Crystal structure and microwave dielectric properties of middle-temperature-sintered Mg2Si(1-x)V (x) O-4 ceramics

摘要

Mg2Si(1-x)V (x) O-4 (0.0 a parts per thousand currency sign x a parts per thousand currency sign 0.3) ceramics were fabricated via a conventional solid state reaction route, and their densification behaviors, structure and microwave dielectric properties were investigated systematically. A single phase Mg2SiO4 was obtained for the samples with x a parts per thousand currency sign 0.05, and the lattice constant increased with increasing V content due to the larger ionic radius of V5+ than that of Si4+. Moreover, the density and microwave dielectric property strongly depended on the substitution content of V5+ and sintering temperature. Typical, Mg2Si0.8V0.2O4 ceramic obtained a maximum density of 3.24 g/cm(3) and exhibited good microwave dielectric properties of epsilon (r) = 8.8, Q x f = 79900 GHz, and tau (f) = -57.5 ppm/A degrees C at 1180 A degrees C.