Structure and microwave dielectric properties of the Li2O–MgO–TiO2 systems

In this paper, Li 2 O–MgO–TiO 2 (1: x :1, x  = 1, 2, 3, 4 and 5) ceramic systems were prepared by solid-state reaction sintering. The effects of extra magnesium content on the phase evolution, crystal structure and microwave dielectric characteristics of Li 2 O–MgO–TiO 2 ceramics were systematically investigated. The Li 2 MgTi 3 O 8 , Li 2 Mg 3 TiO 6 , and (Li 2 TiO 3 ) 10.667 coexisted at x  = 1 and 2. When x augmented to 3, the pure Li 2 Mg 3 TiO 6 -like phase was obtained with the increase of magnesium content. All specimens showed porous structure and clear grain boundaries. The microwave dielectric characteristics are extraordinary dependent on chemical component and densification. The Li 2 O–4MgO–TiO 2 ceramics sintered at 1350 °C possessed preeminent comprehensive performance of ε r  = 13.95, Q  ×  f  = 119,072 GHz and τ f   = − 40.9 ppm/°C.