Effects of BaSiO3 on the strain properties of Bi0.5Na0.5TiO3-based lead-free piezoelectric ceramics

To improve the strain properties of lead-free piezoelectric ceramics, the (0.82-x)Bi 0.5 Na 0.5 TiO 3 -0.18Bi0.5 K 0.5 TiO 3 -xBaSiO 3 piezoelectric ceramics with x=0-5% were investigated.The piezoelectric ceramic samples were fabricated using a conventional solid-state reaction method.The results of X-ray diffraction analysis and density measurements show a single perovskite structure as a pseudo-cubic phase with a relative density of over 95%.The dielectric properties of the studied samples strongly depend on the frequency, temperature, and BaSiO 3 content.The bipolar electric field-induced strain curves of the analysed samples show a phase transition from a ferroelectric phase to a relaxor phase when the BaSiO 3 content is over 3%.In particular, the maximum uni electric field-induced strain was found at the morphotropic phase boundary (MPB) composition.The x=0.03 sample shows a maximum strain of 0.167%, corresponding to the strain value under the electric field of 278 pm/V.The results suggest the potential of BaSiO 3 doping to enhance the strain properties of the lead-free Bi 0.5 Na 0.5 TiO 3 -based piezoelectric ceramics.