EFFECT OF THE CaO-MgO-Al₂O₃-SiO₂ GLASS COMPOSITION ON THE MICROSTRUCTURE AND RHEOLOGICAL PROPERTIES FROM A MOLECULAR DYNAMICS SIMULATION

By adjusting the ratio of SiO 2 /RO (R=Ca, Mg), this article studied the atomic structure of CaO-MgO-Al 2 O 3 -SiO 2 glassy melts by a molecular dynamics simulation. The Pair distribution function (PDF), Coordination number (CN), bridging oxygen (BO), non-bridging oxygen (NBO), and Qn were utilised to characterise the glass structure. The results indicated that the content of the bridging oxygen was decreased with the RO replacing the SiO 2 . The total content of Q4 in the tetrahedron changed significantly from 34.11 % to 18.06 %. Meanwhile, the NBO/T parameter increased from 1.298 to 1.555. In the corresponding viscosity test, the melting temperature, fitted by the MYEGA equation, also decreased with the decrease in the SiO 2 content, and the fragility value increased from 39.12 to 53.20. Finally, the fragility and NBO/T were linked to describing the relationship between the mid-range structure and the rheological property. Moreover, the analyses showed that they had a linear relationship.