Microwave dielectric properties of novel Mg3Ga2TiO8 ceramic

Mg3Ga2TiO8 ceramics were prepared using a solid-phase method. The ceramics sintered at 1440 degrees C exhibited excellent microwave dielectric properties (epsilon r = 12.07, Q x f = 89,270 GHz, and 'rf = -40.7 ppm/degrees C). The typical spinel structure of the Mg3Ga2TiO8 ceramic was confirmed through Rietveld refinement and Raman spectroscopy. High-resolution transmission electron microscopy indicated local lattice distortion in the Mg3Ga2TiO8 ceramics, with a Vickers hardness of 12.53 GPa. The values of epsilon r and Q x f for the Mg3Ga2TiO8 ceramics were affected by the relative density. The theoretical epsilon r obtained from the C-M equation was lower than the measured epsilon r, plausibly due to underestimation of the polarizability of the Ti ions. According to the P-V-L theory, Ti2-O1 has the highest fi value, contributing 29.92% to epsilon r. The contribution rate of the Ga2-O1 bond to U was 35.76%, with the greatest impact on Q x f.