Enhanced ferroelectric properties in (Ba_(1-x)Ca_x)(Ti_(0.94)Sn_(0.06))O_3 lead-free ceramics

摘要

Lead-free (Ba_(1-x)Ca_x)(Ti_(0.94)Sn_(0.06))O_3 (BCST) (x = 0.01-0.04) ceramics were prepared using a solid-state reaction technique. The effects of Ca content on the phase structure and electrical properties of the BCST ceramics were investigated. High piezoelectric coefficient of d_(33) = 440 pC/N, planar electromechanical coupling factor of k_p = 45% and dielectric constant ε_r = 6900 were obtained for the samples at x = 0.03. At room temperature, a polymorphic phase transition (PPT) from orthorhombic phase to tetragonal phase was identified in the composition range of 0.02