Dielectric behavior and microstructure of (Bi1∕2Na1∕2)TiO3–(Bi1∕2K1∕2)TiO3–BaTiO3 lead-free piezoelectric ceramics

Abstract

( 0.95 − x ) ( Bi 1 ∕ 2 Na 1 ∕ 2 ) TiO 3 – x ( Bi 1 ∕ 2 K 1 ∕ 2 ) TiO 3 – 0.05 BaTiO 3 lead-free piezoelectric ceramics (abbreviated as BNT–BKT–BT100x with x varying from 0 to 20 mol %) are prepared by a solid-state reaction process. Variation of the dielectric properties and microstructure of BNT–BKT–BT100x ceramics with BKT content is studied. The results indicate that the relative permittivity εr and loss tangent tanδ vary with the BKT amount. Scanning electron microscope observation also indicates that BKT in high amount affects the microstructure. X-ray diffraction analysis shows that the incorporated BKT diffuses into the BNT–BT lattice to form a solid solution during sintering.