THE STRUCTURAL PHASE AND MICROSTRUCTURES OF PEROVSKITE Ba(Ti1-xZrx)O3 CERAMICS USING THE COMBUSTION ROUTE
Ba ( Ti 1-x Zr x) O 3; BTZ (x = 0.20 and 0.25) ceramics are attractive candidates for dynamic random access memories, tunable microwave devices and capacitors. In this study, the preparation of BTZ powders and ceramics fabricated by the combustion method were studied in detail. The calcination and sintering conditions were performed from 600 to 900°C for 4 h and from 1300 to 1450°C for 2 h, respectively. The highest percentage of the cubic perovskite phase was found in the powders that were calcined at 800°C. A pure cubic perovskite structure was found in all ceramic samples. The average grain size increased with increasing sintering temperatures. Dielectric constant-temperature plots showed a maximum peak value of 7500 and 8300 for x = 0.20 and 0.25. The phase transition temperature of the BTZ ceramics occurred at 30°C and 10°C for x = 20 and 25, respectively.