Numerical Simulation of a Viscoelastic Thinning Process for Preparing Flexible Glasses by Redrawing Method

Abstract

The forming process of the flexible ultrathin glasses (UTG) prepared by the redrawing method was numerically simulated using ANSYS Polyflow software. In the forming process by the redrawing method, temperature, viscosity, transverse and longitudinal velocity distribution of the glasses with different compositions were studied. Furthermore, the influence of these factors on the width and thickness of the flexible glass plate was investigated. It is found that the internal and external heat exchange of glass has a dominant influence on the viscosity variation during the UTG forming process, which is inconsistent with the general viscosity-temperature dependence. The glass that first reaches the lower limit of forming viscosity can significantly resist the shrinking effect caused by surface tension, making the glass wider during the forming. If the original glass width remains unchanged, the glass thickness or feeding speed is reduced, wider and thinner flexible glasses can be produced.

Keywords

flexible ultra-thin glass (UTG) / numerical simulation / down-draw forming / redrawing method

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