High piezoelectric properties of batio3 ceramics prepared by two-step sintering technique through conventional solid-state reaction route

A two-step sintering technique was attempted to acquire BaTO₃ ceramics with dense and small-grained microstructure through conventional solid-state reaction route, in which BaCO₃ and TiO₂ powders are adopted as the starting raw materials. It has been found that the two-step sintering technique is effective even for the synthesized BaTiO₃ powder of submicron-sized particles. A BaTiO₃ ceramic with relative density as high as 98.2% and small grain size of about 1.7 μm was successfully obtained. Its dielectric and piezoelectric properties were investigated and compared with those of the ordinarily-sintered BaTiO₃ ceramic under an optimized sintering condition. The ceramic prepared by the new technique shows high piezoelectric properties of d₃₃ = 390 pC/N and k_p = 0.40 and is thus much superior to the ordinarily-sintered one, which displays only d₃₃ = 300 pC/N and k_p = 0.32. The results demonstrate that fabricating BaTiO₃ ceramics with ideal microstructure and high piezoelectric properties at low cost is possible.