화학공학소재연구정보센터
Journal of Materials Science, Vol.50, No.18, 6171-6179, 2015
Phase transitions, ferroelectric, and piezoelectric properties of lead-free piezoelectric xBaZrO(3)-(0.25-x)CaTiO3-0.75BaTiO(3) ceramics
Lead-free xBaZrO(3)-(0.25-x)CaTiO3-0.75BaTiO(3); x = 0.00-0.25 ceramics were successfully prepared using the conventional solid-state reaction method. Analysis of the sintered ceramics showed that all compositions exhibited a pure phase perovskite. The effects of composition on the phase transition, ferroelectric properties, and piezoelectric properties were studied. With the increasing BaZrO3 content, the phase transition temperature (T (C)) decreased and the coercive field E (c) decreased. The phase diagram featuring a cubic-rhombohedral-tetragonal triple point (x similar to 0.125) was derived from X-ray diffraction data and dielectric data as a function of temperature. Compositions near the convergence region exhibited the maximum peak in permittivity of similar to 11,400 at T (C). In addition, the morphotropic phase boundary compositions showed an enhancement in ferroelectric and piezoelectric properties. The composition 0.125BaZrO(3)-0.125CaTiO(3)-0.75BaTiO(3) exhibited the highest strain values of 0.14 % and a d (33) (*) of 474 pm/V.