Phase structure and electrical properties of (1 − x)K0.48Na0.52NbO3–xBi0.46La0.04(Na0.82K0.18)0.5ZrO3 lead-free piezoceramics

Abstract

In this work, (1 − x)K0.48Na0.52NbO3–xBi0.46La0.04(Na0.82K0.18)0.5ZrO3 (abbreviated as KNN–xBLNKZ) lead-free piezoelectric ceramics were fabricated by using the conventional solid-state method. The phase structure, microstructure, and electrical properties of KNN–xBLNKZ ceramics have been investigated. Both large piezoelectric coefficient (d33 ~368 pC/N) and high Curie temperature (TC ~323 °C) can be achieved for the composition of x = 0.050 with rhombohedral–orthorhombic–tetragonal (R–O–T) multi ferroelectric phases coexistence near room temperature. In addition, a good thermal stability of piezoelectricity can also be observed in this composition (e.g., d33 ≥ 308 pC/N, Ta ≤ 300 °C). Therefore, we believe that this material system is a promising lead-free piezoelectric candidate for the high-temperature piezoelectric applications.