Piezoelectric and ferroelectric properties of CN-doped K0.5Na0.5NbO3 lead-free ceramics

In this paper, lead-free (Na(0.5)K(0.)5)NbO3 ceramics doped with 1 mol % CuNb2O6 ceramics have been prepared by the conventional mixed oxide method with sintering temperature at 1075 degrees C. Microstructural analyses of NKN-xCN ceramics have been carried out and compared using x-ray diffraction and scanning electron microscope. The dependence of doping amount of the CN-doped NKN ceramics on the piezoelectric and ferroelectric properties has been investigated. The results show that the CN-doped NKN specimens sintered at 1075 degrees C present excellent "hard" piezoelectric properties of k(p)=40%, k(t)=45%, k(33)=57%, and ferroelectric properties E-c=25.5 kV/cm and P-r = 22.63 mu C/cm(2). The mechanical quality factor (Q(m)) of NKN ceramics with CN additive is extraordinarily high (1933). (C) 2010 American Institute of Physics. [doi: 10.1063/1.3493732]