Large Strain Response and Fatigue-Resistant Behavior in Ternary Bi0.5Na0.5TiO3-BaTiO3-Bi(Zn0.5Ti0.5)O3 Solid Solutions

A ternary solid solution (1-x)(0.88Bi(0.5)Na(0.5)TiO(3)-0.12BaTiO(3))-xBi(Zn0.5Ti0.5)O-3 (BNBZT, BNBZTx) was designed and fabricated using the traditional solid-state reaction method. The temperature and composition dependence of dielectric, ferroelectric, piezoelectric, and fatigue properties were systematically investigated and a schematic phase diagram was proposed. The substitution with Bi(Zn0.5Ti0.5)O-3 was found to shift the phase transition (ferroelectric tetragonal to relaxor pseudocubic phase) to lower temperatures. At a critical composition x of 0.05, large electric-field-induced strain response with normalized strain S-max/E-max as high as 526pm/V was obtained under a moderate field of 4kV/mm around room temperature. The strain exhibited good temperature stability within the temperature range of 25 degrees C-120 degrees C. In addition, excellent fatigue-resistant behavior was observed in the proposed BNBZT solid solution after 10(6) bipolar cycles. These give the BNBZT system great potential as environmental friendly solid-state actuator.