Effect of Grain Size of BaTiO_3 Ceramics on Dielectric Properties

摘要

BaTiO_3 ceramics with different grain size from 0.56 to 120 μm were prepared by the conventional solid state processing and two-stage sintering method using ultrafine BaTiO_3 powders prepared by a sol- gel method. Dielectric, ferroelectric and piezoelectric properties of BaTiO_3 ceramics with different grain size were investigated. The grain size effect of BaTiO_3 ceramics on dielectric appeared clearly. The coercive field showed a maximum value of 7.14 kV/cm at the grain size of 1.1 gm and piezoelectric constant d_(33) showed a maximum value of 204 pC/N at 8.9 μm. The remanent polarization of BaTiO_3 ceramics increased with the increasing of the grain size.