The Effect of Firing Temperatures on Phase Evolution, Microstructure, and Electrical Properties of Ba(Zr0.05Ti0.95)O3 Ceramics Prepared via Combustion Technique

Abstract

In this work, the effects of calcination temperature (900 ºC – 1200 ºC for 2 h – 6 h) and sintering temperature (1350 ºC – 1550 ºC for 2 h) on phase evolution, microstructure and electrical properties of barium zirconate titanate Ba(Zr0.05Ti0.95)O3 (BZT) ceramics fabricated through the combustion technique were investigated. Glycine was used as fuel to reduce the reaction temperature. It was found that a single perovskite phase of BZT powders was observed from the sample calcined at 925 ºC for 6 h, which was lower than the solid state reaction technique ~275 ºC. The purity phase of an orthorhombic structure was observed in all ceramic samples. The average particle size (190 nm – 420 nm) and the average grain size (2.9 mm – 41.4 mm) increased with increased firing temperatures. The maximum theoretical density of ~96.8 % was obtained from the sample sintered at 1450 ºC for 2 h. The dielectric constant at room temperature (Tr) and the dielectric constant at Curie temperature (Tc) increased with increased sintering temperatures up to 1450 ºC and decreased thereafter. The dielectric properties corresponded to the obtained densities. The remnant polarization (Pr) of the BZT ceramic (using the coercive electric field of 20 kV/cm) increased with increasing sintering temperature. DOI: http://dx.doi.org/10.5755/j01.ms.20.4.6436

Keywords

• barium zirconate titanate
• combustion technique
• phase evolution
• perovskite structure