Processing by both classical and mechanosynthesis routes and characterization of a new solid solution of tungsten–bronze structure ceramics

A new family of ferroelectric compounds with Ba 2− x Na 1+ x Li x Nb 5O 15 composition (0 ≤ x ≤ 1) and tetragonal tungsten–bronze structure is processed for the first time. This new family of materials derived from Ba 2NaNb 5O 15 compound was processed by classical solid-state reaction and by mechanosynthesis. The powders prepared by these two routes were characterized by X-ray diffraction (at room and high temperature), differential thermal analysis, thermogravimetry and scanning electron microscopy. The results confirm the formation of the solid solution in the whole range of composition. The influence of Li addition on the dielectric permittivity and losses and on the ferro-paraelectric transition temperature is also studied.