Multi-phase structure and electrical properties of Bi0.5Li0.5ZrO3 doping K0.48Na0.56NbO3 lead-free piezoelectric ceramics

Abstract

Abstract (1–x)K0.48Na0.56NbO3–xBi0.5Li0.5ZrO3 (KNN–xBLZ, x = 0–0.06) lead-free piezoelectric ceramics were prepared by the conventional solid-state sintering method, and their phase structures and electric properties as well as T C were systematically investigated. The orthorhombic–tetragonal (O–T) two phases were detected in all (1–x)K0.48Na0.56NbO3–xBi0.5Li0.5ZrO3 ceramics at 0.01 ≤ x ≤ 0.05. Due to the appropriate ratio between O phase and T phase (C O/C T= 45/55), high piezoelectric properties of d 33 = 239 pC/N, k p = 34%, and P r = 25.23 μC/cm2 were obtained at x = 0.04. Moreover, a high T C = 348°C was also achieved in KNN–xBLZ ceramic at x = 0.04. These results indicate that (1–x)K0.48Na0.56NbO3–xBi0.5Li0.5ZrO3 system is a promising candidate for high-temperature piezoelectric devices.

Keywords

• lead-free piezoelectric ceramics
• potassium–sodium niobate (KNN)
• solid-state sintering
• multi-phase
• electrical properties