Effect of MnO content on the crystallization, physicochemical and dielectric properties of mica glass-ceramics

This paper has concentrated on the effect of partial substitution of MnO for MgO on the crystallization, physicochemical and dielectric properties of mica glass-ceramics. The results showed that MnO acted as a network modifier to diminish the network integrity. Fluorphlogopite (KMg 3 (Si 3 AlO 10 ) F 2 ) phase, as the dominant crystal phase, suggested that Mn 2+ ions did not participate in forming the mica phase. The crystallinity achieved the maximum (67.96%) at a MnO doping of 4 mol%. From SEM images, the conclusion that appropriate MnO doping could promote the formation of nuclei and refine the grains can be obtained. When the doping of MnO was 4 mol%, the Vickers hardness (4.59 GPa) of mica glass-ceramics was the lowest, while the bending strength (136.84 MPa) and chemical stability reached the best. The dielectric constant was about 7–8 at 1 MHz, and the dielectric loss remained relatively low.