Relaxor properties of 0.65 K0.5Bi0.5TiO3–0.35 BaTiO3 ceramics

Influence of K 0.5 Bi 0.5 TiO 3 on the structure, dielectric and ferroelectric properties of (Ba,Ca)(Zr,Ti)O 3 ceramics

“…Further increase of the KBT content to 65% in both BCZT compositions caused the appearance of another second phase, BaBi4Ti4O15, which was evident as blocky white crystals in the microstructure. It was suggested by Yang that the appearance of this phase could be due to the reaction of residual Bi2O3, TiO2, and BaCO3 [24], which might be associated with the use of a relatively short time of mixing the BCZT and KBT powders (4 hours in the present case). The chemical compositions of the BCZT matrix and secondary phases were confirmed by EDX, as shown in Figure S1.…”

“…The results showed that the presence of 0.1 mol% Bi2O3 can allow the sintering temperature to be reduced from 1500ºC to 1350ºC. Regarding the use of perovskite compounds for this purpose, it was reported that the sintering temperature of BT ceramics modified with KBT can be decreased to 1280ºC for 10 mol% KBT [20] and to 1125ºC for 65 mol% KBT [24]. In another study, it was found the use of 4 mol% KBT enabled the sintering temperature of (Ba0.85Ca0.15)(Ti0.93Zr0.07)O3 to be reduced from 1500ºC to 1280ºC [19].…”

“…This type of chemical heterogeneity may be related at least partially to 20 the processing procedures, which involved separate calcination of the BCZT and KBT powders prior to mixing and sintering. The presence of the K4Ti3O8 second phase was clearly apparent as darker regions (in BSE imaging mode) and is attributed to the evaporation of bismuth during the sintering process [24,32,33].…”