EFFECT OF Al₂O₃-RO RATIO ON THE STRUCTURE AND PROPERTIES OF ALKALINE EARTH ALUMINOSILICATE GLASS BASED ON THE MOLECULAR DYNAMICS SIMULATION

Abstract

The molecular dynamics (MD) simulation method was used to study the influence of the Al 2 O 3 -RO (R = Ca, Mg) ratio on the structure and properties of CaO-MgO-Al 2 O 3 -SiO 2 -Na 2 O glass at high temperatures. The micro-structure characteristics, degree of network polymerisation (DNP), and high-temperature viscosity of the glass melts were analysed. The results showed that the coordination number of Si 4+ and Al 3+ remained about 4 in the process of replacing Al 2 O 3 with RO. The silicon-oxygen and aluminium-oxygen tetrahedron content showed a decreasing trend with a decrease in the Al 2 O 3 content, the bridging oxygen content decreased, and the degree of the network polymerisation of the glass decreased from 3.33 to 2.79. The decrease in the Al 2 O 3 content also caused a rapid decrease in the glass fibre-forming temperature from 1637.66 K to 1552.87 K. According to the molecular dynamics calculation, the linear relationship between the DNP and fibre-forming temperature was obtained.