Modeling thermophysical properties of glasses

Abstract

Metal oxide glasses are important in various industries because their properties can be tailored to meet application-specific requirements. However, there are few rigorous modeling tools for predicting thermomechanical properties of these materials with acceptable accuracy and speed, yet these properties can play a critical role in material design. In this article, a general multi-scale modeling framework based on Monte Carlo simulation and a cubic equation of state for predicting thermomechanical properties is presented. There are two novel and fundamental aspects of this work: (1) characterization of glass transition and softening temperatures as adjacent saddle points on the heat capacity versus temperature curve, and (2) a new moving boundary equation of state that accounts for structure and ‘soft’ repulsion. In addition, modeling capabilities are demonstrated by comparing thermomechanical properties of a pure B2O3 glass and PbO–B2O3 glass predicted by the equation of state to experimental data. Finally, this work provides a rigorous approach to estimating thermophysical properties for the purpose of guiding experimental work directed at tailoring thermomechanical properties of glasses to fit applications.