Аннотация:Influence of BiFeO3 (BF) on phase formation, unit cell parameters, microstructure, dielectric and ferroelectric properties of solid solutions close to the morphotropic phase boundary in the (Na0.50.5Bi0.5)0.5)TiO3–(K0.50.5Na0.5)0.5)NbO3 system additionally modified by the low-melting KCl additives has been studied. The formation of pure perovskite structure samples decrease in the unit cell parameters and increase in the TCTC value stimulated by the BF addition have been revealed. It was proved that modification of compositions by small amounts of the BF and KCl additives leads to improvement of dielectric parameters