Synthesis and Microwave Dielectric Properties of Mg_5Nb_4TiO_(17) Ceramics

摘要

Mg_5Nb_4TiO_(17) ceramic was prepared by the conventional solid-state route for the first time and its microwave dielectric properties were investigated. The crystal structure and microstructure were analyzed using X-ray diffraction and scanning electron microscopy techniques. With increasing sintering temperature, the dielectric constant (ε_r) and quality factor (Q×f) increased firstly and then decreased, while the τ_f nearly unchanged. Mg_5(NbTi)_4O_(15)-MgNb_2O_6 composite ceramics sintered at 1200 °C exhibits microwave dielectric properties of ε_r=15.1, Q×f=34,266.6 GHz (at 8.5GHz), τ_f=-63.8 ppm/oC.