERTIES
SLIP CASTING
SOLUTIONS
TRANSITION ELEMENT COMPOUNDS
ZIRCONIUM COMPOUNDS
ZIRCONIUM OXIDES