Phase Formation, Microstructure, and Dielectric Properties of

Phase Formation, Microstructure, and Dielectric
Properties of Bismuth Potassium Titanate Ceramic
Fabricated using the Combustion Technique
Atthakorn Thongtha, Artid Laowanidwatana and Theerachai Bongkarn*
Department of Physics, Faculty of Science, Naresuan University, Phitsanulok,
65000, Thailand
Research Center for Academic Excellence in Petroleum, Petrochemicals and
Advanced Materials, Naresuan University, Phitsanulok, 65000, THAILAND
The effect of sintering temperatures (975-1025 oC) on crystal structure,
microstructure and dielectric properties of perovskite bismuth potassium titanate
(BKT) ceramics was investigated. The pure BKT ceramics were firstly prepared using
the combustion technique. The phase purity, crystal structure and microstructure of
samples were examined using X-ray diffraction (XRD) and scanning electron
microscopy (SEM). The purity phase of the BKT samples, which has a tetragonal
structure, was observed in all samples. The lattice parameters a, c and the
tetragonality tended to decrease with increased sintering temperature. The SEM result
showed that the average grain size increased (0.37-0.58 m) with the increase of
sintering temperature (975-1025 oC). The shrinkage of the ceramics increased when
the sintering temperature increased. The maximum density and dielectric constant at
Curie temperature were around 5.71 g/cm3 and 3850, and were obtained from the
sample sintered at 1020 oC for 2 h. It is important to note that the preparation, using
the combustion technique, improve the density and dielectric properties of the BKT
*Presenting author’s email: [email protected]