Dielectric Properties of the Lead-Free Compositions Based on Sodium–Bismuth Titanate and Alkali Metal Niobates

The use of mechanical activation in the production of (1 – x)(Na_0.5K_0.5)NbO₃–x(Na_0.5Bi_0.5)TiO₃ ceramics is shown to increase the relative density of the ceramics by more than 10%. Several morphotropic phase transitions are found to appear in the system (1 – x)Na_0.5K_0.5NbO₃—xBi_0.5Na_0.5TiO₃ at room temperature. An increase in the amount of Bi_0.5Na_0.5TiO₃ in the system under study is shown to increase the temperature stability of the dielectric properties in the range 100–250°C. Solid solutions in the system (1 – x)Na_0.5K_0.5NbO₃–xBi_0.5Na_0.5TiO₃ with a high Bi_0.5Na_0.5TiO₃ content are promising bases for charge storage devices.