Co-firing of LNT/Ag Multilayer Sheets Prepared by Aqueous Tape Casting

Multilayer ceramic sheets composed of Li1.075Nb0.625Ti0.45O3 (LNT) layers and silver metal layers were fabricated by aqueous tape-casting method. LNT green tape was prepared using PVA (polyvinyl alcohol) as binder and ethylene glycol as plasticizer. The influence of the slurry composition on the theological properties of the slurries and the properties of the resultant green tapes were studied. The slurry exhibited a typical shear thinning behavior. The increase in the PVA content increased the tensile strength of the tapes. The slip compositions with 5 wt pct PVA produced green tapes with satisfactory tensile strength. Ethylene glycol additions enhanced the flexibility of the green tapes but also produced a decrease in the tensile strength. Sliver inner-electrode was pasted on LNT green tapes and the sheets were stacked, pressed and sintered at 900℃ for 2 h. SEM (scanning electron microscopy) micrographs showed that the multilayer sheets were fully dense with fairly uniform microstructure and no reaction was observed between LNT and sliver layers.