Dielectric and piezoelectric properties of (1 − x)(K0.498Na0.498Li0.04)NbO3–x(Bi0.5Na0.5)0.9Ba0.1(Zr0.0055Ti0.9945)O3 lead-free ceramics

(1 − x )(K 0.498 Na 0.498 Li 0.04 )NbO 3 – x (Bi 0.5 Na 0.5 ) 0.9 Ba 0.1 (Zr 0.0055 Ti 0.9945 )O 3 (KNLN–BNBZT100 x , x = 0, 0.01, 0.02, 0.03, 0.05, 0.1) lead-free ceramics were prepared by conventional solid-state reaction technique. The influences of the BNBZT on the crystal structure, dielectric, and piezoelectric properties of the ceramics were investigated. The ceramics formed single-phase solid solutions with perovskite structure after sintering in air at 1050–1100 °C for 3–4 h. Morphotropic phase boundary (MPB) between orthorhombic and tetragonal phase was found in the composition range of 0.01 ≤ x ≤ 0.02. The Curie temperature, T c , and the orthorhombic–tetragonal transition temperature, T O–T , shifted to low temperature as BNBZT increased. The dielectric and piezoelectric properties of ceramics were enhanced for the composition near the MPB. The maximum value, 194 pC/N, of piezoelectric constant d 33 together with the mechanical quality factor Q m , 20, were obtained when BNBZT content was 2 mol%.