Influence of BiNbO₄ Doping on Shift of Curie Point and Micro-properties of Barium titanate Ceramics

The influences of BiNbO₄ on the shift of Curie point as well as structural and micro-structural properties of BaTiO₃-based ceramics have been investigated.The experiment results showed that the tetragonality declined gradually with increasing BiNbO₄, while the Curie point initially reduced, minimized at 123℃, and then increased.The variation of Curie point agreed with the change of microstrain value.When the content of BiNbO₄ is in the range of 0~2 wt%, the grain growth was retarded, which was propitious to the densification of samples.However, excessive addition of BiNbO₄ would produce a secondary phase and increase the porosity.