Study of glass structures and crystalline phases in the PbO-Al2O3-SiO2 system†

Abstract

Glass structures in the PbO-Al2O3-SiO2 system, corresponding to stable chemical compounds in the respective phase equilibrium diagram, were investigated by high-temperature isothermal centrifugation (HTIC) and by X-ray diffraction, IR spectroscopy and other methods. A change in the structural micro-inhomogeneity of the initial glasses during HTIC was determined. This influences the change in the physical properties of these glasses and defines the character in the phase-formation during further thermal treatment. Methods for obtaining three different forms of crystalline lead metasilicate as well as a previously unknown lead aluminum-silicate are suggested. The intensities and positions of the X-ray indices of some basic lead aluminum-silicates were corrected.