Formation of the structure and piezoelectric and dielectric properties of NaNbO3−KNbO3−CuNb2O6 solid solutions

Abstract

Ceramics of the 0.5NaNbO₃−(0.5–2x)KNbO₃−xCuNb₂O₆ system at x = 0−0.05 are produced via solid phase synthesis with subsequent sintering, according to the conventional technique. It is shown that introducing copper columbite into the (Na_1–y, K_y)NbO₃ binary system does not result in structural phase transitions; rather, it leads to the formation of K₂Nb₄O₁₁ impurity phase with the structure of tetragonal potassium tungsten bronze. A correlation between the dielectric properties of the investigated solid solutions and their quantity and the density of the samples is revealed.