(Bi0.5Na0.5)ZrO3 modified KNN-based ceramics: Enhanced electrical properties and temperature insensitivity

Abstract To further improve the properties of KNN-based lead-free ceramics, a new ceramic system, (0.98-x)K0.525Na0.475Nb0.965Sb0.035O3-0.02 BaZr0.5Hf0.5O3-x(Bi0.5Na0.5)ZrO3(KNNS-BZH-xBNZ) was designed, the relevant properties such as piezoelectricity, strain, and temperature stability were analysed in detail. It was found that the R-T phase boundary can be successfully constructed when x=0.030, and this two-phase coexistence shows relatively good comprehensive properties (d33∼410 pC/N, TC∼255 °C, Suni∼0.132%, and d33*∼441 pm/V). Meanwhile, its strain property also shows good temperature stability from room temperature to 180 °C (Suni100°C/SuniRT∼97.5% and Suni180°C/SuniRT∼83.9%), which is comparatively superior to many KNN-based ceramics and some lead-based ceramics. Therefore, KNNS-BZH-xBNZ ceramics may broaden the practical application of lead-free ceramics.