Dielectric behaviors of Ba(Mg1/3Nb2/3)O3 modified (Na0.5K0.5)NbO3 ceramics

The effects of Ba(Mg1/3Nb2/3)O3 additives to lead-free (1-x)(Na0.5K0.5)NbO3-xBa(Mg1/3Nb2/3)O3 ceramics have been investigated. XRD patterns, SEM images and Raman spectra have been used to discuss phase structure transitions and microstructure. The dielectric behavior has been also investigated by using the empirical law, the Curie-Weiss law and the spin-glass model. Results show the diffused phase transition behavior to be enhanced by increasing Ba(Mg1/3Nb2/3)O3 addition and the dielectric behavior to be changed to the more short range order of relaxor ferroelectric. Barium and Magnesium cations are suggested to enter into the cation sites and induce the changes of lattice structure, microstructure, compositional fluctuation, cation disorder and correlation of neighboring cluster-sized moments.