STRUCTURE, GLASS STABILITY AND RHEOLOGICAL PROPERTIES OF Na₂O-CaO-Al₂O₃-SiO₂ GLASSES DOPED WITH Y₂O₃

Abstract

Abstract: The structure, glass stability and rheological properties of Na₂O-CaO-Al₂O₃-SiO₂ glasses with different Y₂O₃ content have been invesigated by DSC, FTIR, rotating crucible viscometer and dilatometry. The results showed that the addition of Y₂O₃ reduced the polymerization degree of glass network, but made the glass structure more compact. The coefficient of thermal expansion, density and glass transition temperature increased with the increase of Y₂O₃ content. The crystallization peak temperature and glass stability decreased firstly and then increased. While the melting temperature and forming temperature showed the opposite trend. The working temperature and Littleton softening point went up gradually. As the Y₂O₃ content changing from 0 to 2 mol%, the fragility index m decreased firstly and then increased, while the glasses working temperature range ΔT experienced an opposite change.

Keywords

• Structure
• Glass stability
• Rheological
• Fragility
• Viscosity