Strontium barium niobate-relating structural developments and dielectric constant

Abstract

Strontium barium niobate (SBN) ceramics, synthesized through partial co-precipitation, was sintered at—6, 12 and 24 h, respectively, at 1250, 1300 and 1350 °C. Structural developments, developments in porosity, grain size, residual stress and crystallographic texture and its effect on dielectric constants were studied at different sintering conditions. The bulk crystallographic texture was largely unaffected by the sintering conditions used, though all other structural parameters evolved through sintering schedule. An effort was made to relate the changes in dielectric constant with the changes in structural parameters. Normal grain growth or changes in residual stress pattern either had relatively insignificant effects on dielectric constant or decoupling the relative effects was difficult from the present set of data. On the other hand, the strongest increase in dielectric constant was achieved through reduced porosity/defects, while abnormal growth caused the largest drop.