Crystalline structures, Raman, and Microwave dielectric properties of temperature stability Magnesium Niobate ceramics prepared by nanopowders

Magnesium Niobate (Mg 4 Nb 2 O 9 ) nanopowders were prepared as a precursor by the High Energy Ball Milling method to improve sintering stability of ceramics. CuO was used as addition to improve the sintering stability and microwave dielectric property of Mg 4 Nb 2 O 9 ceramics. X-ray diffraction and Raman analyses demonstrated that the solid solution between Mg 4 Nb 2 O 9 and CuO were formed because of their similar ionic sizes. The sintering ability and temperature stability of Mg 4 Nb 2 O 9 ceramics can be effectively improved by doping of CuO. At CuO content  x   = 3, Mg 4 Nb 2 O 9 ceramics exhibited an appropriate microwave dielectric properties with ɛ r  = 13.2, Q × f  = 27 800 GHz, τ f  = 4.2  ppm/ °C at 1150 °C.