Influence of TiO2 additive on sintering temperature and microwave dielectric properties of Mg0.90Ni0.1SiO3 ceramics

(1-x)Mg0.90Ni0.1SiO3-xTiO2 (x = 0, 0.01, 0.03, 0.05) ceramics were successfully formed by the conventional solid-state methods and characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS), and their microstructure and microwave dielectric properties systematically investigated. It was observed that when TiO2 content increased from 0 to 5 wt%, the Qufo of the sample decreased from 118,702 GHz to 101,307 GHz and increases the τf value from −10 ppm/°C to +3.14 ppm/°C accompanied by a notable lowering in the sintering temperature (125 °C). A good combination of microwave dielectric properties (εr ∼ 8.29, Qufo ∼ 101,307 GHz and τf ∼ −2.98 ppm/°C) were achieved for Mg0.90Ni0.1SiO3 containing 3 wt% of TiO2 sintered at 1300 °C for 9 h which make this material of possible interest for millimeter wave applications.