Dynamic viscoelastic measurements of suspension for the drying process in tape casting

• Published in: Nihon Seramikkusu Kyōkai gakujutsu ronbunshi Vol. 100; no. 1167; pp. 1352 - 1356
• Main Author: Nagata, Koichi
• Format: Journal Article
• Language: Japanese
• Published: 01.01.1992
• ISSN: 0914-5400
• DOI: 10.2109/jcersj.100.1352

Dynamic viscoelastic properties of aqueous alumina suspensions containing acrylic resin were studied in the drying process in tape casting. Suspensions with pH 7.5 and pH 10.4 were used. The solid content of suspensions was changed by vacuum drying or adding water. In a suspension with pH 7.5 the storage modulus, tan delta , and viscosity increased drastically at the solid content of 80.5 wt%. Below the critical solid content, the yield stress of suspension was nearly zero, and the suspension showed Newtonian flow behavior. On the other hand, in a suspension with pH 10.4, the storage modulus and viscosity increased gradually at the smaller critical solid content of 76.0 wt%. Below the critical solid content, the suspension had a high yield stress and showed shear-thinning flow behavior. Green sheets from a suspension with pH 10.4 showed a low packing density. It was also found that the storage modulus of suspension above the critical solid content was a linear function of the strength of the resultant green sheet.