Effect of Particle Size of BaCO3 and TiO2 powders on the Properties of BaTiO3 Ceramics

BaTiO₃ as the classical ferroelectrics has been found extensive applications in electronic devices over the past decades. How to obtain fine BaTiO₃ particles with considerable high tetragonality which shows direct influence on the macroscopic properties of the sintered ceramics is a hot issue for fabrication throughout. In this paper, we studied the effect of the coordination ratio of the particle size of the BaCO₃ and TiO₂ powders (abbreviated as Sb/St) in the solid-state reaction. We found that by increasing the S_B/S_T from 0.43 to 1.8, the tetragonality of the obtained BaTiO₃ powders enhanced from 1.0065 to 1.0105. Moreover, when S_B/S_T<;1, agglomeration occurred and resulted in coarse particles. The maximum of the dielectric constant at Curie temperature increased from 6000 to 10000. Besides, the remnant polarization P_r changed from 1.12 μC/cm² to 6.07 μC/cm² and E_C changed from 84 kV/mm to 179 kV/mm. Such enhancements in both dielectric and ferroelectric properties could be ascribed to the increasement of the c/a ratio.