Forming processes of strontium barium niobate ceramics

Abstract

In forming strontium barium niobate (SBN) ceramics, two methods (pressure filtration and slip casting) were employed to investigate the consolidation behaviour. The zeta potentials were measured to understand the interparticle forces of SBN powders. It was found that the zeta potentials of SBN powders were negative above pH 2.2. Several experiments have been conducted to investigate the effect of pH on the rheological behaviour of SBN slurries with 20 vol% solids loading. The rheological behaviour of the slurries SBN with 20 vol% solids loading at pH 11.5 is shear thinning. It is suggested that the increase of the flow rate of the fluid might have the advantages to enhance the packing density and prevent fine particles from clogging in pressure filtration and slip casting. Two different moulds i.e. plaster and alumina have been used to investigate the effect of pore morphology of the moulds on the cake microstructures. A uniform microstructure of cast cake was formed for using an alumina mould and significant contamination was observed in using a plaster mould.