The effect of a barium titanate xerogel precursor on the grain size and densification of fine-grained BaTiO3 ceramics

Abstract

In this study, we mixed a xerogel precursor of BaTiO3 (X-BTO) prepared by the sol-gel method into identical BaTiO3 powders obtained by co-precipitation during granulation to obtain fine-grained and dense BaTiO3 ceramics at a low sintering temperature (Ts). The effects of X-BTO, Ts, and dwelling time on the grain size and density of the BaTiO3 ceramics showed clear trends, and have predictable effects on the dielectric properties. With increasing X-BTO content, samples underwent a transition from the cubic phase to the tetragonal phase, the mean grain size increased, and the density and maximum dielectric constant first increased and then slightly decreased. Based on the requirements for dense and fine-grained ceramics with particle sizes comparable to powders, the BaTiO3 ceramic with 8 wt% X-BTO sintered at 940 °C exhibited improved permittivity (2445) and acceptable dielectric loss (0.019). This approach makes it possible to control the ceramic grain size by changing the powder's particle size, thereby creating fine-grained and dense BaTiO3 ceramics at a lower Ts.