Barium titanate tape casting

It is also possible to retain the hydrothermally produced barium titanate particles in aqueous suspension to form the basis of a tape-casting slurry capable of producing < 3 /mi dielectric layers. This route avoids the risk of the formation of hard agglomerates on drying the precipitates. 

Ferroelectric ceramics (such as barium titanate, lead zircanate titanate) Sensors and actuators, electronic memory, optical applications Tape casting, sputtering, pressing, templated grain growth Improved dielectric and piezoelectric properties... 

Ceramic particles in organic liquid media behave differently from those in aqueous media. Many known ceramic-processing techniques involve fine particles dispersed in nonaqueous media. Some of the better known examples are tape casting of barium titanate and aluminum nitride powders and tape or slip casting, extrusion, and injection molding of ceramic high Tc superconductor powders. 

The slurry formulation for tape casting barium titanate sheets consists of the following ingredients barium titanate powder, phosphate ester, methyl ethyl ketone, ethanol, acrylic resin, benzyl butyl phthalate, and poly(ethylene glycol), (a) Explain the function that each of the ingredients has in the formulation, (b) What would be the usual amounts (in wt%) of each of the ingredients in a typical tape cast formulation ... 

In addition to the multilayered ceramic capacitors just described, many of the barium titanate-based compounds that exhibit high dielectric constants are used in single-layer tape-cast capacitor devices. Relaxor materials such as lead magnesium niobate (PMN), which are characterized by high dielectric constants, broad dielectric maxima, and low sintering temperatures, have been manufactured in thin sheets by tape casting. 

K. R. Mikeska and W R. Cannon, Dispersants for Tape Casting Pure Barium Titanate pp. 164-83 in Advances in Ceramics, Vol. 9, Forming of Ceramics. Edited by J. A. Mangels and G. L. Messing. The American Ceramic Society, Westerville, OH, 1984. 

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