Effect of sintering temperature on the structure and electrical properties of KNNS-0.03BNZ ceramics

(K0.48Na0.52)NbO3-0.03Bi0.5Na0.5ZrO3 (KNNS-0.03BNZ) ceramics were prepared doped with 3 mol% Bi0.5Na0.5ZrO3 (BNZ), and the effect of sintering temperature on dielectric and piezoelectric properties of KNNS-0.03BNZ was also investigated. KNNS-0.03BNZ ceramics at all sintering temperatures exhibit a single perovskite structure, and the change of sintering temperature has no significant effect on the phase composition of KNNS 0.03BNZ ceramics. The Raman shifts of the ν1 and ν5 vibration modes have irregular changes in all sintering temperature ranges, indicating that there are polycrystalline phases coexisting in this region. With the change of sintering temperature, Tc slightly shifts to the high temperature direction, and TR-T slightly shifts to the high temperature direction, dielectric constant εr continuously increases, while dielectric loss tanδ firstly decreasing and then increasing. Thanks to the presence of a small amount of liquid phase in the ceramics sintered at 1160 ℃, piezoelectric coefficient d33 reaches 280 pC/N.