LAUSR

Abstract The Na 0.5 K 0.5 NbO 3 (NKN) ceramics with K/Na excess dopants were prepared by employing the two-step sintering process. The K/Na excessed NKN ceramics were researched by varying the sintering temperature, in order to optimize their piezoelectric properties by employing a conventional sintering method. Also, the effects of dwell time for the two-step sintering process on the ceramic properties were studied. The crystalline structure of the NKN ceramics with K/Na excess dopants were measured by X-ray diffraction (XRD) analysis. The microstructure was examined by field emission scanning electron microscopy (FE-SEM). In addition, piezoelectric coefficient, d 33 and relative dielectric permittivity ɛ r , will be discussed. In this research, we expected to improve the piezoelectric and dielectric properties of NKN lead-free piezoelectric ceramics by employing excess dopants of K/Na and the two-step sintering process.