A dense microstructure was developed for the 0.95(Na0.5K0.5)NbO3-0.05BaTiO3 (0.95NKN-0.05BT) ceramics sintered at above 1050 °C. Grain growth was observed in the specimens sintered at 1050-1060 °C while a liquid phase was found in the specimens sintered at above 1050 °C, which explained the increased sinterability and grain size. KTiNbO5 and Ba6Ti2Nb8O30 second phases were also observed for the specimens sintered at above 1060 °C. Evaporation of Na2O was responsible for the formation of the liquid phase and the KTiNbO5 and Ba6Ti2Nb8O30 second phases. Muffling with 0.95NKN-0.05BT powders during the sintering improved the piezoelectric properties, possibly due to the increased poling efficiency resulting from the reduced Na2O evaporation.
- Alkaline niobate
- Barium titanate
- Lead-free piezoelectric ceramics
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Mechanical Engineering