Effect of Dispersants on the Rheological Properties and Slip Casting of Concentrated Alumina Slurry

Abstract

Slip casting is one of the most common forming techniques used in the fabrication of ceramics. To obtain successful casting results, one need first to fully deagglomerate the ceramic powders and get concentrated slurries with good rheological properties. In this work, the rheological properties of concentrated alumina slurries were studied as functions of solid contents and quantities of two different dispersants, i.e., sodium pyrophosphate and diammonium hydrogen citrate. It was found that these properties could be satisfactorily related to the maximum packing fractions which were determined from sedimentation experiments. Our results also indicated that an optimum deflocculation process can always lead to optimal casting and sintering results. Copyright © 1989, Wiley Blackwell. All rights reserved