Interactions between BaTiO3 and the B2O3-Bi2O3 system were studied by sintering BaTiO3 with B2O3/Bi2O3 glass powder. In general, the microstructural development of BaTiO3 depends very much on the amount and composition of glassy phase present in the samples during sintering. With large amounts of B2O3-Bi2O3 glassy phase and, as a consequence, a high Bi3+ donor-dopant concentration, the grain growth is suppressed. On the other hand, when the amount of donor-dopant supplied by the glassy phase decreases, the grain growth occurs, leading to the formation of semiconducting ceramics. All prepared samples exhibited the Positive Temperature Coefficient Resistivity (PTCR) effect.

Keywords: BaTiO3, semiconducting ceramics, PTCR effect, glassy phase, grain growth