The microwave dielectric properties of the (1 - x)Mg2(Ti 0.95Sn0.05)O4-x(Ca0.8Sr 0.2)TiO3 ceramic system prepared by mixed oxide route have been investigated. The crystal structures and the microstructures of the ceramics were characterized by means of X-ray and SEM. The microwave dielectric properties are strongly related to the density and matrix of the specimen. Combination of Mg2(Ti0.95Sn0.05)O4 (spinel-structured) and (Ca0.8Sr0.2)TiO3 (perovskite-structured) forms a two-phase system and leads to a near-zero τf. With increasing x, the microwave Q × f decreased and εr increased. A new microwave dielectric material 0.91Mg 2(Ti0.95Sn0.05)O4-0.09(Ca 0.8Sr0.2)TiO3, possessing excellent microwave dielectric properties with a dielectric constant (εr) of 18.32, a Q × f of 109,200 GHz (where f = 9.5 GHz, is the resonant frequency) and a τf value ∼-0.5 ppm/°C at 1270 °C for 4 h, is proposed as a suitable candidate material for microwave applications requiring low dielectric loss.
All Science Journal Classification (ASJC) codes
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry