The microstructure and properties of Ag(Nb_0.8Ta_0.2)_1−x(Mn_0.5W_0.5) _xO₃ ceramic system

Abstract

The microstructure and dielectric properties of Ag(Nb_0.8Ta_0.2)_1−x(Mn_0.5W_0.5) _xO₃ (x=0, 0.04, 0.08, 0.12, 0.16) ceramic system were investigated. The Ag(Nb_0.8Ta_0.2)_1−x(Mn_0.5W_0.5) _xO₃ ceramics were prepared by the traditional solid-state reaction method and were characterized by X-ray diffraction (XRD), scanning electron microscopy(SEM) and Raman spectrometer. The sintering ability and dielectric properties of Ag(Nb_0.8Ta_0.2)_1−x (Mn_0.5W_0.5) _xO₃ were found to be improved with the doping of Mn⁴⁺ and W⁶⁺ ions. The densification temperature of Ag(Nb_0.8Ta_0.2)_1−x(Mn_0.5W_0.5) _xO₃ ceramics decreased from 1 080 °C to 1 000 °C when x increased from 0 to 0.16. Ag(Nb_0.8Ta_0.2)_1−x(Mn_0.5W_0.5) _xO₃ ceramic was found to have the best dielectric properties when x=0.08, larger permittivity (ɛ=547) and smaller dielectric loss (tanδ=0.00156).

Keywords

dielectric properties / silver niobate tantalite / MnO₂ / WO₃

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