Effect of Li2Si2O5 Addition on the Sintering and Microstructure of BaTiO3

Densification behavior and micro structural characteristics were examined for BaTiO3 containing 0.25-2.00mass% Li2Si2O5. Li2Si2O5 lowered the sintering temperature of BaTiO3. The optimum concentration to obtain high density was 1mass%. A concentration smaller than the optimum value did not effectively lower the sintering temperature, while a larger concentration resulted in the formation of inhomogeneous microstructure. There was an optimum sintering temperature to obtain compacts with maximum density. Extensive grain growth occurred above the optimum temperature. The grain boundary phase, which was a liquid phase at the sintering temperature, contained TiO2-rich particles, whose distribution was non-uniform. The formation mechanisms of such microstructure were discussed.