Densification, Microstructure, and Electrical Properties of BaTiO3 (BT) Ceramics Prepared from Ultrasonically De-Agglomerated BT Powders

In this study, a correlation between densification, microstructure, and electrical properties of BaTiO3 (BT) ceramics prepared from ultrasonically de-agglomerated BT powders has been analyzed. BT powders with the same crystal structure (tetragonal) and stoichiometry, but with different average particle size, were used to prepare sintered ceramics. Densification and electrical properties of the sintered BT ceramics were correlated to the average particle size of the powders. It was found that a decrease in average particle size improved the densification process as well as the ceramics' microstructure. The impedance measurements were done up to 320°C in order to separate grain (bulk) and grain boundary contributions. Bulk resistance was more or less the same, independent on the average particle size of the powder. On the contrary, grain boundary resistance increased with decreasing average particle size of the powder