Formation and Microwave Dielectric Properties of the Mg2V2O7 Ceramics

The formation process and microwave dielectric properties of the Mg2V2O7 ceramics were investigated. The MgV2O6 phase that was formed at around 450 degrees C interacted with remnant MgO above 590 degrees C to form a homogeneous monoclinic Mg2V2O7 phase. Finally, this monoclinic Mg2V2O7 phase was changed to a triclinic Mg2V2O7 phase for the specimen fired at 800 degrees C. Sintering at 950 degrees C for more than 5 h produced high-density triclinic Mg2V2O7 ceramics. In particular, the Mg2V2O7 ceramics sintered at 950 degrees C for 10 h exhibited the good microwave dielectric properties of epsilon(r)=10.5, Q x f=58 275 GHz, and tau(f)=-26.9 ppm/degrees C.