Effect of glass composition on the dielectric properties of a liquid- phase-sintered MgO-doped BaTiO₃

A series of BaTiO₃-MgO-glass mixtures has been sintered via liquid-phase sintering in a reducing atmosphere at 12801C by controlling MgO/CaO ratio in an aluminum borosilicate glass composition, and the subsequent microstructure, phase evolution, and dielectric properties have been investigated. The growth of BaTiO3 grains was inhibited in all of the prepared specimens with the evidence of Mg incorporation to the BaTiO₃ lattice from the glass. The change in MgO/CaO ratio in the glass notably modified the dielectric properties: a high MgO/ CaO ratio in the glass resulted in a decreased dielectric constant, a decreased phase transition temperature, a broadened temperature range of phase transition, a decreased temperature coefficient of capacitance, and increased electrical resistivity.