Effect of Ta substitution on the dielectric and the piezoelectric properties of lead-free (Na0.53K0.47)0.96Li0.04(Nb1−x Ta x )O3 ceramics

Abstract

Ta-substituted (Na0.53K0.47)0.96Li0.04(Nb1−x Ta x )O3 ceramics (NKLNT, x = 0.0, 0.013, 0.015, 0.017, 0.019, 0.021) were prepared through the solid-state reaction method. The crystallized NKLNT single phases were confirmed by using X-ray diffraction. Ta-substitution affected the dielectric behaviors and the piezoelectric properties. The enhanced piezoelectric coefficient d 33 and planar electromechanical coupling coefficient k p were estimated to be 232 pC/N and 0.46, respectively. The effects of Ta substitution on the temperature dependences of the dielectric and the piezoelectric properties were investigated at temperatures around the orthorhombic-tetragonal phase-transition temperature (T O-T ).