Effect of the synthesis route on the phase formation and dielectric property in Ba,(Zr,Ti)O3-(Ba,Ca)TiO3 ceramics

Resumo

Ceramics of (1−x)Ba(Zr_0.2Ti_0.8)O₃–x(Ba_0.7Ca_0.3)TiO₃ (BZT-BCT) are one of the promising candidates to substitute the lead zirconate titanate (PZT) ceramics. Some authors have named these compositions as Ba_1-xCa_xTi_1-yZr_yO₃ (BCZT) while others as BZT-BCT. That way, this terminology can lead the interpretation that ceramics of BCZT were prepared from precursor powders ``direct route” (carbonates, oxides, etc), while ceramics of BZT-BCT are synthesized by the mixture of BZT and BCT solid solutions in a “composite route.” Therefore, this paper aims to put light into the influence of the processing route on the properties of these compositions. The method used was the preparation of the ceramics by two routes: BCZT, named as a monophasic system, prepared by the direct route and BZT-BCT, designed polyphasic system, prepared by a composite route. The results show that the processing influences the structure, microstructure, dielectric properties, and phase transitions of the ceramics. These findings are particularly relevant for the discussion of the phase development and compositional complexity of these materials.