Thermo-viscoelastic modeling of nonequilibrium material behavior of glass in nonisothermal glass molding
Abstract Nonisothermal Glass Molding (NGM) has become a viable replicative
manufacturing technology for the cost-efficient production of complex precision optical
components made of glass. During the pressing stage in NGM, glass materials undergo a
huge temperature change in the glass transition range. In this range, glass exhibits thermo-
viscoelastic responses, and the temperature drop through the glass transition leads glass
structure to depart from an equilibrium to a nonequilibrium state. Thermo-viscoelastic …
manufacturing technology for the cost-efficient production of complex precision optical
components made of glass. During the pressing stage in NGM, glass materials undergo a
huge temperature change in the glass transition range. In this range, glass exhibits thermo-
viscoelastic responses, and the temperature drop through the glass transition leads glass
structure to depart from an equilibrium to a nonequilibrium state. Thermo-viscoelastic …
Abstract
Nonisothermal Glass Molding (NGM) has become a viable replicative manufacturing technology for the cost-efficient production of complex precision optical components made of glass. During the pressing stage in NGM, glass materials undergo a huge temperature change in the glass transition range. In this range, glass exhibits thermo-viscoelastic responses, and the temperature drop through the glass transition leads glass structure to depart from an equilibrium to a nonequilibrium state. Thermo-viscoelastic properties of the nonequilibrium glass material greatly depend on temperature and thermal history. This paper presents a phenomenological constitutive model developed for modeling the thermo-viscoelastic responses of nonequilibrium glass. We propose a direct incorporation of the temperature -and thermal history effects into each parameter of the phenomenological model. This novelty allows the model to describe the nonequilibrium phenomena and to study temperature-dependent viscoelasticity of glass without assuming thermo-rheologically simple characteristics. Furthermore, the phenomenological model enables the coupling of structural -and stress relaxation phenomena. The model validation conducted for creep experiments demonstrates an enhancement in numerical predictions of the nonequilibrium material behaviors of glass over wide ranges of temperature and thermal history.
Elsevier
以上显示的是最相近的搜索结果。 查看全部搜索结果