Phase separation and properties of glasses of the system MgO–CaO–Fe ₂O₃–Al₂O₃–В₂O₃–SiO₂

Abstract

The synthesis and study of model glasses of the MgO–CaO–Fe2O3–Al2O3–SiO2 system, which is the base for obtaining continuous basalt fiber, has been carried out. Systematized data on the effect of components on the glasses structure and the sequence of phase separation processes occurring during their heat treatment have been obtained. It is shown that during phase separation, crystalline phases are separated in the following sequence: magnetite–pyroxene–plagioclase with a predominance of the anorthite component. Glasses of the MgO–CaO–Fe2O3–Al2O3–SiO2 system were modified by adding B2O3, and the active role of this component in the processes of glass formation and crystallization was shown. The ratio of glass-forming and modifying components of model glasses is established, at which an increase in the strength of glasses from 110 to 180 MPa is achieved. Based on the study of the technological properties of model glasses and strength characteristics, components were determined for modifying basalt glasses in order to increase the strength of the fiber.