Simulation of the Thermodynamic Properties of Glass-Forming Melts in the Na_2O-B_2O_3-SiO_2 System in the Framework of the Generalized Lattice Theory of Associated Solutions

摘要

The possibility of calculating the thermodynamic properties of melts in the Na_2O-B_2O_3-SiO_2 system(as in the previously studied Cs_2O-B_2O_3-SiO_2 system)formed by two glass-former oxides(B_2O_3,SiO_2)and one modifier oxide(Na_2O)with the use of the vacancy variant of the generalized lattice theory of associated solutions is demonstrated.A comparison with the experimental thermodynamic functions previously determined by the electromotive force method and high-temperature mass spectrometry at temperatures of 1200,1273,and 1350 K shows that the calculations performed within this approach lead to reliable thermodynamic functions.It is noted that the proposed model ignores the change in the coordination number of boron atoms to four and the possibility of forming associates in melts of compositions lying in the metastable phase separation region at temperatures higher than the phase separation temperature.