Orthorhombic–tetragonal phase coexistence and piezoelectric behavior in (1−x)(Ba,Ca)(Ti,Sn)O3–x(Ba,Ca)(Ti,Zr)O3 lead-free ceramics

A new method has been used to prepare BaTiO3-based ceramics by combining Ba0.98Ca0.02Ti0.94Sn0.06O3 and Ba0.85Ca0.15Ti0.9Zr0.1O3, and (1−x)Ba0.98Ca0.02Ti0.94Sn0.06O3–xBa0.85Ca0.15Ti0.9Zr0.1O3 ceramics were prepared by the normal sintering. The effect of BCTZ content on their phase structure and piezoelectric properties is investigated. A dense microstructure is developed, and a coexistence of orthorhombic and tetragonal phases is identified in the ceramic with x = 0.40, showing a good dielectric and piezoelectric behavior of ɛr ∼ 5500, tan δ ∼ 0.3%, and d33 ∼ 407 pC/N. As a result, the combined method of BCTS and BCTZ could improve the piezoelectric properties of barium titanate ceramics.