Long-range granular feature of silicate glasses and its relation to glass properties

Abstract

Numerous experimental results show that silica and silicate glasses consist of higher density granules about 20 to 50 nm sized and lower density linkages. Such long-range feature should originate from the long-range density fluctuation of the glass-forming liquid. Due to the highly coordinated network structure of glass the lower density regions may be under strain. Following this assumption many phenomena of glass observed here and reported in the literature can be explained well, e.g. anomalous conductivity, brittleness, granular boundary contour of crack, high conductivity on the fracture surface, cloudy damage after dishwashing, corrosion products on glass surface, distribution pattern of Ag colloidal particles in float glass bath side, disproportional large influence of water on glass properties, the unusual increase in expansion coefficient with increasing modifier content, etc.