Effect of yttrium oxide on the crystallization of glasses of the MgO-Al2O3-SiO2 system, nucleated by a mix of titanium and zirconium dioxides, and the transparency of glass-crystalline materials in the superhigh-frequency spectral region

摘要

Glass-crystalline materials of the MgO-Al2O3-SiO2 system are used for the production of items with low dielectric losses in the superhigh-frequency spectral region, high mechanical strength, and thermal stability of the dielectric properties. Some glass-crystalline materials of this system are also transparent in the visible region. This paper discusses the phase transformations that accompany the crystallization of glasses of the MgO-Al2O3-SiO2 system with an additive of yttrium oxide, nucleated by a mix of titanium and zirconium dioxides. Segregation of nanosize crystalline phases not previously recorded in this system is detected. A mechanism is proposed for the effect of yttrium oxide on the phase-separation processes. The permittivity and the tangent of the dielectric-loss angle at a frequency of 10(10) Hz of the glass-crystalline materials with a mixed crystallization nucleator are compared with the phase composition of the samples. (C) 2015 Optical Society of America.