Effects of the Amount of Dispersant and Binder on Slurry and Sheet Properties in Aqueous Tape Casting of Barium Titanate
Yuuta ISAKA, Haruhisa SHIOMI and Koji INAOKA
Abstract: In this study,tape casting of barium titanate was performed by using water-based slurry. The effects of the amount of dispersant and binder on the behavior of Ba2+ leaching and sheet properties such as linear shrinkage and warpage for sintered sheets were investigated. The amount of Ba2+ leaching was measured by inductively coupled plasmaiICPj emission spectrometry and fluorescent X-ray analysis. After firing at 1250 and 1300 for 2h, a linear shrinkage and warpage were measured. It was shown that addition of dispersant leads to an increase in Ba2+ leaching due to a decrease of pH of slurry. Linear shrinkage and warpage of the fired sheets increased at high binder content. The change in the warpage with dispersant was remarkable at high binder content. The warpage can be attributed to the particle packing of the sheet. SEM photographs showed that there is a difference in particle packing between upper and bottom sides of the sheets at high binder content. This leads to differential shrinkage during firing, resulting in greater warpage. Key Words:Aqueous tape casting, Ba2+ leaching, Linear shrinkage, Warpage, Dispersant, Binder