Enhanced electric field-induced strain and electrostrictive response of lead-free BaTiO₃-modified Bi_0.5(Na_0.80K_0.20)_0.5TiO₃ piezoelectric ceramics

Lead-free (1-x)Bi0.5(Na0.80K0.20)0.5TiO3-xBaTiO3 or (1-x)BNKT-xBT (x = 0 – 0.15 mol fraction) piezoelectric ceramics have been investigated. The optimum density was found for the ceramic sintered at 1125°C, corresponding 98 99% of their theoretical values. All had a single perovskite structure. coexisting mixed tetragonal-rhombohedral phases all over entire compositional range with tetragonal phase becoming superior higher BT. diffuse transition promoted by addition With increasing BT content, Tm and Td values were to decrease. Phase from ferroelectric (FE) ergodic relaxor (ER) also induced changes in content. These significantly suspended long-range order, then correspondingly reducing Pr Ec, resulting an improvement electrostrictive electric field-induced strain responses. A significant response (Smax 0.37% d*33 630 pm/V) is noted x 0.05 ceramic. Furthermore, high coefficient (Q33) 0.0421 m4/C2 observed this composition, which more than ~ 2 times (~108%) as compared pure BNKT studied results indicated these can be considered promising candidates actuator applications.