Abstract
The fabrication of 0.99[Bi0.5(Na0.82K0.18)0.5Ti0.995Nb0.005O3]-0.01LiSbO3 ceramics (BNKTNb-LSb) prepared by the combustion technique was studied. A single perovskite phase of BNKTNb-LSb powder was observed by the powders calcined at 700 °C for 2 h, which was lower than the solid-state reaction technique ∼150 °C. The BNKTNb-LSb ceramics showed the coexistence of a rhombohedral and tetragonal phase at a low sintering temperature. Then, the phase formation changed from a tetragonal to a pseudocubic phase when sintered at higher temperatures. The grain morphology of the BNKTNb-LSb ceramics exhibited a rather square shape and the average grain size of the ceramics was increased with increased sintering temperatures. The density, linear shrinkage, ϵr and ϵmax of the BNKTNb-LSb ceramics tended to increase with increasing sintering temperatures up to 1125 °C and then decreased. At 1125 °C, the highest density, shrinkage, ϵr and ϵmax were about 5.82 g/cm3, 18.7%, 1625 and 4465, respectively. The dielectric behavior corresponded with the XRD, density and the microstructure results.
Acknowledgements
The authors wish to thank the Department of Physics, Faculty of Science, Naresuan University, for supporting facilities. Thanks are also given to Dr Antony Harfield and Mr Don Hindle for their help in editing the manuscript.
Disclosure statement
No potential conflict of interest was reported by the authors.